Grapes are an economically important commodity, supplying fresh, dried, and processed markets worldwide. Although grapes are not a crop you immediately consider a beneficiary of CEA technology, it may be possible to adapt field agriculture, putting in measures to circumvent climate change and disease. 

The last few years I’ve been attempting to grow my own grapevine indoors, so when Chris Higgins shared the main photo I felt excited to learn how they were using LED lights to help fruit mature on vines in California. 

Could CEA also work for my grapevines?

Scotland is not known for wine but with changing climates and carefully chosen hardy varieties it could provide some competition for our national drink. Success at home is just around the corner as I begin season three with my black Hamburg grape (Schiava Grossa) grafted on S04 rootstock. It’s hopeful too, as earlier than expected it is producing trusses. The learning curve is not as steep as you may think and the trick is to not give up with a fruitless vine. 

We will take a look at the growing environment, the diseases that can be encountered and the pests that need to be eliminated by controlling some of the processes. Then we will examine some real Californian vineyards and how they are adapting and integrating CEA technology to increase efficiency and yield, battling against ever changing climates and earlier than predicted seasonal frosts. 

Year 3 indoors black Hamburg (dessert grape)  in central Scotland

Wine has an important role in world trade

Grapes were one of the earliest fruits cultivated for use as a beverage, and statues in ancient Roman culture were often adorned with grapes and wine decanters. In fact, many of the production principles first developed in ancient Rome can be found in winemaking today. Wine is classed as a cultured beverage and body, flavor, aroma, keynotes and vintage all play a part in how we decide to consume it. Aside from commercial vineyards, many vines can be cultivated under glass. This can be a lean-to, a conservatory, a polytunnel or a glasshouse, it doesn’t really matter. Mine are grown in a conservatory with great levels of natural light and temperatures rising to 105°F which helps ripen the fruit. 

The global wine market was valued at USD 417.85 billion in 2020 and growth is expected to expand to 6.4% CAGR by 2028. According to a recent report Italy, France, and Spain were the top three producers of wine worldwide as of 2022. In the Americas, Chile has the leading share of exports, almost three times more than the USA and Canada. Changing consumer preferences are evident with demand for fresh fruit, looking for year-round availability and consumers more willing to pay more for imported out-of-season fresh grapes.

Growing and Grafting Vines

Choosing the right rootstock is vital to ensure a successful harvest since the parent vine, Vitis. vinifera does not provide adequate resistance against phylloxera Vastatrix, a deadly root infection caused by the aphid-like insect, Daktulosphaira vitifoliae (Fitch). Phylloxera weakens the vines causing root galls making it susceptible to fungal infections. It has plagued vineyards, decimating crops in California, and completely devastated vines planted on AXR1 type B rootstocks. It is estimated to have cost the industry $6 billion to uproot valuable mature vines and replant with vines grafted onto sturdier rootstocks. 

To overcome this disease, grapes are grown on rootstocks from a variety of Vitis species selected from native areas or hybrids that use native species to form new rootstocks. The most commonly used are Vitis rupestris, V. riparia, V. berlandieri, and V. champinii. A grafted vine consists of the scion which is seen above ground and the rootstock which provides the root system and lower trunk joined at the graft union (protected with wax like above). 

Image by Wine Folly

Pruning is an artform and traditional viticulture techniques require patience and skill passed down through generations. Below are a few training techniques used in viticulture but you can learn more by following Dan from apicaltexas with great videos on pruning techniques in the field. 

Developing the vineyard should factor the best rootstock suited for particular environmental conditions. Soil type, pest resistance, tolerance to drought, wetness, salinity, and lime must all be considered when siting a vineyard.

Most experts suggest loamy soil as the best type of soil for grape growing. A crumbly mix of sand, silt, and clay when blended with other soils in the right amounts offers the ideal soil type. This is because the clay in loam drains well but also contains moderate amounts of water and nutrients within the preferred pH range (pH 6.5-6.8). Sonoma and Napa Valley are both loam soil regions. 

Even though grapevines are considered relatively tolerant to water deficits, growth and yield can be reduced in drought-like conditions. Drought tolerant rootstocks enable the scion to grow and yield even when water supplies are limited, a desirable trait if irrigation is likely to cause waterlogging in heavy clay soil. Acidic soils are common in many viticultural growing regions, and liming is common-practice to increase soil pH. The salinity of irrigation water and rising water tables can also affect productivity in grapevines which can have a  detrimental effect on wine quality.

Rootstocks can have a pronounced influence on the mineral nutrition of the fruiting variety. Vigorous vines can deplete zinc levels while increasing the uptake of potassium with regular soil analysis crucial to produce the best fruit. 

While growing under cover may not suit large scale vineyards, certainly the early stages can be started off under greenhouse control much like blueberries. A drip irrigation system will work well to ensure a good source of minerals is available at the root base with free drainage. 

If you are planning to grow in containers, a half barrel size is more than adequate with a light multipurpose compost. There’s no doubt selection of soil can be tricky because the soil type needs to work for both the vine and the rootstock. Remember sandy soil seems to have an advantage in resistance to phylloxera.

Microclimates & Disease Prevention 

Year one begins with training the cordon or guyot from the rootstock to produce two dominant shoots. Year two and the tendrils will form without fruiting but it is not until year three that fruit trusses will become visible on most vines. These can then be trained as desired with supports. How vigorous the growth develops will hugely depend on whether it’s grown as scions or as dominant root stocks. 

Mildew, powdery (Erisyphe necator) and downy (Plasmopara viticola) mildew are the predominant diseases encountered in viticulture. These favor successive periods of hot and humid conditions. Suppression of grapevine powdery mildew is problematic with resistance built up to systemic fungicides. This can also lead to weakened vines and susceptibility to Botrytis (botrytis cinerea) another fungal disease which affects almost every part of the vine, usually caused by high humidity coupled with strong winds. Mitigation traditionally introduces better airflow through the truss and canopy, pinching out individual berries can assist, allowing for circulation to circumvent rot problems. New ideas using light treatments are being trialed at Cornell university and UV treatments applied once a week up to 200 J/m2 on Chardonnay vines have proven to reduce powdery and downy mildew conidia germination by almost 100% and 50% respectively. 

Image sourced from David M. Gadoury, Cornell.

LEDs have also been shown to boost yields. RB light encourages leaf growth and fruit maturation but little experimentation has been possible due to field positioning of grapes. Perhaps in the future we will see these autonomous tractors lighting up fields at night.

Frost damage

The French prevent early bud loss by using fire candles between vines. It’s a risky business balancing crop loss from frost with fire damage if not controlled. Water sprays are often employed to protect against frost damage by forming ice crystals around the buds during cold weather. 

Microclimates play a significant role in wine quality and cool ocean breezes inland result in thicker skins on the berries resulting in more color, tannin and concentration of flavor.

Field light spectrum can assist fruit bud development 

Improving knowledge of environmental triggers for bud burst in grapes can help to optimize plant productivity, especially in marginal climates. In particular, an improved knowledge of the physiology of bud burst is fundamental to enable better crop management.

The point where a quiescent axillary bud commences regrowth is governed by both metabolic and signaling functions, driven by light, energy, and oxygen availability. Several grapevine studies have investigated the influence of low-intensity light on shoot physiology, suggesting that it is adapted to a low-light environment. Removing the apex can result in axillary bud outgrowth, as can changes in light intensity and quality. Axillary bud outgrowth is regulated by signals from the apex, which contain several light quality and quantity sensing pigments. These phytochromes sense red and far-red light, while cryptochromes and phototropins are involved in the perception of blue light. Accumulating evidence supports the function of photoreceptors in blue light perception resulting in activation of photomorphogenic gene expression, stimulating bud outgrowth.

Field trials with inter-canopy LED lights in California. Reach out if you need advice, we are here to help. 

These photoreceptors regulate the expression of different transcription factors to coordinate light-dependent photomorphogenesis. 

An early indicator of the transition to bud burst is ‘sap-flow’ preceded by an increase in xylem pressure leading the an increase in auxin and sugars in the sap.

Applying light theory helps improve knowledge of the physiology of bud burst which is fundamental to better canopy and crop forecasting, as the timing and coordination of this event will influence flowering, fruitset, and ripening.

Indoor low intensity RB LED lights – in Scotland year 2 with no trusses but plenty of tendrils and good vine growth.

Pests

Leafhoppers, cochylis and Lobesia botrana are dreaded pests that cause considerable damage to grape crops. IPM plays an important role in scouting for early damage to prevent disease. Prevention by spraying crops with regulated fungicides helps limit damage.  

Micropropagation of new grape varieties 

Starting Clean

Fungal and viral infections have plagued vineyards particularly in California where in the 1980s the deadly root infection phylloxera returned, completely devastating vines planted on AXR1 rootstocks. 

Viruses reduce plant vigor and delay bud break, and can be transmitted through vegetative propagation. Rapid micropropagation techniques can produce clean, disease-free, and vigorous plant material in a shorter time period, compared to conventional propagation techniques. 

There are many reasons why breeding is important to the wine industry, and my friends at PCT wrote a neat article on why growing clean clones is one of the most efficient methods to scale grape plantlets. 

New growth from a nodal cutting of my black Hamburg in initiation MS media growing under different low intensity LED spectrums.

A number of micropropagation techniques can be employed to clone grapes. Meristem culture induced from nodal cuttings can help to eliminate endophytes and produce virus free clones like above. 

Sweet seedless grapes like cotton candy are produced via embryogenesis. Others like Selma Pete, a white grape, are grown for the raisin market. The power of breeding a particular variety for a select market can pay dividends. 

Health properties of grapes

Health properties of grapes and grape juice are well documented particularly the black varieties which have higher anthocyanin levels, with known anti-inflammatory properties. Grape juice is a great way to boost immune systems and stay healthy. What we do know for sure is that resveratrol is well absorbed in the body and offers some exciting anticancer properties. Probably best to consume through black grape juice if you are concerned about the alcohol content in wine. 

Turning grapes into wine 

‘The older the vine the better the wine’ is a common saying in the industry, meaning the skin to pulp ratio increases creating a more intense flavor. Vines can be anywhere from 20 years to 120 years old and still produce good quality fruit. Some growers also believe older vines with deep root systems are more efficient at transferring minerals. 

One thing’s for sure, there’s more science in wine making than you can shake a stick at! It’s chemistry without cooking. Even for hobbyists it’s a great pastime and relatively cheap to get started. As a student I was taught how to make wine in demijohns, it was a relatively simple process. Yeast varieties can also have a significant effect on alcohol production. My final year degree project was to establish the budding rate of Saccharomyces cerevisiae, the most common species of yeast in winemaking. Ah, that stirred tank fermenter with all those sensors, part biology, part engineering…..

Begin with good quality grapes and crush and press down hard until the bunches are smashed and the juice is released. For reds, ferment the juice, skins and seeds after removing stems. 

At least 5 gallons of white grape juice can make five gallons of wine. Pour the juice into a demijohn. White grape juice is green to start and as it oxidizes it will turn a brown color during fermentation. Add wine yeast at a comfortable room temperature. It will foam as it releases carbon dioxide within a day or two, which signals the start of the process. Use an airlock to keep oxygen out and allow the carbon dioxide produced by to escape. 

Red ‘must’ can be fermented in a large open container with just a towel, add wine yeast, and give it a good stir. It may begin to ferment in as little as 12 hours.

Red wines need to be stirred, at least twice per day when fermentation is going strong. You’ll see skin floating on the surface but just stir down regularly. Red wine should be around 80°F during fermentation. Test the sugar levels of the fermenting juice periodically with a basic hydrometer. It’s measured in degrees Brix, which equals sugar percentage will reduce to -2 Brix once fermentation is complete.

When the wine tastes like something you’d enjoy drinking, it’s time to bottle. Most white wines should mature after four to nine months whereas reds may take from six months to a year. You can learn more about winemaking from a course at Cornell or perhaps the ‘personality’ of wine from Jancis Robinson, an influential wine critic. Wine will benefit from a few weeks or months aging in the bottle, but who can wait that long? 

My top reds are Spanish and Italian and I’m partial to a Californian rose. Chris would not say no to anything from the Napa Valley. Slàinte Mhath. 

Janet Colston PhD is pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

Unless otherwise stated all images are courtesy of The Functional Plant Company and property of Urban Ag News.

We know light exerts a powerful influence on plant growth. These effects can range anywhere from seed germination to leaf expansion and from flowering to fruiting. But, did you know it’s not only plants that benefit from changes caused by light? Human health can also be boosted by light induced changes in the fruits and vegetables we eat. These systems are interconnected. Read on to find out how CEA farmers could hold the key to both higher crop yields and better human health through the smart use of spectral low intensity LEDs.

Color Survival

As humans we cannot survive without food, water, air, or shelter. Some maybe curious to go further in asking what’s the point in just surviving if you don’t live a healthy, and colorful life. So, what do we really mean by a colorful life? Perhaps the ‘joie de vivre’ could be loosely defined by variety, intensity, and vibrancy in our lives. The similarity to the definition of color, is patently obvious, correlating with chroma, value and hue. We want to show you how interconnected and highly dependent we are on light and color in growing fruitful crops with health promoting factors (aka; Natural products/Specialized Metabolites).

As farmers in CEA we are at the forefront of lighting technology, pushing the boundaries of understanding in the requirement to produce the best quality crops with the greatest impact on our health. Often we are told to ‘eat the rainbow’ in order to provide a range of nutrients for health. With this in mind it is even more important than ever for growers to use their knowledge and appropriate technology to increase their value proposition with efficient growing and marketing of their products.

What are the elements that make up color? 

We see the world in a multi coloured spectrum of reflected light wavelengths. Of course ‘visible’ light is only a small part of the wide spectrum which as a whole also includes ultraviolet, and far red wavelengths. Structures called cones (rods are used for night vision and low photon light) in the back of our eyes refract visible light like a prism below to send a signal to our brains which helps us distinguish colors. Most often in life we see visible light split into its constituents when a rainbow forms and electrons are diffracted through raindrops. How much color is relevant and used by a given plant, we aim to find out. 

Light penetrates air, water, and through our shelters if we don’t block it out so we must gather data on how much radiation traverses the greenhouse and other structures which give shelter to crops. Integral to this is the daylight integral or DLI, the optimal amount of light a plant needs over a day. This helps us establish when to add further efficiencies with supplemental light and tailored spectral recipes. 

How do plants perceive light? 

Plants are dependent on their ability to sense and interact to their surroundings to optimize their chances of survival. What happens in the plant world is very interesting and light has several known actions on plant growth and development.

Deeper in the chloroplast within the thylakoids lie the photosystems that serve as the site for absorption of sunlight. Special structures called photoreceptors detect an array of wavelengths, allowing them to ‘perceive’ light and send a signal in the direction of growth. Similar to human eyes a wide range of photoreceptors exist, including phytochromes, cryptochromes, phototropins and ultraviolet-B receptors help plants discriminate light signals from ultraviolet to visible to far red wavelengths. Of course it’s much more complicated than we can talk about in this short article but essentially the plant has a control mechanism that distinguishes wavelengths through these photoreceptors and a metabolic switch to biological reactions.

In summary the leaf interface acts as a mini processor, where energy from excitatory photons hitting the thylakoids catalyze the photosynthetic pathway between carbon and water to produce glucose and oxygen. This directly impacts cell signaling, including metabolic, morphological and physiological changes in plants.

It is important to take into account not only spectrum but also efficacy of LED lamps as this determines the number of photons hitting the leaf surface. This means lights should be balanced for growth and less likely to be separated as defined by the image below. Instead they are low intensity LEDs incorporating blue wavelengths and appearing white, or balanced red and blue wavelengths, the latter appearing pink. It is important to take advice from a quality LED vendor and compare the market as not all LEDs are equivalent quality. Reach out if you need advice.

As more academic research into LED lighting becomes available, increased awareness of specific wavelength induced changes will help efficiency in new crops for higher biomass and increased stable levels of health promoting specialized metabolites for human health.

Can varying spectrum LED lighting increase crop traits and efficiency?  

Light exerts a powerful influence on most vegetable tissues, and there can be no doubt that it generally tends to check their growth” – Charles Darwin, 1880 (The Power of Movement in Plants)

In CEA we have the advantage of an agricultural phenomenon that can harness data on each of the nine environmental variables that impact yield including diffracted wavelengths. This ultimately helps refine and optimize processes for farmers.

Different wavelengths help plants achieve various goals. In general plants exposed to blue light encourage vegetative leaf growth, stem elongation and rooting whereas red light, when combined with blue, switches on genes for plants to flower and fruit. This is not surprising when experiments show an increase in chlorophyll content in the PAR range of the spectrum. Green wavelengths reflect most light (hence why we see them as green) but this specific wavelength is known to be responsible for deeper canopy penetration and absorption balance of excess energy in some plants. The latter is an important physiological step, often overlooked as not all energy is used in photosynthesis (remember it’s rate limiting) and excess energy must be dissipated safely as heat.

Although we class the photosynthetically active region (PAR) between 425-695nm, a nice study by Paul Kusuma at Wageningen showed the power of far-red photons influencing leaf area and stem elongation. Essentially the higher ratio of far red light can help plants stretch at night. He also found lower energy of far-red photons makes them useful in reducing electrical power inputs.

UV light on the other hand can be used in pulses to disrupt bacterial DNA and prevent disease in plants. Short term UV treatment has been shown to  improve performance for both seedlings and seeds that deliver long-term benefits, including improved crop consistency, increased yield and stronger disease resistance. This can increase the chance of producing healthy plants without viral invasion. As Darwin succinctly suggested, light provides nature’s way of balance. 

Learn more from the experts in horticulture lighting spectrum here.

Different wavelengths in Turmeric

When plants are grown in tissue culture, light, humidity, and nutrients can be tightly controlled. Although TC is an artificial state with immature leaf structure, it could be useful in predicting a smart spectral recipe, taking into account the lack of stomatal development. Low light intensity LEDs are typically employed as a strategy to prevent heat damage in immature propagules but different wavelengths could be more advantageous for certain desirable traits. For instance red, blue, and green LEDs have been found to have specific effects on plant growth rate, developmental characteristics, and production of bioactive specialized metabolites. 

We used turmeric as an example of how to control light for different growth and specialized metabolite requirements.

Under low intensity LEDs, we can encourage rooting in turmeric but also elongation of shoots. We can also combine factors we know control growth like levels of plant growth hormones, humidity, gas exchange, liquidity of substrate and additions like activated charcoal to help some species like turmeric root better and this can also increase plant biomass. Good rooting and biomass gives plants a head start during acclimation. 

Turmeric shoots multiplied under Arize Lynk LEDs (red blue) as they continue simultaneous growth of both leaf area and roots in the multiplication phase. It’s not always desirable to let roots grow out in the multiplication phase as they tend to be more vulnerable to infection particularly if using high sucrose as a carbohydrate source. Reducing the ratio of blue can help reduce rooting during this stage. When in the multiplication phase, the level of cytokinin (shooting) to auxin (rooting) is increased but we also can utilize light to control growth as desired.

Acclimation

As turmeric acclimates and the plants develop mature leaves, Arize Lynk LEDs  are better for leaf growth and an advantage to increase foliage biomass. We know from other studies that turmeric grown in the acclimation phase, under RB spectrum increases phytochemicals, such as polyphenols, flavonoids, sugars, and boosts curcumin biosynthesis. 

Turmeric is a perennial spice that can reach a height of about 1m. To increase turmeric rhizome size requires higher light intensity light and increased oxygenation of roots during the growth stage taking up to a year to produce good harvestable yields in different systems. Prior to harvest, farmers should consider supplemental RB light and higher intensities, to increase anthocyanin content. 

While we do not have the results from studies of isolated green light, we postulate that green light is efficiently absorbed deep into the canopy during rapid growth periods. If you time the crop season right, natural sunlight allows for a reduction in energy consumption while using the whole visible spectrum more efficiently (that is if wavelengths are not deflected from the structure you are growing within). 

Growing plants like turmeric in CEA for the entire crop cycle is unsustainable and farmers should consider hybrid models to produce the best results and yields for the end user product and market they target. For instance if the product is for specialized metabolites then by all means grow and process in as close as possible to sterile environments but if the market is for color and curry, open fields are more realistic. 

The power of hue in health. 

Did you know sir Isaac Newton invented the first color wheel in 1666? I did not!

Artists have studied and designed other wheels based on Newton’s concept. Most color wheels have a total of 12 main divisions (as we see from the chart), but then subdivided again we have 24.The primary colors are red, yellow, and blue. The secondary colors are green, orange, and purple and the tertiary colors are yellow-orange, red-orange, red-purple, blue-purple, blue-green, and yellow-green. The problem is that color is not a quantifiable way to determine the anthocyanin content of a given fruit, leaf or rhizome. 

The Munsell color scheme on the other hand could be the way to distinguish higher levels of anthocyanin. The color scheme comprises hue, value, and chroma. Anthocyanin pathways are complex and often unstable due to oxidation but if stabilized using supplemental LED lights it could be a quantitative roadmap. Using the Munsell system could help us understand color related health values in the same way that brix value quantifies sweetness in fruit sugars.

A change in the color of plant skin, leaf, fruit, and rhizome indicates when plants are ready for harvest. But do we ever consider we can control this process? It’s called the stress reaction in plants. Some fruits with purple skins will have higher Munsell values. We can correlate color intensity of blueberries, blackberries, strawberries and raspberries with higher levels of antioxidants. As a fluorescence scientist I know there are many spectrophotometer devices that could be used to quantify color values. An example of color versus phytonutrients can be seen in bilberries. Bilberries exhibit darker hues than farmed blueberries and have significantly higher anthocyanin content compared to the latter. Could we, in the future, have a hand held device for farmers to know the level of anthocyanin?

Other research articles reviewed the targeted use of LEDs, i.e. blue range (400-500 nm) of spectrum and found blue light is efficient in enhancing the accumulation of phytochemicals.

The flavonoid Curcumin in turmeric trapped in vesicles can range in diverse yellow-orange hues. Curcumin is a bright yellow chemical compound that gives turmeric its color. It is not readily soluble in water, but is in other carriers. Electrons in the curcumin molecule absorb energy from ultraviolet light and move to a more excited state. Try this interesting experiment if you are a teacher, it will get your students attention.  

Stability of phytonutrients.

Curcumin in turmeric has been well proven in the lab to kill many types of cancer cells. Why does this not translate to the body? The biosynthetic pathways are highly unstable and curcumin has extremely low bioavailability. It is only when curcumin is combined with piperine that we see positive effects. Even then, the marketing of products containing turmeric has led us to believe they can cure ALL ills, when they cannot. We are not insinuating these functional plants don’t have potential, but we are concluding it is dependent on stability and bioavailability of active metabolites. 

If you read our personal health journey’s you will discover like we did the best kept secret in medicine; that is if you are ill, a colorful plant based diet will give you a fighting chance. 

Image of different zingiberaceae species courtesy of our friends at Spade and Clover, Johns Island, South Carolina. 

Should we continue experimenting with environmentally friendly ways to produce the healthiest plants?
Absolutely, there is more to discover. 

We know there is variability in the level of curcumin in commercial turmeric and native turmeric alone has low bioavailability. This means that, under normal circumstances, little is absorbed from the gut into the body. Increased stable levels of specialized metabolites could have potential to produce similar metabolic and physiological effects to what we see in the lab. 

Light up your plants for Specialized Metabolites
Increasing the quantity and quality of curcumin using low intensity spectral LEDs at the correct time in the growing cycle can increase important specialized metabolites possessing various pharmacological properties providing increased carrier opportunity to cross membranes and produce stable physiological effects.

Is a turmeric based curry the healthiest meal you can eat?

In India, turmeric is commonly known as “haldi” (Sanskrit; haridra). 

• Preceding Vedic culture, turmeric has been used for more than 4000 years in India, where it was used as an edible spice with ceremonial significance still practiced today. 
• According to Ayurveda and Unani systems, turmeric has a long history of medicinal use in South Asia. In fact, in 1280 Marco Polo talked about turmeric as the new wonder spice having qualities similar to that of saffron. 
• Susruta’s materia medica (250 BCE), mentioned a formulation of ointment containing turmeric as a major ingredient, having anti-inflammatory properties which helps in reducing the effects of food poisoning.

Indian recipes are a great way to boost the immune system, reduce inflammation, and improve cognitive functions. Turmeric and black pepper together have impressive health benefits, due to the metabolites curcumin and piperine. As piperine enhances curcumin absorption in the body by up to 2,000%, combining the spices magnifies the effects. You can read more about growing turmeric and the beneficial health effects from our previous article. 

Now if this doesn’t inspire you to make a wonderful healthy grain inspired curry, and buy the freshest ingredients from your local farmer we haven’t done our job right. 

All Images unless otherwise stated are the property of Urban Ag News, please ask for permission to reprint our articles. We are indebted to our friend Dr Shashank Saini for his diligent review of this article.

Janet Colston PhD is pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

Unless otherwise stated all images are courtesy of The Functional Plant Company and property of Urban Ag News.

“You should never hesitate to trade your cow for a handful of magic beans. “ — Tom Robbins 

 Protein Replacement is a hot topic 

Nutrition and protein replacement in particular is a global health concern with implications for the future direction of the planet, not least because the tide could be turning on less sustainable types of food production. We have had some in CEA evangelizing about the power of CEA to feed us all in the future, but the reality is that we need all agricultural practices to work together where appropriate to create resilient sustainable supply food chains close to where people live. Given this opportunity we should consider how we assist the creation of new plant proteins in hi tech towers and glasshouses. It is with this thought in mind that we could be overlooking the potential of the fabaceae family which includes legumes (pulses are the edible dry seeds) that have sustained entire continents in times of need.

Getting real with alternative proteins 

We want to explore if pulses and specifically beans grown in CEA could provide complementary protein to that found traditionally in meat, dairy, fish and more recently, cellular meat (which is different from plant based burgers that incorporates soy, wheat, potato or mushroom protein). It should be noted that cellular meat also uses soy protein for scaffolds i.e. a lattice for cells to grow into 3D meat.

Let’s begin with an argument. Many in the medical community advocate a plant based diet to be wholly adequate to supply all the body’s protein requirements. Others argue that plants do not contain an adequate source of protein and that animal protein is essential for supplementing our diets. It could be time to challenge the assumption that ‘real men eat meat’. Whatever your stance, we do know that essential amino acids, thought to be less abundant in plant based diets, could in part be provided by chickpeas and soya beans, helping to supplement vegan or vegetarian diets. Make sure you add seeds, nuts, whole grains and lentils to ensure you get all nine essential amino acids. If you are worried about the lack of Vitamin B12 which cannot be provided by vegetables, try a source of shiitake mushrooms or nori seaweed in your diet. 

‘Beans are a great value for money meal and source of protein during the cost of living crisis’

While I’m old enough to have visions of Mel Brooks blazing saddles around the campfire, there are so many delicious recipes that create a heart warming meal from a range of pulses, legumes and lentils. Theoretically speaking it is better for the planet too if we consider biogenic methane production from a cow’s four stomach chambers versus our human gut should we consume more beans as our protein source in preference over animal protein. 

A trick to avoid gas: Eat more beans! Why? We often lack an enzyme called alpha-galactosidase produced by gut bacteria. This enzyme helps break down complex sugars that can, if not fully digested, cause excessive wind. As your body gets used to eating more beans (they act as a prebiotic to increase the good bacteria), more enzyme is produced in the gut to digest these carbohydrates. 

Beans are a staple in the diets of many underdeveloped countries, they taste good in meals and can in fact cost far less than meat based stews. They are also on a calorie ‘like for like’ basis much better for your health as well as being cheaper to produce. So the question then becomes, can we grow them close to where people live and in large enough quantities? 

Many people are unaware that chickpeas and other pulses contain components that when eaten as part of a balanced plant-rich diet, help prevent the development of diseases like diabetes and heart disease. These beans have a soluble fiber called raffinose, which is fermented in the colon by beneficial bacteria and has been shown to reduce inflammation. Chickpeas also contain a cholesterol like plant sterol called sitosterol that can trick the body into lowering blood cholesterol levels. The satiating effect of the high fiber and protein content of chickpeas may also help with weight management, another major factor in lifestyle disease progression.

The practicality of growing bean vines in VF like many other plants is dependent on the number of plants per square foot, breeding programmes to increase nodes (spectrum is likely to play an important function in early flowering) and compliant technology. Research into the economic efficiency for well designed CEA facilities (lights, oxygen, fertilizer) and indoor grow rooms should be considered versus higher energy outputs when considering new crops like beans. But, with quick production cycles and all year round growing potential, farms could easily be adapted much like other vines such as tomatoes and chillies to grow unique high protein legumes. They could even be tacked onto the side of existing horizontal structures with additional inter-canopy lighting. High production cycles are likely to determine profitability so modeling through trials is recommended.

The Functional Plant Co in Scotland have been studying beans like Lima and ways to increase nodal development in CEA TC to produce high quality slips for continuous batch supply to plant factory’s.

Native American Beans are steeped in tradition 

Pole beans were a staple of Native Americans with more than 5000 known varieties spread worldwide. They have a long tradition in Native American culture including the Hopi tribe, whose Bean Clan is called Murzibusi. Such importance has been associated with beans, that some eastern tribes, like the Lenape, Shawnee and Iroquois actually have a ‘Bean Dance’ amongst their tribal dance traditions. Despite myths of their Mexican origins, Anasazi beans are thought to have been cultivated throughout generations of Southwestern Native American tribes. Today these beans are commonly used in many Latin American and Southwestern cooking turning pink once cooked, and are often used in refried bean recipes due to the sweetness. Remember it was the Indians that invented succotash with sweetcorn, lima and other mixed beans.

The Many Health benefits of beans 

Regular consumption of beans has been linked to disease prevention, including cancer, diabetes and heart disease.

Beans have a strong nutritional profile, marked by a high amount of iron, calcium and potassium per serving. As well as antifungal, antibacterial and antiviral properties, beans have a low glycemic index and are found to be high in lectins, a glucose-binder, with potential to avoid sugar spikes and naturally treat diabetes. If that wasn’t enough, the anti-inflammatory effects of these magical beans may also help you fight cancer.

The Color Purple 

The red/blue color of beans is due to a group of biological pigments called anthocyanins. This same group of compounds is also responsible for the rare blue pigments we see in nature.

Nonna Agnes Beans

An analysis of black beans showed most of the anthocyanins to be delphinidin, with lesser amounts of petunidin and malvidin. Delphinidin and malvidin are responsible for the blue color in various flowers. Petunidin is described as having a dark-red/purple color adding to greater health benefits.

Growing Beans in CEA

One of the most commonly used Native-American gardening techniques was ‘Three Sisters’, probably the first no till agriculture method on the continent. They planted corn, squash and bean seeds together. The beans provide nitrogen for the soil, the corn was a natural trellis and the squash a canopy to deter pests. 

The three sisters’ companion planting originated from native Indian farming of maize, beans and squash. 

Respectfully we’ve come a long way since then but as we look for protein replacements, beans are a natural choice to incorporate in CEA farms. 

From three sisters to one grandma, Nonna Agnes pole bean, one day post germination in high strength Gibberellin. 

The seeds of Nonna Agnes, a pearlest blue heirloom bean from you guessed it, Italy, germinate in a day with the hypocotyl peeking through the outer layer and reaching for light via tropic geotropism. The strength in beans is phenomenal as the large carbohydrate seed store forces the tap root downwards and shoots up. 

In normal soil production this can take several days longer than germinating in a controlled environment. Obviously the stronger the young plants, the more vigorous they are and with inter-canopy spectral LEDs it is possible to force flowering much earlier than in the field, with higher yields in a shorter time frame. 

These modest-looking legumes pack a mighty health punch. In addition to being an aforementioned protein source, they are an excellent source of fiber and act as a prebiotic, providing a nutrient source for beneficial bacteria and microorganisms that make up the gut biome in our digestive tracts. 

Let there be light amongst the vines 

If we are to grow these kinds of crops in CEA we need internodal spaced LEDS or a vertical hanging design to ensure efficient light intensity delivery to ripen pods. We already grow tomatoes with aerial LEDs so alternative vine crops like beans should be no different. Much will come down to modeling of economic returns. New technology emerging such as intercanopy lights to grow indoor vines will also add to biomass with higher yields and increased flowering during off peak times of the year. Choosing low light varieties that are bred with increased nodes will have a big impact and can help growers switch during tough times for high energy costs. Beans are a perfect example crop that have enough variety to experiment with low light varieties. From the beans I tested, Amethyst, Lima and Pole viola do assiago all produced flowers in two weeks with one TLED at 100umols/m2/s followed by pods in 2-4 weeks and a small harvest in 6-10 weeks. 

Faba beans flowering under Currents RB balanced LEDs in Scotland during autumn with average day temps 15-20 Celsius and night lows of 6-10 Celsius. 

Soybean pods filling up

Another member of the fabaceae is Bambara (Vigna subterranea (L.) Verdc.), an African equivalent of American peanuts growing from extended rhizomes. Also called the Congo groundnut, it is a fast growing plant, but needs warm temperatures over 150 days cultivation. Recent studies have found it to be very high in protein, providing all of the daily nutritional requirements of protein, carbohydrate, unsaturated fatty acids and essential minerals (magnesium, iron, zinc, and potassium). The waste greens can be fed to livestock adding to nutrition and sustainable agriculture. 

Unusual varieties like Bambara could be grown in locations previously unheard of, circumventing international supply chains and reducing carbon footprints. 

In Africa these beans are grown on small-scale subsistence farms by women, in a rotation with other crops like maize to fix nitrogen in the soil. Despite interest from international companies attracted to its high protein content, the supply chain for Bambara is not yet secure. An opportunity awaits CEA farmers with a warming climate. Perhaps even Texas could become a great location for a new crop. Germination can be slow because of the hard seed coat but once released from this we can use growth regulators to increase germination rates in addition to trialing micropropagation techniques to produce high quantity slips. 

Nonna Agnes Beans developing under Currents RB balanced TLEDs indoors in Scotland above.

Amethyst bean pods to the right and harvest below, the color change is evident in the last week of production.

How we preserve these crops for the future 

There is no doubt beans are cheap, sustainable (you can save some seeds for next year), easy to grow and packed full of protein with great health benefits suggesting they are not only good for the cook-book but also for the planet. Variety is key to the success of beans and we hope you look further afield (intentional pun) to incorporate these fine pearlest beans as a regular CEA crop.

Don’t know where to start? The Crop Trust in Svalbard, an archipelago off Norway holds a massive bank of beans, conserved from farmers across the world. Of course this is worthless if farmers don’t have access to or take the opportunity to grow these conserved varieties. You can only request samples from depositing genebanks. As the seed bank shows, the way forward is cooperativity between growers around the globe. Breeding of heirloom varieties as well as processing via partners and marketing sustainable protein replacement to consumers will encourage the FMCG industry to create healthy plant based protein products in the future.

Janet Colston PhD is pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

Unless otherwise stated all images are courtesy of The Functional Plant Company and property of Urban Ag News.

Zafferano Siciliano Crocus produces large saffron stigmas.

Saffron (Crocus sativus L., a member of the Iridaceae family) is prized for its unique yellow color in culinary dishes and loved by chefs for its flavor in many of our foods. The high cost comes from the fact that it needs to be grown in a particular climate and the long red stigma must be laboriously collected by hand. 

In the US, saffron is traded for up to $10,000 per kilo but this is highly dependent on the final graded product (graded 1- 4, 4 is the best quality and has a high safranal content with the red stigma separated from the yellow anther). The problem is, it takes around 150,000 flowers to produce 1kg of dried saffron. So we want to know, is it really worth it for CEA farmers? Let’s take a closer look at saffron’s history and the pros and cons of growing the most expensive spice in the world.

A long illustrious history of production 

Ancient artworks revealed saffron was domesticated around 300 to 1600 BC and was thought to have been originally harvested as a mutant of Crocus cartrightianus which was abundant around the time in the Mediterranean.

The origins of saffron agronomy date back to Iran and today the country is responsible for producing over 90% of the world’s saffron where it has both historical and ceremonial importance in Persian culture. Other areas of production stretch across the Mediterranean where conditions are perfect for growing most notably North Africa, Morocco, Spain, Greece, Italy and India. The Spanish love the color in traditional paella whereas the Italians use it for signature risotto dishes like Risotto alla Milanese. 

How does it grow naturally?

Visible two to three flowers per saffron corm

Saffron is adapted to arid regions and has an annual life cycle, but it is generally cultivated as a perennial crop by controlling corm bulb growth for the following year. It is a sterile triploid geophyte and is relatively slow to replicate through daughter corms each year. In the field, corms that die back after flowering and unusually have no cold requirement to break their dormancy. They can be lifted from the field during this time and stored in a dry shed before planting out again in spring, although they are hardy and can withstand low soil temperatures. 

Saffron has immense health benefits 

Saffron is abundant in phytochemicals, particularly picrocrocin which breaks down during the drying process to form safranal, which gives it the distinctive earthy taste. Another carotenoid pigment crocin, produces the golden yellow color when mixed with rice. Saffron also contains non-volatile antioxidants including lycopene and zeaxanthin which we identify with a Mediterranean diet, that are great for a long healthy life.

Crocus sativus L. has a wide array of medicinal and nutritional uses. Traditionally it goes way back as a drug alternative for many conditions such as heart disease, obesity, Alzheimer’s and diabetes. Several studies confirm the medicinal effects of the plant. Antioxidant effects demonstrate free radical scavenger activity that modulate inflammatory mediators, humoral immunity and cell-mediated immunity responses.

There are several clinical studies of these effects in its derivatives, safranal, crocin and crocetin. Researchers in Iran recently identified saffron as an effective treatment for mild postnatal depression. Saffron has since been shown to have mood altering effects thought to be the result of balancing neurotransmitters serotonin, dopamine and norepinephrine in the brain. In placebo comparison trials saffron had significant effects on levels of depression and displayed similar antidepressant efficacy to pharmaceuticals. 

A double blind study of more than 80 people found the effects of the spice effective in treating depression in adolescents, without any side effects or fear of withdrawal symptoms when stopping the saffron. Saffron extract (affron®) was given for 8 weeks and it was found to improve anxiety and depressive symptoms in youths with mild and moderate symptoms. Adults reported more mixed results so more studies are needed to be conclusive in the understanding and role of saffron in the treatment of depression.

Why do we need high value crops like saffron in CEA?

Growing saffron in a controlled environment can have many advantages; it’s cleaner, free from pests and disease, nutrients are delivered directly to the root mass, aeration with dissolved oxygen increases biomass, temperature can be maintained without fluctuations and light intensity can be well managed. Saffron needs high intensity light and this can be delivered by high efficiency LEDs without fluctuation, eliminating weather dependent uncertainty in the field. 

Despite the relative ease and low maintenance of growing in a controlled environment, it is the high flower numbers required to produce the end product and subsequent labor intensive ‘picking’ time that are the limiting factor. While in the field it is possible to grow three or more flowers per bulb per season (due to the daughter corms still being attached) the spacing requirements are more difficult to estimate in CEA until trials show optimized growth in a square meter space as smaller daughter corms will produce smaller stigma. We have no knowledge of large scale CEA production data and comparison to field harvests but scaling up in CEA may be more prohibitive due to labor costs. Perhaps automating this process in the future with robotic tweezers or re-engineering tissue culture pickers to use image analysis software with an ability to pick out the red stigma and separate from the anther would be useful, but we are some way off that at present.

Saffron has a high Market Value 

Regardless of the issues, saffron continues to be of interest to CEA growers due to its high value and growing global demand as a medicinal plant and diverse applications in the food industry as well as for cosmetics and dyes.

The global saffron market size is expected to reach USD 721.5 million by 2028, according to a new report by Grand View Research, expanding at a CAGR of 8.5% over the forecast period.

Buyer beware! If you buy saffron and it seems cheap it’s more than likely to be fake!

Fake saffron is rife within this market and includes corn silk threads, safflower (an unrelated thistle), coconut filaments or even dyed horse hair, or shredded paper. 

Safflower (in tissue culture above) Carthamus tinctorius, is the most likely culprit. It is a highly branched, herbaceous, thistle-like annual plant in the sunflower family Asteraceae and is often substituted for saffron. Each flower head contains 20–180 individual florets that can be confused with saffron to the untrained eye but the color gives it away as they are less intense than saffron stigma. 

Dyes used to color fake saffron will dissipate quickly and this can be tested easily in water. Despite this, safflower has some excellent qualities as an oil in its own right and is commercially traded in the EU. 

Growing conditions 

Temperature, light intensity/spectrum and humidity are particularly important in saffron cultivation. According to researchers in Vermont there are five main phases to the lifecycle of saffron production, sprouting, flowering, vegetative phase, production of replacement corms, and the dormant phase. Leaf area index, crop growth rate, relative growth rate, net assimilation rate, and leaf area ratio are all important.

A few entrepreneurs are paving the way by growing saffron in CEA. Dr Ardalan Ghilavizadeh pictured above is an expert hydroponics saffron grower from Iran and currently working in Munich.

Saffron is a short-day plant so requires a period of around 12 hours in the dark and 10-12 hours per day lights on (16-18hrs during flowering). According to Urbanleaf, saffron can be grown indoors and they suggest it will require a DLI of 15+ mols/m²/d to flower. They go on to propose that 24W light bulbs can be placed around 6 inches away from the top of the plants to deliver a PPFD of 500 μmol/m²/s. Ideal temperatures for saffron flowering are around 70°F but anything between 50 and 100°F grows well. We have some preliminary trials with saffron but experimenting with light spectrum may achieve the best results to promote flowering and maintain a stable temperature during flowering. Growing in hydroponics follows similar conditions to other flowering plants and saffron displays a wide pH range of 5.5 – 7 but it’s best stay around 6 for maximum nutrient uptake at EC 1.4. 

As with any production, IPM is important since saffron is prone to many diseases. Pathogens include fungal corm rot, nematodes, bacteria, and viruses. Diseases mostly appear as a consequence of physical damage or attacks by insects particularly mites and aphids.

Propagation of Saffron Corms 

Saffron male seed is sterile so it is propagated vegetatively using corms. Flower yield is highly dependent on corm size and density but lack of availability and diversity of plant material presents a major constraint for large scale CEA saffron production. A large corm above 8 grams produces three to four small daughter corms, which take 2 to 3 seasons (in the field a season is one calendar year but in CEA there is potential for four harvests annually) to achieve the size and weight for flowering. 

Forcing the bulbs through regular dormancy periods via CEA may help to promote cormogenesis.

Crocus sativus corms like rock wool for support to protect them against getting too wet. The method of hydroponics i.e. NFT or aeroponics must not allow the bulb to get too wet so it should sit proud of the rock wool substrate. They will root very quickly, around a week in our experience with aeroponic growing. 

Saffron Micropropagation 

Saffron is relatively slow to propagate and only produces a few vegetative corms on the main plant annually in late summer after flowering has finished and the leaves die back. Breeding programs are needed to increase diversity of the corms and micropropagation may provide a solution to access of clean stock material. Saffron research is limited with only a handful of teams working on genetics in India, Iran and Europe. This crop needs preservation of genetic biodiversity to protect its quality and sustainability for future agricultural production. 

Genetic diversity in corm supply is an issue so indirect organogenesis may provide new routes to improve cultivation of saffron. Tissue culture micropropagation, somatic embryogenesis, organogenesis, gene editing and in vitro cormogenesis can all help regenerate pathogen free reproduction of this plant. We are working to perfect this process. 

Processing 

Harvest first thing in the morning according to Dr Sally Francis, a field grower from Norfolk in the UK. The stigmas must be dried soon after harvest as they can become moldy. Besides the important role that dehydration plays in the preservation of saffron, it is also a necessary process to generate organoleptic properties in fresh stigmas. Dehydration treatment brings about physical and chemical changes necessary to achieve the desired quality of saffron. But be careful drying as over 150F can cause degradation of the phytonutrients.

Economics of growing Saffron in CEA – is it worth it financially?

On a 1 meter square shelf with a light intensity PPFD of 500 μmols/m²/s we can potentially grow 150 saffron bulbs (and assuming they each produce one dominant flower) with a spacing at least an inch apart to allow for flower development. Assuming they are forced to produce flowers 4 times per year, this rate could produce 600 flowers in a 1m² area annually. If 150 flowers produce 1g dry weight, a yield of 4g of dry weight saffron is possible from 150 corms per square meter annually (four harvests).

Assuming a 10 layer shelf with lights spaced 20” apart, there is potential to scale up to 40g in a vertical space and 10 bays could reach 0.4kg (in reality it should be higher depending on how many flowers the corm produces). Depending on the grade this could net a return of $4,000. Not a bad return if you exclude capital startup costs. However high energy consumption and revenue costs may substantially reduce profits per meter square. Calculations are difficult as it will depend on an hourly rate for a picker and the uncertainty of rising energy costs could also hamper the return on running such a facility. 

Issues that affect future stability of growing saffron 

The adverse effects of global warming and climate change on saffron flower induction could alter the way saffron is grown. As the global north becomes warmer and extreme weather events become more frequent we will begin to find these crops in more protected geo locations. Wars and poverty also play a role in agriculture and instability in the region could lead to reduced world availability. 

Niche high value product for the food service market – is that why we should grow it? 

While saffron may not be an obvious choice for most larger commercial CEA growers, it should not be discounted as a high value crop for the service industry, fitting with more niche restaurant based container farms. Saffron is fairly low maintenance until harvest and some are even automating growing, which will reduce labor costs as the stigma can be picked by the restaurants when required without post processing and delivered straight to the chef’s palette. The advantage is it can be grown anywhere, close to restaurants, in cities and of course we are biased but it may also go well with sushi and a side of real wasabi.  

Janet Colston PhD is pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

Unless otherwise stated all images are courtesy of The Functional Plant Company and property of Urban Ag News.

Who fancies some blue food? Really? 

The theory of food colour confusion may originate from us being strongly aroused by foods on the red spectrum. Research published in Nature recently showed that we are more attracted to red coloured foods as they appear to signal better nutrition with higher calories in comparison to blue or green foods. Trichromatic vision evolved in humans as a response to improve foraging and may explain why we rely more on sight than scent when locating the most nutritious foods and fruits that are ripe and ready to eat. This is surprising to us as ‘leafy green’ farmers when we readily assume a green colour relates to health but the Nature study was more assigned to calorific colour arousal.

Although our brains may not easily accept the blue colour as natural, our bodies will probably thank us if we do as blue-green algae also known as cyanobacteria has some of the best health benefits.

One particular cyanobacteria has been studied extensively over the years

Spirulina grows naturally in alkaline waters and was recognised and farmed by ancient civilisations for its medicinal qualities. The Aztecs of Mexico have a long historical relationship with Spirulina. They farmed Spirulina in large lakes, then harvested and air dried the algae to form a hard edible ‘cake’. This was often mixed with other foods and used as an energy source as these ancient people recognised it as an important functional food. 

Massive health benefits that many people have still to discover

People who move beyond the colour tend to use blue-green algae for supercharging the immune system, controlling muscle spasms, detoxing heavy metals, eliminating candida, improving memory and increasing energy levels to improve exercise performance. It may also lower cholesterol and blood sugar, acting to prevent heart disease, heal wounds and improve digestion. Pretty impressive qualities for this single celled life form billions of years old. 

There are two main species of the blue green algae Spirulina, Arthrospira platensis and Arthrospira maxima. 

As the image demonstrates, they are made up of single cells containing chlorophyll filled vesicles that react to light and photosynthesize like plants. Cultivation of commercial algae usually starts the life cycle in lab culture tubes, doubling quickly under controlled conditions. This helps to eliminate contaminants. Spirulina is the largest single celled blue green algae and it forms spirals visible to the human eye which bunch together to allow a quick harvest and is now cultivated worldwide as a nutritional supplement. 

Spirulina is high in iron, calcium, magnesium, copper, beta-carotene and B-vitamins.

Apart from the high content of protein, Spirulina contains B vitamins, particularly B12 and provitamin A (β-carotenes), and minerals, especially iron. It is also rich in phenolic acids, tocopherols and γ-linolenic acid. Spirulina does not have a cellulose cell wall so it is more easily digested. Most people selling dried Spirulina suggest 1-8g per day to boost the immune system but be careful as too much can have negative effects so it’s best to start with the lowest dose. 

Some suggest Spirulina has the power to tackle world wide problems like malnutrition. The UN and WHO recommend Spirulina for it’s extremely high nutritional value and sustainability.  It has even been called the ‘world’s most sustainable food’ with the potential to end world hunger. The Pole Pole Foundation in the Congo were finalists in the Earthshot Prize recently. They are leading the way to teach communities in developing countries how to grow Spirulina as a supplement to prevent childhood malnutrition.

Could Spirulina be an alternative vegan protein source?

Would you drink blue milk? 

Many vegans are looking for alternative sources of protein. Spirulina might even be a protein source of the future and a substitute for cow’s milk.  Spirulina platensis stands out for being one of the richest protein sources of microbial origin having similar protein levels when compared to meat and soybeans.

Not to be confused with regular green Spirulina in its basic form, blue Spirulina is an extract of the active ingredient phycocyanin in its purest form. This concentrates the dried extract with higher levels of antioxidants without so much of the fishy taste of fresh Spirulina. 

But if you don’t mind using fresh Spirulina (it’s fishy so it’s much better to mix with stronger flavours) it will provide protein that is quickly and easily absorbed in the body compared to animal proteins which is a bonus as it contains many essential amino acids that the body cannot synthesize alone and are essential for tissue renewal.

Antioxidant and Anti-inflammatory

Fresh Spirulina is high in antioxidants, especially phycocyanin, the pigment which causes the blue green colour. Phycocyanin can promote blood cell regeneration, improve lymphocyte activity and improve the lymphatic system. Studies have shown this antioxidant scavenges and fights the free radicals that cause oxidative damage.

Spirulina is known to be alkalizing to the body which boosts beneficial microflora in the gut. Liver function is improved and this greatly increases detoxification levels in the body. Fresh Spirulina contains chlorophyll and phycocyanin both of which help to remove toxins such as heavy metals and other pollutants from the blood. One remarkable study in children who lived close to Chernobyl after the nuclear disaster in 1986 found that giving them a small 5g dose of Spirulina a day could reduce radionuclide rates by half in less than two months. 

Spirulina has Cancer fighting benefits 

Spirulina has been hailed as an anticancer superfood, but reading further into peer reviewed literature is important as there are some extrapolated and conflicting reports from doing a simple google search. So here we only present peer reviewed data. From our research low dose Spirulina has anti-proliferation effects on stomach cancer cells, human leukaemia cells and B lymphoma cells, inhibiting carcinogenesis. 

Eating Spirulina daily may lead to increased energy levels  

Fresh Spirulina is particularly good for energy owing to its high nutrient density. Since the algae has no cell wall to break down, digestion of all those nutrients is fast and efficient. It can make a difference to energy levels quickly after consumption. Fresh Spirulina contains constituents such as polysaccharides (Rhamnose and Glycogen) and essential fats that are absorbed easily by cells and theoretically aid energy release. More studies are needed to be truly conclusive though but with low toxicity levels in the body, it’s well worth your own trials. 

Spirulina enhances energy performance because it unlocks sugar from our cells. If you are suffering from memory loss, this bacteria added daily to your routine appears to have significant effects. It does this by protecting the brain from free-radical damage by increasing the activity of two enzymes: catalase and glutathione peroxidase, which fight free radicals and make the brain more resistant to aging.

But It’s not all good news 

Spirulina may exacerbate autoimmune reactions in some people who are susceptible. As such it may worsen symptoms of multiple sclerosis, lupus, rheumatoid arthritis and other conditions linked to overactive immune systems. It’s also not recommended for pregnant women or children or people on blood thinners like warfarin. Be cautious where you purchase Spirulina, as it may be contaminated if not bought from a quality source, leading to additional side effects.

Bioavailability: Should it be dried or is live culture better? 

If you search for Spirulina online you are mainly going to encounter powdered products. There is nothing wrong with these as most research was conducted on using powdered forms which still showed positive results. However some reports suggest fresh Spirulina has up to 95% bioavailability. This means that 95% of the nutrients including essential amino acids, all the B vitamins and antioxidants are absorbed straight into your bloodstream increasing potency by 45% compared with powder. 

How difficult is it to cultivate and commercialize?

Spirulina cultivation requires sufficient aeration, agitation and proper light intensity for enhanced biomass yield, cell productivity, specific growth rate and protein content. Biomass yield has the potential to reach up to 12g/l biomass in a closed reactor system. Urea seems to be a promising alternative source of low-cost nitrogen for Spirulina cultures and addition of mechanised aeration will significantly increase yields. 

But what about algal blooms? Are they the same Cyanobacteria?

Spirulina itself is non toxic but other forms of blue green algae including Aphanizomenon flos-aquae, grown and harvested in the wild, is often contaminated and leads to toxic conditions when out of control. 

Blue-green algae occurs naturally in lochs, ponds, reservoirs, rivers and the sea. This summer in Scotland it became a real issue. When the conditions are right, blue green algae will create massive blooms so large they can be captured by satellite imaging from space. Blooms are accelerated by leaching of fertilisers, with nitrogen and phosphorus runoff into the water course which becomes detrimental to other life forms by blocking oxygen and releasing toxic microcystins.

So it’s a logical step to grow these in a controlled environment and if market conditions continue to accelerate consumer demand for functional foods then growing these super algae in CEA could be highly profitable for farmers.

The largest US producer of Spirulina is based in California and they produce on an open 108 acre site, exporting to over 20 countries worldwide. There are disadvantages of open ponds as they do not reach high biomass productivity due to the difficulty of maintaining the optimum temperature and so they are restricted to tropical and subtropical regions. This is mitigated to some extent with large paddles constantly moving the ponds.

Despite this hefty competition, CEA could be the perfect vehicle for growing a crop that has incredible health properties, sequesters CO2 and can be grown in tubing to eliminate contamination. With LED lights and agitation, enhanced yields could be harvested year round. 

This could be particularly useful between the shoulder winter months to increase profits and farm skills where wholesale prices have the potential to return profits of up to $15/Kg . A rough estimate of 12g/L biomass can be achieved with a photobioreactor system incorporating PPFD 166 μmol photons m−2 s−1 with potential doubling every 2-6 days depending on the algal species chosen. Based on this, and assuming you harvest 50% at each doubling time, a microfarm running 100L tanks could harvest 0.6Kg every 2 days, giving a total annual yield of 106.2Kg and a potential maximum annual return of $1593.  Scaling up production will make more economic sense. Optimizing and automating additional technology (LED lighting, CO2 enhancement and state of the art infrastructure as seen with Algaennovation) may boost production but this must be carefully managed to balance a return on investment.

Learning and applying new ideas – food, fuel & carbon trap

We like to get people talking about the future diversity of CEA. This helps drive innovation and creates wider jobs and skills. At the same time we aim to help you better understand the science and health prospects of plants that could be grown in CEA.

Of all the ideas out there, maybe our favourite is the idea of an algae curtain. Glow in the dark tubes of algae obscure prying eyes from your space while producing your own superfood or fuel. 

Could plants literally fuel plants in a completely carbon neutral circular economy? Biodiesel produced using algae contains no sulfur, is non-toxic and highly biodegradable. This could have potential in offsetting CEA energy outputs and algae fuel cells could make home farms more economically sustainable in the future. There are so many applications for algae, some are even using it to extract CO2 from brewing. 

Whatever reason you have for growing Spirulina and others (chlorella) there is no doubt about this being classed as a superfood. 

Closer to home we like the way CEA farmers are looking to diversify their product range and kudos to On the Grow farms in Rockwall, Texas, growing spirulina alongside their microgreens. They grow in demijohn bottles adjusting the salinity to 2 and pH 10.5-11, harvesting and topping up fresh water every day. In order to maintain high pH and avoid fluctuations, high amounts of sodium bicarbonate must always be included in the culture medium to buffer the solution. The water needs aeration and temperature needs to be tightly regulated to 80F. LED lights will speed up production and your farm will literally bloom.

Spirulina first rose to fame as a potential space food. Maybe in space our brains are altered by gravity to be more accepting of blue food. Or maybe we will discover a whole new superfood bacterial species on Mars or deep in the ocean.

So who’s got a spare shelf in their vertical farm for this blue superfood and space age protein milk shake? 

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Janet Colston PhD is pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

You can follow The Functional Plant Company on Instagram. 

More from Janet Colston and Functional Food

“Let food be thy medicine and medicine be thy food”

— Hippocrates

For the past year we have been talking about how to boost the immune system with plant phytonutrients and how this can present new opportunities for farmers, particularly if plant pharmaceuticals can be extracted from plants grown in a controlled environment. 

With an increased knowledge of downstream processing, farmers could learn to take advantage of plant pharmaceutical power quickly and naturally and boost their market share.

More than half our medicines come from plants

If more than half of our drugs originated from plants, it should be possible to select which plants display bioactivity using artificial intelligence and machine learning to extract bioactive molecules and reduce the time to create natural plant based drugs. This is already happening with high throughput screening of secondary metabolites from plants. Alternatively farmers can use this knowledge to market the whole plant entourage effects which lead to positive health benefits.

As we begin to understand more about disease pathways there is mounting evidence that plant phytonutrients may unlock new applications through a better understanding of molecular biology and clinical trials. Examples of this include new applications for forskolin from Coleus forskohlii and phytochemicals from Stephania Glabra, which are being rediscovered as adenylate cyclase and nitric oxide activators, potentially opening new ways to treat obesity and atherosclerosis.

To Know The Future We Have to Understand The Past

Taxol is now synthesized from liquid plant cultures as direct extraction poses an ecological threat to the Yew tree. Paclitaxel works by inhibiting tubulin inside cells which is essential to cell division and prevents rapidly dividing cells growing thereby slowing cancer growth. New ways to cultivate these plants using controlled environmental agriculture could conserve our native species whilst harnessing their pharmaceutical power.

Both Vincristine and Vinblastine extracted from the Madagascar Periwinkle (Catharanthus roseus) are commonly used in treatment of acute lymphoblastic leukaemia and Hodgkin’s Lymphoma. Vinca periwinkle grows very easily in plant tissue culture and with hydroponics it can be controlled to grow under different light spectrums. Like Paclitaxel these alkaloids work by preventing cells from dividing by blocking tubulin in cancer cells. This also affects healthy rapidly dividing cells at the same time which is why hair loss occurs during chemotherapy. 

The quest for new antimalarial compounds remains strong as it is one of the deadliest diseases in the developing world. So the discovery of Artemisinin from Artemisia annua L. to combat multi drug resistant malaria was awarded the Nobel prize  for medicine in 2015. It works by killing the malaria parasite Plasmodium falciparum by indiscriminately binding to proteins in many of the organism’s key biochemical pathways.

There are challenges however as another close genus of wormwood  (Artemisia Absinthium L.) contains high levels of the toxic phytochemical thujane. Distilling the herb in alcohol increases the thujone concentration,  which is why the alcohol beverage Absinthe was banned in the US. 

Medicinal extracts of wormwood have not been shown to cause seizure or other adverse effects at usual doses. This shows the importance of validation through scientific processes to ensure plant phytonutrients have a high safety profile for human use.

During the last decade a few new plant derived drugs have been launched including Arteether, an endoperoxide sesquiterpene lactone derived from Artemisinin. 

Recent research at the Max Planck Institute suggests a role for Artemisinin in the treatment of SARS-CoV-2. Wormwood is initiated easily in tissue culture to produce clean clones and grows easily and quickly in aeroponics. 

Medicinal cannabis (Cannabis sativa) is used for neurological disorders including Multiple Sclerosis, Autism, Parkinson’s, Alzheimer’s, Tourette’s, Huntington’s and also for Neuropathic pain and Epilepsy since legalisation began across the States. Benefits for chemotherapy induced nausea, glaucoma, appetite stimulation, cancer pain, inflammatory conditions and asthma have also been reported. 

Approval was granted in 2018 for Epidiolex (Cannabidiol), the first plant derived Cannabis drug to be approved by the US FDA for use in severe refractory Epilepsy. It is important to reiterate that science needs to validate physiological health benefits due to cannabis related effects within clinical trials since long term negative side effects are possible.

Not all our plant drugs came from the Amazon and in 1775, Dr William Withering who studied medicine at Edinburgh University discovered an alternative treatment for heart problems when one of his patients used a local gypsy herbal remedy from Foxglove (Digitalis purpurea) and promptly improved his condition. 

Digitalis sometimes called ‘dead man’s bells’ contains the glycoside digoxin which works by slowing the heart rate and increasing the intensity of the muscle contraction so only minute doses are required daily to be effective in treating cardiac arrhythmia. 

Poppy (Papaver somniferum) contains the active opiate morphine (named after the Greek god of dreams, Morpheus) used for pain relief during trauma and as the traditional ‘end of life’ drug to ease suffering. The earliest images of opium poppies were found in ancient Sumerian artefacts (dating around 4000 BC), later named by ancient Greeks who called it Opion, eventually leading to its modern name Opium. The active opiate ingredient of the opium poppy morphine is collected by extracting the fleshy seed pod. An opioid attaches to the receptors found in the brain, gastrointestinal tract and spinal cord to reduce the transmission of pain messages to the brain.

Opiates are used in UK medicine as strong painkillers but are prescribed with care due to the addictive nature of the drug. The first commercially pure product introduced for therapeutic use was morphine marketed by Merck in 1826.

Quinine (Qualaquin) is an alkaloid from the Cinchona Calisaysa tree that grows in South America forests used for centuries in the prevention and therapy of Malaria. It was a popular herb used by the Quecha tribes of the Amazon rainforest. Modern research has shown it to also be a very effective treatment for fevers, cold and influenza although side effects are common with permanent kidney damage a concern.

Hypericin, an anthraquinone from  St. John’s wort (Hypericum perforatum) has received much attention for use as an antidepressant.

Rauwolfia Serpentina commonly called Indian Snakeroot contains the extract reserpine which depletes adrenergic neurotransmitters and remains an effective treatment for hypertension today. 

The key chemical component of Salix (Willow) Salicylic acid, was first described by Hippocrates who referred to a white powder derived from willow bark used for pain relief, fever and for anti-blood clotting.  In 1763, chemist Edward Stone isolated the active ingredient and it has since been used in medicine both for analgesic and anti-clotting properties. The first semi-synthetic pure drug aspirin, based on a natural product salicin isolated from Salix alba, was introduced by Bayer in 1899. Aspirin is now synthetically created through a chemical reaction between salicylic acid and acetic acid. Americans consume around 16000 tonnes of Aspirin every year due to its wide ranging medicinal properties. These include pain relief, reduction in cerebral thrombosis and a reduction in rheumatoid arthritis as scientists discovered it prevents the growth of cells that cause inflammation. 

Willow bark often turns up as a natural alternative to salicylic acid, because it contains salicin. When orally ingested, salicin is converted into salicylic acid by specialized enzymes in our digestive system. Willow bark (white or black) sold as a dietary supplement, herbal tea, or topical ointment, is known as ‘liu shu pi’ in traditional Chinese medicine. 

Will we grow our medicines in CEA in the future? 

From the Amazon rainforests to the coral reefs of the Caribbean, scientists search for cures to both old and new diseases. Bioprospecting is labor intensive and only one in thousands of compounds tested may demonstrate pharmaceutical promise. Despite this we know half of all human pharmaceuticals now in clinical use were derived from plant based natural sources. 

Nature may hold the key to finding the cure for emergent diseases, not least for new Coronaviruses. With hundreds of Coronaviruses discovered, only a few have become so virulent to cause epidemics and of course Covid-19, the cause of the current pandemic. It is possible that many pathways may be disrupted by bioactive chemicals in plants. For example, Wasabi Japonica displays anti-thrombotic effects which could have applications to treat blood clots in patients with SARS-CoV-2.

Pushing the boundaries of controlled lighting to make these plants produce stable disease fighting nutraceuticals

Plant factories with artificial lighting (PFAL) can aid steady production of high quality medicinal plants all year round by artificially controlling the environment (light, temperature, humidity and fertilizer) and allow growers to plan their production. This is best observed in Japanese PFALs, leading the world in terms of CEA to produce plants with a range of attributes that aid human health. For instance growing under controlled environment conditions may increase anthocyanin concentrations to enhance uniform metabolites with clean precision production.

While we don’t anticipate it is economically viable to grow many of these traditional medicines in hydroponics, there is no doubt they could be adapted for new purposes of extraction. With a combined approach of plant identification, controlled growing and research of the entourage effect and combined efficacy against disease we believe these tools can aid future discoveries. To do this we need production of clean virus free clones grown in plant tissue culture and acclimated in controlled environments. This enables us to keep production uniform and close to extraction facilities. We encourage you to reach out if you are interested in our approach to grow some of these unique medicinal plants as we have many years experience in controlled environment trials.

Janet Colston PhD is pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

You can follow The Functional Plant Company on Instagram. 

Covid-19 effects are the most well known in the world. More than a year on from the start of the pandemic and despite the roll out of effective vaccines in richer countries we still have a limited drug arsenal with worldwide coverage to make life easier for those most at risk. According to physicians at the Mayo clinic, the FDA have approved the antiviral drug Remdesivir and emergency use of the anti-inflammatory drug Baricitinib for use in patients hospitalised with COVID-19. In the UK Dexamethasone, an anti-inflammatory corticosteroids is authorised for use in severe cases. Studies found this drug reduces the risk of death by about 30% for people on ventilators and by 20% for people who need supplemental oxygen. But Dexamethasone and other corticosteroids may actually be harmful if given for less severe COVID-19 infections so it is reserved only for the critically ill. Clinical studies in the UK this year showed an additional benefit from the combination of two drugs used for rheumatoid arthritis, Tocilizumab and Sarilumab, which reduced the risk of mortality in ICU patients by 24%.  

Researchers across the world are examining the effects of anti-inflammatory drugs and other immunotherapies to suppress the virus. Controversial anti-malarial drugs were initially thought to control the virus but were quickly withdrawn by the FDA when data analysis showed that Hydroxychloroquine and Chloroquine were NOT effective for treating COVID-19 and can lead to serious heart problems. 

Model created by Annabel Slater, working with the MRC-University of Glasgow Centre for Virus Research.

While the vaccines roll out across the world there is still the threat of COVID-19 variants lurking and developing in populations especially those geographies that have been unable to contain the virus. We now have increasing numbers of mutated spike protein variants of Covid-19 including the English Kent ( B117), South African (501.V2), Brazilian (B.1.1.248), Japan (P.1) and the Delta variant (B.1.617.2) causing concern as the virus continues to mutate and becomes more transmissible. This means we cannot be complacent and must keep searching for new ways to combat the disease whether through alterations of the vaccine or development of new drugs to reduce viral load. Of course this must be in tandem with continued social distancing, testing and isolation compliance with local laws to reduce the spread.

Epidemiologists writing in the journal Nature suggest Coronavirus is going to stay with us for some time. Then there’s the effect it leaves behind on our bodies, a new disease called Long Covid or as some in the US are calling it Long Haul Covid. Long covid is now defined by time post infection and acute long covid lasts 3 weeks whereas chronic long covid is ongoing for more than 12 weeks. The effects of long covid are wide ranging with some not even aware they have it, and symptoms include diarrhoea, nausea, vomiting and gastrointestinal pain. For those that recover from serious illness the effects can be life changing and far reaching including muscle loss, organ failure, reduced lung capacity, brain fog and even depression. 

Researchers are still learning how an infection with SARS-CoV-2 affects different parts of the body so new medicines can be developed. Although there is hope on the horizon with new antiviral drugs like TEMPOL and others in development we must remember the pathways of this disease are complex and still emerging. 

With this backdrop in mind we hope medicinal plant derived products that selectively block the ACE2 receptor may provide alternative ways to treat SARS-CoV-2. This blog is designed to be of interest to people with an interest in foods that can have a medicinal effect, growers who aim to produce unique medicinal crops and for scientists interested in the pharmaceutical properties of plants. 

Mechanism of cell entry and replication causing inflammation

We need to understand how the virus affects our bodies to know how to prevent dangerous physiological changes. Studies show the SARS-CoV-2 virus enters via epithelial and endothelial cells on the inner surface of blood vessels (see this 3D model of a blood vessel, spin it around as see the endothelial cells in purple on the inner wall) of both the large and small intestine and the respiratory tract using the angiotensin-converting enzyme 2 (ACE-2) as a binding protein. ACE-2 is embedded in cellular membranes and expressed in several critical tissues, including alveolar lung cells, gastrointestinal tissue and throughout the central nervous system. ACE-2 is important as it acts as a potent negative regulator of the renin angiotensin system (RAS) which controls blood pressure. Dr Craig Daly a vascular scientist from the University of Glasgow talks us through an easy to follow tutorial of the RAS pathway critical for maintaining homeostasis and controlling levels of the hormone angiotensin, which in turn controls blood pressure via constriction and dilation of blood vessels. 

When we are infected with coronavirus, the spike protein on the virus surface binds to ACE-2. Like a key in a lock the cell responds and encapsulates the virus pulling it inside to replicate its ribonucleic acid (RNA), creating a blueprint to potentially make 10-100 of virions that are subsequently released back into the bloodstream ready to infect more cells. 

After SARS-CoV-2 particles leave infected cells, there is a sudden release of inflammatory cytokines which results in leaking of fluid into alveolar sacs in the lungs. This is the ‘cytokine storm’ we hear so much about and this can be devastating if the viral load is too high as we have seen in healthcare workers at the beginning of the pandemic who were poorly equipped with PPE. Systemic inflammatory responses and multiple organ failure tragically cost the life of Dr Li in Wuhan in 2019, the medic who broke the news to the world. As we discovered in the early days, the lungs are unable to remove harmful gases like carbon dioxide and they cannot efficiently provide oxygen to the body. This helps the virus multiply rapidly in the lungs resulting in Acute respiratory distress syndrome. 

While respiratory symptoms are the most common sign of the disease, a recent review suggests 53% of people hospitalized with COVID-19 experience at least one gastrointestinal (GI) symptom during their illness. There is evidence that encountering GI symptoms with COVID-19, or developing them alongside underlying GI conditions like cardiovascular disease or diabetes can also increase the risk of disease severity. More recent research shows that the virus may alter the gut microbiota contributing to nausea and diarrhea. So all those memes of toilet roll are valid! The virus is then free to infect other targets like the central nervous system to cause further damage linked to neurological diseases resulting in long-lasting brain fog.

What natural plant extracts could potentiate some of these pathways?

Much of the latest research on plants used to fight covid symptoms and its after-effects originate from work in Asia and Thailand. It should be remembered that these plants need to be tested together and trials should be properly controlled as some extracts taken in excess or together can have detrimental outcomes. For instance peppermint and black teas can inhibit the absorption of iron, important in the transfer of oxygen to our tissues. So as we propose potential plants that exhibit beneficial effects at the sites of SARS-CoV-2 entry or may provide some inhibitory effects, it should be taken with a degree of optimistic caution in what may provide an alternative to pharmaceutical drugs. 

Physiological effects and mechanisms worth tackling with alternative plant based therapies:

1. Fever control 
2. Calming the cytokine storm 
3. Prevention of viral shedding 
4. Plants that control blood pressure through Angiotensin II or ACE
5. Antagonising the SARs-CoV-2 spike protein
6. Prevention of platelet aggregation
7. Plant based nutrient balance of the renin angiotensin system
8. Boosting the gut microbiome
9. Antifungal activity to combat mucormycosis
10. Diabetes regulation with plant phytonutrients from our previous article 
11. Downstream brain fog with plant phytonutrients from our previous article 

Many plants display antiviral activity and we examine if these theoretically can provide a ‘super tea’ or emollient to reduce symptoms and help people recover from covid infections. Here we describe a few selected plants that are involved in trials (there are too many to provide a complete list but if you are interested reach out and we can discuss further) that could contribute to recovery from Coronavirus highlighting specific traits that potentiate the viral pathway. 

1. Plants that control fever

Andrographis paniculata has been used for hundreds of years in oriental and Ayurvedic medicine for a number of different ailments. The genus Andrographis belongs to the Acanthaceae family made up of around 40 different species. The plant is reported to possess wide ranging immunological, anti-bacterial, anti-inflammatory, anti-thrombotic and hepatoprotective properties. Phytochemical studies reveal a diverse range of compounds including diterpenoids like andrographolide, neoandrographolide and dehydroandrographolide. In India it is known as the Indian Echinacea where the aerial parts of the plant (leaves and stems) are still used in herbal medicines for flu and colds. It is also currently being used in Thailand for COVID-19 treatment of mild and moderate disease. Researchers purified the compound andrographolide which showed 99.9% inhibitory activity against the virus in cell cultures in the lab. 

Eucalyptus – alongside Frankincense and Lavender oils, Eucalyptus is classed as an essential oil that helps reduce significant fever. In the late 1800s, the ability to promote sweating and clear mucus led to eucalyptus oil being prescribed for respiratory conditions including bronchitis, flu, asthma, and coughs acting as a decongestant. Eucalyptus globulus leaves are distilled to extract the active oil Eucalyptol. But remember it is only recommended for topical application and must be diluted in a carrier oil like olive oil or it may burn or irritate the skin.

Eucalyptus in tissue culture from callus

Indian Frankincense comes from the Boswellia serrata tree, which is native to India, North Africa, and the Middle East. Farmers tap the tree to collect its resin. Boswellia resin and its active ingredient, boswellic acid, appear to have a good anti-inflammatory effect on the body according to a review article suggesting it has good antipyretic (reduces fever) activity.

Japanese Honeysuckle is traditionally used for fever, sore throat, colds, flu and some infectious skin diseases. It is part of a combination of herbs called Yin Qiao San that was composed in the 18th Century when trade with the West brought new epidemic diseases to China. In China Qiao San was given to people with the initial symptoms of COVID-19 infection. 

In a 2018 review of the biological properties of honeysuckle, several studies demonstrated significant anti-bacterial, anti-viral, anti-inflammatory and antipyretic effects. Japanese honeysuckle was subsequently used in combination with other herbs and given to front line medical staff treating SARS in Beijing, none of which contracted SARS. Many Chinese provinces have issued preventative programmes using herbal medicines against COVID-19, and a review of the evidence suggests that people at high risk would probably benefit from taking CHM (Chinese Herbal Medicine) formula for prevention. This is now readily available in all Chinese  hospitals and pharmacies.

Hibiscus Among the medicinally active species is Hibiscus sabdariffa, the flowers of which are rich in phytonutrients and antioxidants like Vitamin C. One of the safest species for nutraceutical consumption, the hibiscus plant is made up of many plant acids, including citric acid, malic acid, tartaric acid and hibiscus acid which is unique to hibiscus.

There are many bioactive chemical constituents in Hibiscus including alkaloids, anthocyanins, and quercetin. With its high antioxidant levels, hibiscus reduces low-grade systemic inflammation when the lymphatic system is congested. Extracts of Hibiscus sabdariffa calyx were shown to have significant antipyretic activity in lab tests on fever induced in rats via a mechanism distinct from that of Aspirin. 

Extensive antihypertensive effects of Hibiscus have been widely reported and calyx extracts operate via vasorelaxant pathways of both endothelial cells and vascular smooth muscle cells, mediated through an increased production of nitric oxide.

2. Plants that calm the cytokine storm

Almost all plants will display some anti-inflammatory activity but here we pick out a few that have been studied extensively in peer reviewed journals and have relevance to COVID-19. 

Ashwagandha (Withania somnifera) also known as Indian Ginseng

Two independent research groups have discovered that Withaferin A (WFA), a steroidal lactone with anti-inflammatory and anti-tumorigenic properties, may bind to the viral spike protein of SARS-CoV-2 thereby blocking or reducing interactions with the host ACE2 receptor. WFA is also capable of reducing the secretion of various proinflammatory cytokines. One group has shown WFA does not alter expression of ACE2 in the lungs of tumor-bearing female mice. This is important as downregulation of ACE2 has recently been demonstrated to increase the severity of COVID-19 resulting from increased circulatory Angiotensin II levels through ACE (remember from the video tutorial this hormone increases blood pressure). So if  WFA does not downregulate ACE2 it has real potential as a therapeutic agent to treat or prevent the spread of COVID-19.

At least three independent research groups have suggested that phytochemicals found in Ashwagandha could be developed as a therapeutic agent against COVID-19 infection using molecular docking approaches.

Ashwagandha is from the solanacea family, related to tomatoes, eggplant and peppers. Unlike these relatives, there is no definitive evidence the fruiting berries are edible as they act as a strong emetic  (although temptingly beautiful above) and like ginseng it is the root after several years of growth that is valued most for powdered and gummy herbal remedies. It is NOT advised for pregnant and nursing women.

Sweet Wormwood (Artemisia Annua) grown from seed clean in tissue culture and then in  Aeroponics 

Researchers in the US have shown that extracts of Artemisia Annua with active compound Artemisinin, commonly known for its use as an anti malaria drug also has the ability to inhibit the replication of SARS-CoV-2. Both A. Annua and Artemisinin have been shown to reduce levels of the inflammatory cytokines interleukin-6 and tumor necrosis factor-alpha in vivo. Early results suggest the active component in the extracts is likely something besides Artemisinin or is a combination of components acting synergistically to block post-entry viral infection. This area of research remains one of the most positive for fighting coronavirus cytokine effects. 

3. Plants that act as detergents preventing Viral shedding 

Butterfly Pea (Clitoria ternatea) is a holy flower in India used in daily puja rituals. The leaves are high in saponins known to act as a detergent which might be useful in removing the spike protein of Coronavirus. It may play an active role in viral shedding as the plant has been identified as a metalloproteinase inhibitor which could disrupt the process reducing the formation of virus. The metalloproteinase, ADAM17 involved in ACE shedding can be targeted using plants like Butterfly Pea as bio based surfactants. It has also been widely used in traditional medicines, and as a supplement to enhance cognitive functions and alleviate symptoms of numerous ailments including fever, inflammation, pain, and diabetes. Although the flower is widely used in teas and colour changing gins, both the seed and roots are not recommended (you can actually be fined in Taiwan for selling it as a foodstuff, butterfly pea is only used for minimal dye levels) as a food source due to much higher levels of saponins. It could however be highly useful as a natural soap based disinfectant in the fight against COVID-19.

4. Plants that control blood pressure through Angiotensin II and ACE

Various medicinal plants have shown inhibitory effects against Angiotensin II, many of which control blood pressure through this mechanism. Our previous EAT THIS blogs describe the actions of many plant based phytonutrients that have actions to reduce blood pressure. 

Coriander (Coriandrum sativum cilantro)

Coriander (Coriandrum sativum L.) was a traditional medicine for the treatment of cardiovascular and gastrointestinal diseases. Widely used by the Egyptians, coriander seeds were found alongside possessions of Tutankhamen when the tomb was excavated from the Valley of the Kings. It was a herb recommended by Hippocrates to treat inflammatory diseases and reduce blood pressure. In a 2013 study coriander oil was found to have strong potential as an ACE inhibitor. A few years later, 16 bioactive compounds extracted from coriander leaves were shown to exhibit significant ACE inhibition. Coriander and chlorella combined can remove heavy metals like mercury in the body in just a few months which helps people lose weight as it stimulates the pancreas to secrete insulin and lower blood sugar levels (reducing the risk category for serious COVID-19 illness). After some early concerns a study published by the British Heart Foundation has shown it is safe to use ACE inhibitors and Angiotensin receptor blockers to control blood pressure. 

Pomegranate (Punicagranatum Cassia) In Ancient Greece pomegranate represented fertility, eternity and good fortune and Hippocrates referred to its many medicinal properties including dampening inflammation and detoxifying. More recently pomegranate juice has been shown to have a competitive mode of action against coronavirus. Just a small cup of pomegranate juice can reduce ACE activity by 36% and lower systolic blood pressure by 5%. 

Pomegranate trees grown in Archangelos, Rhodes – medicine in your own backyard just as the Ancient Greeks would have done. Dr Li, a world renowned physician and scientist, describes how pomegranate promotes good bacteria in the gut, decreasing inflammation and lowering blood glucose levels. 

Pomegranate can be grown from seed in tissue culture to produce healthy clones. Dwarf varieties have potential for greenhouse production similar to blueberries. 

Holy Basil (Ocimum Sanctum) also known as Tulsi has been known to target the reverse transcriptase activity of HIV and theoretically could reduce activity of SARS-CoV-2. The leaves (main photo) contain Eugenol which is an effective treatment for high blood pressure. Just 100g of Basil provides 105% of Vitamin A and 30% of Vitamin C daily requirements. 

Garlic (Allium Sativum)

Anecdotal evidence from our Garlic blog just over a year ago suggests many people found the remedy to alleviate symptoms of covid. Garlic organosulfur compounds, allicin have many medicinal properties that could alleviate Covid 19 symptoms and evidence suggests it can not only  target the viral replication of SARS-CoV-2 but also inhibit ACE activity to dampen Ang II-induced vasoconstrictor responses in blood vessels.

Galangal  (Boesenbergia rotunda) High throughput fluorescence screening of plants in a trial in Thailand has picked up activity of a phytonutrient in galangal called Panduratin A acting as an anti-SARS-CoV-2 agent preventing entry to human airway epithelial cells in the lab. The Nature article concludes the purified compound, Panduratin A has a potent inhibitory effect against SARS-CoV-2 replication and infectivity with the favorable cytotoxicity profile. Interestingly, panduratin A inhibited SARS-CoV-2 infectivity and replication at both pre-entry and post-infection phases, and its antiviral activity was even more potent than hydroxychloroquine. Related to the ginger and turmeric zingiberaceae family this shows promising therapeutic value in the fight against Coronavirus. Studies of curcumin on antiviral activity also show promise. See our previous articles on growing these plants in a controlled environment.

5. Antagonising the spike protein

A study last year found that curcumin, nimbin, withaferin A, piperine, mangiferin, thebaine, berberine, and andrographolide have significant binding affinity towards spike glycoprotein of SARS-CoV-2 suggesting they could provide a route to prevent cellular infection. 

Neem (Azadirachta Indica) Nimbin extract from Neem is known for its antibacterial properties but molecular docking studies have also proved extracts could have inhibitory activity on the Papain like protease of SARS-CoV-2. Neem extracts have been well documented including inhibitory action against viral activity of herpes, smallpox, chickenpox, HIV.

Self heal (Prunella vulgaris) in Tissue Culture

Researchers in Canada have shown mutations in the SARS-CoV-2 spike protein increases its incorporation into cells leading to increased viral load causing significantly higher transmission rate in infected individuals, but thankfully there has been no reported significant change in disease severity. Self heal contains a compound, suramin, which displays potent inhibitory effects on the spike glycoprotein in an in vitro model cell system. This could prove to be a crucial breakthrough against variants that are more infectious, particularly if these compounds can be manufactured as a nasal spray. 

Licorice (Glycyrrhiza glabra L.) Licorice is a plant of the climbing  pea family containing the natural sweetener glycyrrhizin in the root which is over 50 times sweeter than sucrose. Scientists have known for some time that glycyrrhizin improves defences against viral infections, particularly rotavirus which invades the intestines leading to diarrhoea. Indeed glycyrrhizin increases the body’s ability to shed rotavirus by 50% in the lab, a process thought to operate through recruitment of T cells which help reduce infection. A German group demonstrated that glycyrrhizin, the primary active ingredient of the licorice root, potently neutralizes SARS-CoV-2 by inhibiting the main viral protease. These experiments highlight glycyrrhizin as a potential antiviral compound that should be further investigated for the treatment of COVID-19. 

Licorice prefers its roots to be wet and researchers at Chiba university in Japan developed a pressurised hydroponic system to produce reliable root mass in half the time it would take to grow wild. But you should consume Licorice in moderation as it can interfere with sodium and potassium levels which can lead to increased blood pressure. A Licorice tea every few days is ideal. 

Licorice in tissue culture

6. Plants that inhibit platelet aggregation

SARS-CoV-2 and its spike protein directly stimulate platelets to facilitate the release of coagulation factors, the secretion of inflammatory factors, and the formation of leukocyte–platelet aggregates. Although platelet activation is critical for thrombosis and is responsible for the thrombotic events and cardiovascular complications, the role of platelets in the pathogenesis of COVID-19 remains unclear. Critically ill patients diagnosed with COVID-19 may develop a prothrombotic state that places them at a dramatically increased lethal risk so it is important to find ways to inhibit the process. 

Wasabi Japonica is prone to many diseases but clean stock plants can be initiated in tissue culture by ‘The Functional Plant Company’.

Platelet aggregation was first associated with COVID-19 in patients in Wuhan, China as infection produces a prominent elevation of fibrinogen and D-dimer/fibrin degradation products. The damage is caused by the immune system going on the attack (cytokine storm), damaging blood vessel walls and removing several of the normal anti-clotting mechanisms. Essentially the virus causes damage to the lining of blood vessel walls increasing systemic hypercoagulability and blood clots are more likely to form. The degree of D-dimer elevation positively correlates with mortality in COVID-19 patients.  

We have previously described the wide range of medicinal properties, anti-microbial, anti-diabetic, anti-asthmatic, anti-cancer, antiviral and anti-fungal in Wasabi Japonica. The active glucosinolate, 6-methylsulfinylhexyl isothiocyanate (6-MSITC) found predominantly in the swollen stem or rhizome of Wasabi as a potential inhibitor of human platelet aggregation in vitro.   

Wasabi ITCs are effective agents for inflammation based on their rapid action and the low levels needed. Isothiocyanates of Wasabi and other crucifers like watercress and broccoli are anti-inflammatory and anti-asthmatic and may provide ease of SARS-CoV-2 symptoms. 

7. Plants can increase essential nutrient levels boosting immunity

Vitamins play a vital role in immune function. 

Patients with severe Covid-19 are reported to be low in both iron and Vitamin D levels and associated with severe acute respiratory disease. These groups include the elderly, people living in the northern hemisphere, obese adults and darker skinned people who produce significantly less Vitamin D and are more likely to be anaemic than other groups.

Low levels of Vitamin D3 actually inhibit renin. Less renin production tips the equilibrium in favour of more Angiotensin II, subsequently raising blood pressure.

Cholecalciferol (Vitamin D3) is a prohormone nutrient synthesised from meat retrieved cholesterol and is processed in the liver using iron as a cofactor for activation.  With increased levels of Vitamin D the expression of proinflammatory cytokines that induce production of C-reactive protein can be significantly diminished. 

There are now calls to supplement daily diets with 1000-2000IU/day Vit D3 to lessen the severity of COVID-19. Vitamin D3 is not a cure for covid-19 but it does have global significance if studies suggest 30-50% of the world’s population are deficient. A study in 2020 showed that a Vitamin D3 blood level of at least 75 nmol/L is needed for protection against COVID-19. An adult needs 4000 IU/day of Vitamin D3 for 3 months to reliably achieve a 75 nmol/L level. People with darker skin need twice as much Vitamin D3 as they produce more melanin which blocks UVB rays and inhibits production of Vitamin D. These doses can greatly reduce the risk of severe illness, but this is not enough for treatment of acute viral infection, which requires a 60,000 to 120,000 IU dose intervention.

Moringa oleifera also known as the miracle tree due to its multiple medicinal uses. It is a fast growing, drought resistant plant that reaches full maturity in less than a year and although we don’t know of anyone growing in a commercial controlled environment we believe it is theoretically possible. It is one of the most nutrient dense plants in the world containing a high abundance of vitamins. Moringa has an impressive range of anti-Inflammatory, anti-viral, anti-fungal, antidepressant activity and cardiovascular protective effects.

Vitamin A plays a vital role in strengthening the immune system, protecting us against common infections such as flu by maintaining healthy mucus linings inside the nose and the lungs. 

Moringa leaves are a fantastic source of protein and high in plant based non heme iron and antioxidants. Consuming just 10g of moringa powder a day for 3 months can significantly increase levels of iron, antioxidants and Vitamins A and C in the bloodstream. Vitamin A is normally found in dairy, eggs and oily fish but also in some leafy greens and is essential for iron metabolism. Moringa contains four times the amount of Vitamin A (also known as retinol) as carrots, the vegetable we naturally think is the best for our eyesight as it produces important pigments for eye retina health. Pregnant women should be cautious about supplemental Vitamin A and intake only through a balanced diet is recommended. 

Remember that yellow, red and green fruits and vegetables contain beta and alpha carotenoids, lutein, lycopene, zeaxanthin, astaxanthin, β-cryptoxanthin which act as a precursor to Vitamin A. 

Can a plant based diet provide an adequate source of Iron? 

We traditionally consume heme iron from meat, poultry and seafood sources whereas non-heme iron is found in plant foods like whole grains, nuts, seeds, legumes, and leafy greens. Over 79 million people around the world are vegan and don’t eat either meat or dairy products. It was always thought vegans could be deficient in iron due to low absorption of nutrients as our diets change and we move to healthier plant based diets. 

Why is this important? Well heme Iron is absorbed more easily than non heme iron and stored in the body as ferritin, it acts as a cofactor in our blood cells and essential for the uptake of oxygen. We know that SARS-CoV-2 patients have low iron levels which exacerbates oxygen levels to the lungs. 

Some eminent physicians suggest the latter plant based non heme source is adequate for all our iron requirements as we also consume more Vitamin A, C and E from plants which aids non heme iron absorption. Infact, Dr Greger presents data that shows too much heme iron cannot be processed by the body and leads to pro-inflammatory diseases like diabetes and Chronic heart disease.

Life saving high dose Vitamin C

It is becoming clear that high blood levels of not just Vitamin D3 but also Vitamin C are needed to prevent COVID-19 deaths.

Infection triggers a severe inflammatory cellular reaction in the body which results in a decrease in Vitamin C. Along the evolutionary timeline 40 million years ago we lost the ability to make Vitamin C in our bodies due to a genetic mutation.

Unlike most mammals we are unable to synthesize Vitamin C endogenously ourselves so we must access it from our diet. Vitamin C plays an important role in immune function and improves the absorption of nonheme iron, the form of iron present in plant-based foods. It is well understood that insufficient Vitamin C causes scurvy, which is characterized by fatigue. We all know that sailors used a variety of citrus fruits to prevent scurvy but in Scotland where citrus fruits were not abundant they foraged Rock Samphire on the west coast as they found the leaves were high in Vitamin C. Today Rock Samphire is located in only a few inaccessible cliffs but it has potential as a CEA crop.

Rock Samphire – Sea Fennel in tissue Culture 

The plant is not well used in herbal medicine as it can be so hard to access but if you can find it then it’s very useful as a herbal tea. It contains Vitamin C (ascorbic acid and dehydroascorbic acid), polyacetylenes (falcarinol and falcarindiol), flavonoids (diosmin), furanocoumarins, pectin, and minerals. Falcarinon, acts as a natural antibiotic and has a positive effect on the digestive tract. 

Kumquat Yuzu (hybrid)

Hesperidin and ascorbic acid in Yuzu counteract the cell damaging effects of the oxygen free radicals triggered by viral infections and inflammation. There is discussion about the preventive efficacy of Vitamin C, at the dose achievable by the diet, as recent reviews suggest it can be useful in the case of strong immune system burden caused by viral disease. 

Today we can access many exotic dried fruits from around the world that are high in Vitamin C including Acerola, Schisandra and Goji berries. Read more about them in our previous EAT THIS articles. Just keep eating those berries! 

8. Plants that boost the gut microbiome 

Associations between gut microbiota composition, levels of cytokines and inflammatory markers in patients with COVID-19 suggest that the gut microbiome is involved in the magnitude of COVID-19 severity possibly via modulating host immune responses. This change in gut microbiota dysbiosis post disease could contribute to Long haul covid, highlighting a need to understand how gut microorganisms are involved in inflammation and COVID-19. I have picked out two I grow in controlled environments but there are many fruits and vegetables that act as probiotics (boost gut commensal bacteria) and prebiotic (feed the bacteria).

Chinese Yam

Chinese yam or air potato increases beneficial Lactobacillus bacteria which is thought to be disrupted following SARS-CoV-2 infection. However, Chinese yam is an invasive species in the United States. Multiple states, including Michigan, have active control programs whereby the government asks citizens to report sightings of Chinese yam. As with water yam, Chinese yam grows well in aeroponic CEA reducing the risk where they can be monitored and controlled. 

Kiwi in Tissue Culture, dwarf varieties in CEA have potential 

Kiwifruit affects intestinal microbiota populations, namely Lactobacillus, Bacteroides, Clostridium, Bifidobacterium, and Enterococcus. Studies have shown Kiwifruit is a prebiotic selectively enhancing the growth of intestinal lactic acid bacteria, promoting the content of faecal lactobacilli and bifidobacteria. Since 2015 there has been a shift towards growing kiwifruit in New Zealand in high poly tunnels with drip irrigation to protect them from disease.  It is not just the human population that is suffering from increased viral infections, many intensively farmed crops also have viral threats. 

A meta-analysis (data gathered across many clinical studies) in 2020 found that more than half of Covid-19 patients had received antibiotics despite only 7% presenting with a bacterial infection. It suggests the use of antibiotics may accelerate the damage to anti-inflammatory promoting bacteria in the gut. The probiotic effect of kiwifruit is transient so you must keep eating those juicy fruits.

9. Antifungal activity to combat mucormycosis

Mucormycosis is a serious but rare fungal infection caused by a group of molds called mucormycetes that commonly affects the sinuses or the lungs after inhaling fungal spores from the air. It is caused by exposure to mucor mould which is commonly found in soil, plants, manure, and decaying fruits and vegetables. Increased occurrence of mucormycosis in COVID-19 patients in India is being reported. They require antifungal treatments including liposomal amphotericin B injections but these may lead to side effects. There are many plants with antifungal properties, in fact most of those we describe in this article will have potency against fungal spores. The most accessible include garlic, turmeric and ginger but they should be taken as supplements if fungal disease is suspected. 

Unexpected positive side effects of Covid

Forbes reported on a case in the U.K. of a 61 year old man with aggressive non hodgkin’s Lymphoma going into full remission after contracting COVID-19. While this is an isolated case it gives huge insight into the mechanisms of blood cancer processes and a future opportunity of study. This will undoubtedly lead to understanding new mechanisms linked to cytokine release and the body’s own immune reactions. 

The molecular mechanism by which these medicinal plants target influenza virus can be studied to understand if they attack any molecules overlapping between SARS-CoV-2 and the Influenza viruses. Himalayan forests are abundantly rich in medicinal plant species and a study has documented the presence of ethnomedicinal plants against bronchitis caused by influenza virus, rhinovirus, adenovirus, coronavirus and respiratory syncytial virus.

With emerging Coronavirus variants, there is concern they cannot be quickly and efficiently eliminated in populations across the world leaving us all vulnerable to future pandemics,  or more likely localised epidemics. Regardless, we should be ready and working towards multiple strategies to combat outbreaks and plant biochemistry can play a part if we have peer reviewed studies initiated now. 

Growing plants in Controlled Environment Agriculture

Many if not all these plants can be grown in some form of controlled environment whether it be hydroponics or initiated as clean clones using plant micropropagation. Adapting farms to grow medicinal plants is not difficult and most of these plants will grow in a pH range 6-6.5 with EC 1-1.5 and suitable substrates. The question remains if there is an outlet for this kind of opportunity. That is up to our readers, farmers, growers and academics to address. We have previously discussed many plants that contain phytonutrients and how these can be manipulated using tailored light spectrum and intensity in a clean controlled space which is essential if these plants are to be scaled up for industrial extraction. Consumers should be reassured by these plants being grown in a pesticide and fungicide free environment.  

SUPER TEAS and DETERGENTS – Natural Remedy. 

To summarise, the plants we have selected have the potential to make a ‘super tea’ with active ingredients including isothiocyanate (Wasabi), glycyrrhizin (licorice), quercetin (Hibiscus), eugenol (Holy Basil) suramin (Self heal), hesperidin (Yuzu), ascorbic acid (Samphire), artemisinin-purified and approved (Sweet Wormwood), curcumin (turmeric), withaferin A (Ashwagandha), piperine (black pepper), mangiferin (honeybush), thebaine (poppy), berberine (European barberry, goldenseal, goldthread, greater celandine, Oregon grape, phellodendron and tree turmeric), panduratin A (Galangal), allicin (garlic) and andrographolide (Andrographis). Clear evidence of supplemental Vitamin A, C and D3 supports documented research to reduce Covid-19 disease severity. Emollients made with eucalyptus, Neem, lavender, and frankincense along with nasal sprays incorporating self heal or butterfly pea soaps have potential to provide added protection against coronavirus infections. 

Having read this you may now be wondering, where do I get hold of these wonderful medicinal plants? So at this juncture I urge a little caution, many medicinal plants are available individually as dried root or tea preparations but please ensure you check they are from a reliable and validated source. Combinations can increase efficacy so check this out with your local Chinese herbalist who can advise on TCM. It is best to take professional advice before trying any plant based remedy.

We anticipate CEA farmers or even pharmacologists will want to grow these plants in the future.  If you have an interest in this we would love to engage with you as we have experience of growing a wide range of plants in a controlled environment to produce the highest quality for either study or scaling. Please reach out and consider working with us. 

I am indebted to my friend and colleague UAN & Hort America’s founder and owner Chris Higgins. Without his knowledge, support and encouragement, my entrepreneurial work would not be possible. I am grateful to my friends, physician Dr Barbara Scott MD, Veterinary Lecturer Dr Sally Anne Argyle MRCVS, cardiovascular scientist Dr Craig Daly SFHEA, and Jenny Sim LLP, for their time in reviewing this article. Hort Americas has a full resource and knowledge bank to get you set up growing any of these plants in a controlled environment. 

Disclaimer: We are not advocating this information in preference to medical advice, remember if you have serious illness and symptoms of Coronavirus or Long Covid please seek advice from your general practitioner. Our blogs are designed for people looking for advice on plants that have additional phytonutrients that can help repair the body and boost the immune system. We advise you to stay within peer reviewed research and CDC guidance. 

Unless otherwise stated all images are from plants grown using TC or in CEA by The Functional Plant Company in Scotland and images are the property of Urban Ag News. You can follow The Functional Plant Company on Instagram.The authors declare no affiliation to any companies offering herbal remedies and the information provided is a scientific peer reviewed compilation of plants that provide an opinion of the best potential inhibition of critical pathways involved in SARS-CoV-2 infections. 

Janet Colston PhD is a pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

A diagnosis of diabetes is a time in your life when you may reflect on bad eating habits. Many of us do not understand the mechanisms of disease until we are directly affected but there are some things we can do to reverse the situation.

Diabetes is a worldwide socio-health emergency caused by changes to our diets and a more sedentary lifestyle. Around 350 million people across the world are estimated to be diabetic and this is expected to more than double by 2045. 

The CDC reported Type II diabetes affects 1 in 10 Americans, that’s around 34 million people. A further 1 in 3 have signs of prediabetes, but estimates suggest up to 84% of the US population are asymptomatic and completely unaware they are insulin resistant. These are poor statistics in comparison to the rest of the developed world; in Scotland the prevalence of Type II diabetes is around 5%. The US is second only to China and India in prevalence where 114 million Chinese people account for a third of diabetics worldwide.

Five million people die annually from diabetes related illnesses.

The pandemic has highlighted a need to act against this disease as diabetes is considered a chronic inflammatory condition that leads to increased comorbidities for those contracting SARS-CoV-2. Early studies confirm the SARS‐CoV‐2 virus attaches to angiotensin‐converting enzyme‐2 (ACE2) receptors in beta cells of the pancreas, which is thought to impair insulin secretion in response to blood glucose. Since people with Type II diabetes, prediabetes and insulin resistance have an increased risk of Vitamin D deficiency they also increase their risk of oxidative stress and immune imbalance. We will discuss this aspect of disease progression in future articles. 

A brief history of how Type II Diabetes is different from other forms of the disease 

Diabetes is a chronic disease of the pancreas that affects how we turn food into energy. When we consume food the sugars and carbohydrates are broken down into glucose. High levels of glucose are released into our bloodstream which triggers factors in our blood to release insulin from the pancreas. Insulin then extracts the glucose from our bloodstream to cross cell membranes where it is used as energy for cellular metabolism. As a highly accurate sensor of blood glucose levels, the pancreas constantly monitors and automatically adjusts to maintain a stable environment. To keep blood sugar controlled overnight, our bodies release low levels of insulin from the pancreas but when we eat there is a sudden release of insulin in response to the blood glucose rise and this can be more problematic if we overeat.

Normal blood glucose and insulin release  Adapted: Jacobs DM Care 20:1279, 1997

Type I diabetes is where the body’s own immune system attacks and destroys cells that produce insulin.

Type II diabetes is where the body cannot produce enough insulin or where the body’s cells do not react normally to insulin.

Prediabetes is when you have abnormal levels of sugars in your blood. You may be feeling fatigued, more thirsty than normal and needing to use the restroom more often. These are signs that things are not quite right. Check out the full CDC symptoms here.

A fitness trainer I met a few years ago explained why so many of us ‘sleep walk’ into this condition without even knowing it. He explained that every day we eat foods that contain glucose for energy. Throughout the day the level in our blood rises exponentially until we stop eating after our supper and levels start to plateau. If we eat too much throughout the day and particularly later in the day our bodies do not have enough time nor the ability to bring the sugar levels back to baseline. So everyday our baseline levels start slightly higher than the day before. This cumulative effect exacerbates the problem when we cannot produce enough insulin to remove glucose from our blood and our cells are damaged. When we present our symptoms to our doctor, they ask for pre and post fasting blood samples to gauge our insulin response to blood glucose.

The prevalence of both Type I and Type II diabetes is continuing to rise with the latter linked to urban lifestyles, unhealthy diets and poor levels of exercise. While Type I diabetes is a lifelong diagnosis and irreversible, Type II can in most cases be easily reversed through careful dieting and a healthy lifestyle. This is important as a diabetes can lead to chronic illness causing vascular, cardiac, neurological and renal damage with a reduced quality of life and a significant reduction in life expectancy.

How can plants be used to control blood sugar levels and reverse diabetes before it causes chronic effects? 

Diabetics were traditionally treated with medicinal herbs prior to the discovery of  insulin and manufacture of hypoglycemic drugs. Keeping blood sugar at even levels is key to deciding which foods to avoid and which to include. For instance caffeine can cause a spike in blood sugar if you consume too much coffee, tea and energy drinks.

Many plants display specific anti-glycemic activity and have the potential to be grown in a controlled environment. We now want to show how incorporating some of these plant based foods in your diet can provide cellular support to reverse inflammation and disease.

Ginger is popular in our western fusion diets and contains very low carbohydrate levels. Researchers reported that people who ate small quantities of ginger daily for 12 weeks experienced lower fasting blood sugar and reduced precursors that would otherwise lead to insulin resistance and diabetes. Probably one of the easiest to add to our diet, just a little at each meal will give huge benefits. Read our blog on tips to grow in CEA. 
Image left: New Ginger roots formed in CEA

Garlic contains more than 400 phytonutrients and many of these help prevent a wide range of health problems. Compounds including allicin, allyl propyl disulfide and S-allyl cysteine sulfoxide prevent the liver’s inactivation of insulin, so more insulin is available in the body. Like ginger, smaller daily amounts of fresh garlic can be highly effective.

Fenugreek seeds are high in soluble fibre, slowing down digestion which helps lower blood sugar levels. A teaspoon of powdered fenugreek seed helped people in India with Type II diabetes by reducing post-meal blood glucose. Separate studies found that people with mild symptoms who ate fenugreek in bread (masking the bitter taste) also lowered their blood sugar levels.

Okra is commonly used in  Ayurvedic medicine to lower blood sugar levels and some reports suggest drinking okra water in the morning on an empty stomach can improve blood sugar control.
Image right: Okra grown in the field

Berries have extensive anti-diabetic properties but a few have proven scientific evidence to back up these claims. These include caperberries, acerola, cranberries, black currants, goji berries and bilberries. Read about their health benefits and how to grow them in our previous EAT THIS blogs. 

Sweet Potato and Yacon both display anti-diabetic properties. Yacon roots contain inulin, oligosaccharides and fructooligosaccharides that pass through the human digestive tract without being absorbed. This helps to aid digestion without a corresponding spike in blood sugar. Yacon has been used to make syrups suitable for diabetic patients, and is highly valued in Japan for its anti-hyperglycemic effects. Sweet Potato also contains resistant starch that has high prebiotic functionality, associated with reduced glycemic response, lowered blood cholesterol and production of fatty acids that support diverse gut flora (also disrupted by Coronavirus). 
Image left: Yacon can be started clean in Tissue Culture

Gymnema sylvestre also called Gurmar (Hindi for ‘destroyer of sugar’) is a woody climbing shrub that comes from the forests of India and Africa. It’s been used medicinally in Ayurvedic medicine for over 2000 years. Chewing on the leaves of this plant can temporarily interfere with the ability to taste sweetness. Studies found people with high blood sugar who took gymnema leaf extract for 90 days all lowered their blood glucose levels. Gymnema also appeared to increase glycemic control in more advanced type II diabetes. The study concluded that gymnema could help prevent diabetic complications in the long term.
Image right: Gurmar grown in Tissue Culture

Panax Ginseng – Ginsenosides in Ginseng, also known as saponins or triterpenoids are thought to be responsible for Ginseng’s extensive health effects. Ginseng has been used as far back as the Song Dynasty (1078 A.D.) to cure Xiaoke (pronounced sho-ow-kay) disease which today is known as diabetes. Currently, dry ginseng root is used worldwide to treat diabetes. Although more than 150 ginsenosides have been identified, triterpene β-glycosides extracts from the roots of ginseng have been found to be the most  potent, capable of stabilizing glucose homeostasis in patients with Type II diabetes. The berries and leaves of ginseng can also lower blood glucose and decrease body weight.
Image left: Ginseng grown in Tissue Culture and Aeroponics

Artemisia Annua or Sweet Wormwood is a common herb in Africa used as a herbal tea against malaria and schistosomiasis. Artemisia herbal tea has been reported to completely reverse type II diabetes in a small number of people after only 14 days. FDA-approved artemisinins have been used for decades to treat malaria but are also known to transform glucagon-producing alpha cells in the pancreas into insulin producing cells.
Image left: Wormwood grown in CEA

Ivy Gourd is a small, green climber producing a fruit with seeds similar to cucumber and is  widely consumed in parts of India. Blood sugar levels of people who had ivy gourd for a single meal were significantly lower than those who had a placebo.

Silybum Marianum or Milk Thistle is a common weed seen as an emblem of Scotland with an interesting past association with ‘The Battle of Largs’. It is a powerful antioxidant and liver detox supplement in both animals and humans with active flavonolignans including silibin A. These phytonutrients have beneficial effects on several diabetic complications, including diabetic neuropathy, diabetic nephropathy, and non-alcoholic steatohepatitis, mainly by means of antioxidant properties.
Image right: Thistle growing wild in Scottish moorland

Stevia Rebaudiana  is a member of the Asteraceae family and native to Paraguay and Brazil but also grown in Japan and China for exports. It is used as a non-nutritive sweetener and herbal supplement, available in supermarkets as ‘Steviol’. Stevioside extracts can reduce plasma glucose levels and increase insulin production which stabilizes blood sugar levels.  Stevia leaf in powder form is a supplementary food product for diabetic patients as it increases natural sweetness and helps to rejuvenate the pancreatic glands.
Image left: Stevia flowering in Tissue Culture

Cayenne chilli Pepper consumption reduces the amount of insulin required to control blood sugar and lowers blood glucose levels. According to researchers the benefits may be even more pronounced for those with lifestyle-related diabetes. Some studies have shown capsaicin in cayenne pepper reduces the production of the hunger hormone ghrelin. This is useful knowledge for overweight people looking for a controlled diet.

Nigella sativa has been shown to significantly improve hyperglycemia and diabetes control after treatment. Consumption of Nigella seeds is consistent with a fall in fasting blood glucose, blood glucose level, glycated hemoglobin and insulin resistance and a rise in serum insulin.

Shiso Perilla Some researchers have found habitual drinking of shiso tea  can be effective in preventing the onset of diabetes and others show controlled hyperglycemia in diabetes with shiso extracts containing high rosmarinic acid levels. 

How easy are these plants to grow in hydroponics? 

Common sense tells you that most plants will grow in a controlled environment particularly if they don’t mind a water based environment. This is not in question, but growing these plants consistently in a controlled environment must make economic sense. If it does then these plants can provide a unique niche market for growers. Most including ginseng, fenugreek, ivy gourd, blueberries and peppers will require specific substrates and trials with flood and drain methods in the proposed geographical climate. Some like wormwood, perilla, stevia, ginger and turmeric have potential to thrive in aeroponics. Others like garlic, okra, sweet potato and Yacon are best in the field with automated irrigation or grown wild (Gymnema, milk thistle and nigella). Perilla, Stevia and Fenugreek have potential as microgreens. Most if not all can be initiated from tissue culture to ensure clean stock provision. 

Why use a controlled environment for some of these? 

More control over metabolites can be easily achieved. The plants are grown free from pesticides and true product provenance for farmers can be used as a unique selling point. Worldwide shortages of some of these plants give opportunities to CEA farmers who can grow under controlled conditions. If you want to know more, we have trialled some of these alternative crops in controlled environments including scale up cloning in tissue culture. Many of these new crops translate well to CEA but if you are new to Agtech the resources are all in hand for you to start with Hort America’s Mastery Series. 

Disclaimer: We are not advocating this information in preference to medical advice, remember if you have serious illness please seek advice from your general practitioner. Our blogs are designed for people looking for advice on plants that have additional phytonutrients that can help repair and replenish your body and boost the immune system. A plant based diet is safe for most people in moderation however if you have a serious illness speak to your doctor before taking any of these plants. We advise you to stay within peer reviewed research and CDC guidance. Unless otherwise stated all images are courtesy of The Functional Plant Company and property of Urban Ag News. Follow The Functional Plant Company on Instagram.

Janet Colston PhD is a pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

In 2020 we spent a lot of time reflecting on functional foods from crops that we grow in controlled environments analyzing how they benefit human health. 

In a new three part series we discuss why we should boost the immune system with functional foods to prevent disease and ask ‘Why Eat This?’.  In addition, we at Urban Ag News will also start to explore why eating this is not only good for the body, but also how it might be good for the farmer and for the planet.

New Year Resolutions 

This time of year we traditionally turn our minds to resolutions for the year ahead and health is usually top of the list. This year is no different as postponed plans from a year of lock-downs and fear from a deadly virus give us a desire more than ever to live life to the full. However many are looking for a different North Star, that of personal health and protection from not just this virus but also mutated strains in the future. So after singling out individual plants and showing you what they can do for our health, we thought the start of 2021 would be the best time to bring it all together as part of a healthy diet and a healthy planet.

Does Nature hold the key to being disease free?

The human body needs protein made up of at least 20 amino acids for almost every single metabolic action to function properly. Our bodies are capable of making 11 of those amino acids but we cannot store them so we must supplement our diets with either animal or plant based protein daily to provide sustenance and energy. Animal proteins are considered complete amino acid sources, however there is growing evidence that a well balanced plant based diet may be superior in quality. These essential elements come from our edible plants in a form that helps rejuvenate our bodies ability to repair damage. We would not put diesel in a petrol motor so why do we still expect our bodies to function with unsaturated fats, or diets laden with additives and high in sugars? Our bodies are the most sophisticated machines on earth yet we sometimes expect miracles. 

Are plant based diets the way forward?

In recent years there has been a move endorsed by celebrities towards plant based diets. You can bet those celebrities have nutritionists who help balance their diets whether it be for improved sports performance or skin routines. But how can we bring this knowledge and the health benefits to people who need it the most in an affordable accessible way?

Some argue that plants do not contain adequate levels of protein and that animal protein is essential for supplementing diets. Animal protein sources are higher in Vitamin B12, Vitamin D, omega fatty acids, heme iron and zinc. There are twenty amino acids and nine are essential amino acids, including lysine, methionine, threonine, phenylalanine, tryptophan, valine,  isoleucine,  leucine  and histidine. Of these some are thought to be less abundant in plant based diets, such as tryptophan, methionine, lysine, threonine, and isoleucine. As we know these are reduced we can look for alternatives like quinoa and soya bean or fortified foods to supplement vegan or vegetarian diets. This is a possibility the WHO explored in third world countries with fortified cereal crops. Plant research continues at pace to resolve these issues which could also see us become less reliant on animal proteins in the future reducing carbon footprints and securing future food for billions across the globe.

Which functional foods to choose

Throughout the pandemic there was a global surge towards health, causing shortages of turmeric and ginger across some continents. When the outbreak started in Wuhan, citizens boosted their immunity with traditional remedies including  garlic and ginger. These plants all display properties beneficial to human health  but will not cure or prevent the virus according to the WHO. Despite this, people still widely search the internet for a natural and accessible cure. We describe plants with  additional phytonutrients as functional foods and believe they have relevance to global health as we revealed in our journey around the world in 30 Berries stretching from the Artic Tundra to the sunny climate of Barbados. We have shown how these plants are grown in different climates, and can be enhanced by controlled environment agriculture to help access these plants in environments where you don’t expect to see them growing. Who would have thought Wasabi native to Japan would thrive in Scotland or that since the 1950s Iceland has been home to one of the biggest banana plantations in the northern hemisphere.

The functional foods we discuss and suggest ‘Eat This’ in our articles include berries, peppers,  leafy greens, tomatoes, exotic fruits, bulbs, roots and tubers. All have similar anti-inflammatory, anti-cancer and cardiovascular protection properties. Each may have a unique chemical signature but when it comes down to it they all act in very similar ways to reverse oxidative stress and neutralize free radicals thereby promoting DNA repair.  It is for this reason the AHA recommends at least 5 portions of fruit and veg a day to ensure a healthy diet. 

A word of caution – everything in moderation

We are not advocating a plant based diet over animal protein, this is a lifestyle choice. But what we aim for is an informed choice. If you have underlying health conditions it is important to consider any contraindications. For example plants like spinach and arugula are high in vitamin K and may not be suited for people who have kidney stones or those taking blood thinners. Like most things, taking too much of a good thing can have negative consequences. Indeed a lady in Israel who mistakenly ate a full bowl of Wasabi thinking it was guacamole suffered heart arrhythmias. So understanding your own body and listening to what peer reviewed science can tell us is key to building a personal diet against disease. 

As your granny used to say, everything in moderation and you won’t go wrong.

Janet Colston PhD is a pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

Wasabi Japonica is not a name that trips off the tongue when you think of medicinal plants but this ancient Japanese herb is full of functional metabolites with a proven ability to heal disease. The Japanese have known for centuries that Wasabi bestows a remarkable array of medicinal properties with benefits to human health including significant anticancer and antimicrobial functions. Even the heart shaped leaves that grow out of the crown suggest it has cardiovascular benefits as Japanese herbalists used the plant as a vasodilator to improve blood circulation. We delve into these properties and how to grow it successfully to reveal a plant that should be on every health conscious person’s plate.

Botanically it is a member of the Brassica family and thrives in humid mountain river beds in Japan where it is known as SAWA Wasabi.  Alternative soil grown methods (OKA) favouring leaf and petiole production are popular in China, Korea and Taiwan. Wasabi contains similar glucosinolates to broccoli and produces highly bioactive metabolites when enzymes are released during grinding of plant tissue causing its cells to rupture. Hydrolysis of the glucosinolate precursor Sinigrin by the enzyme myrosinase releases a range of volatile Allyl isothiocyanates (AITCs). Wasabi uniquely  contains a higher concentration of the long chain isothiocyanate 6-MITC or 6-MSITC [1]. This reaction to produce 6-MITC reaches maximal effect 5mins after grinding and dissipates again after 15mins as it undergoes further reactions and the effect is reduced. Wasabi like the other crucifers evolved this protective mechanism to prevent predator attack, warning off insects and animals that bite once not to try again [2]. 

If you have never seen Wasabi grated right in front of you, we almost guarantee you have never experienced real wasabi. This is most likely fake wasabi, common with pre-packed sushi and consists of horseradish, food colouring and mustard. If you still feel a sensation after 15mins then you know it’s not the real deal.

What effect does it have on our body? 

The taste of real ground Wasabi is sweet but then it generates heat and pain in nasal passages as the isothiocyanates bind to the Wasabi receptor. That’s right, the Wasabi receptor, technically known as the transient receptor potential ankyrin 1 (TRPA1) channel located on sensory nerve endings in highly innervated areas at the tip of the tongue and nasal passages [3]. It’s a mouthful but TRP channels are a very important defence mechanism adapting the bodies response to a wide variety of stimuli including temperature, nociceptive stimuli, touch, osmolarity and pheromones [4].The TRPA1 channel is well known to be activated by AITC, more commonly known as mustard oil which allows sodium and calcium ions to flood into cells. This induces pain and neurogenic inflammatory responses in expressing sensory nerves resulting in the noxious sensation in the sinuses [5]. 

Anti-Cancer, Anti-Microbial, Anti-Inflammatory, Cardioprotectant 

Japan’s oldest botanical script, the Honzowamyou compiled in 918 is thought to be the first description of Wasabi being cultivated as a medicinal plant [6]. Wooden plant labels with the inscription ‘Wasabi Sansho’ were also excavated in what was thought to be one of the first medicinal herb gardens [7].

Historically the Japanese used ground Wasabi to prevent food poisoning from raw fish and although they were most likely unaware of the mechanism, Wasabi soon caught on and was reserved for the higher classes. We know these early herbalists used Wasabi to treat rheumatic arthralgia, poor blood circulation and as an effective pain reliever [8]. The fresh plant is high in protein, fibre, vitamins B6 and C, and the minerals calcium, magnesium, potassium and manganese. However the main scientific interest lies in the bioactive compounds in Wasabi, the isothiocyanates and p-hydroxycinnamic acid properties [9].  

Overwhelming evidence demonstrates 6-MITC and other phytochemicals in Wasabi extracts are highly efficient in killing cancer cells albeit in the lab and these include lung, breast, colon, pancreatic, oral, blood, skin cancers and bone metastasis [10,11,12,13,14,15,16,17,18,9]. Tumour killing mechanisms involve complex cellular pathways that researchers continue to study in an effort to only kill malignant cells while not disrupting healthy tissue.

According to the World Health Organisation, antibiotics around the world are increasingly resistant (AMR) to infections caused by bacteria, viruses, parasites and fungi and there is a desperate need to look for alternatives [19]. Wasabi may provide an opportunity to exploit its ancient antimicrobial activity. Extracts have shown inhibitory effects on bacteria that cause food poisoning (E Coli, Vibrio), respiratory disease (S Aureus), dental caries ( S Mutans), duodenal ulcers (H Pylori), as well as preventing yeasts, fungi and molds spreading [20,21,22,23,24,25].

Amongst the many other functional effects, Wasabi extracts were found to inhibit platelet aggregation protecting against heart attack and stroke providing a good reason for researchers to examine effects it may have on SARS-CoV2 [26]. Indeed AITC is a potent agonist at the site specific TRA1 channel [27] which elicits peripheral vasodilation and induces a biphasic blood pressure response potentially playing an important role in prevention of cardiovascular disease [28].

As if all these functional properties were not enough, 6-MITC has also been reported as a neuroprotectant [29], preventing  a range of inflammatory conditions [30] and as a potential weight loss promoter [31]. Even more incredible, researchers have found high levels of Isosaponarin in Wasabi which promotes collagen synthesis and stimulates papilla cells in the scalp to promote hair growth [32].

Although there is no direct evidence of Wasabi fighting Coronavirus, previous studies did find extracts had antiviral activity on influenza [33]. Researchers in Thailand are currently working on computational molecular docking data of the SARS-Cov2 genome examining two major active phytochemicals in Wasabi in an attempt to develop a blended tea for treatment of long covid conditions [34].

Is Wasabi really that hard to grow – can CEA enable farmers to grow it with confidence?

Wasabi Japonica may have a built up a reputation as ‘hard to grow’ in traditional farms or commercial polytunnels but we believe Controlled Environment Agriculture (CEA) and careful monitoring holds the key to eliminating most problems suffered by growers.

Wasabi can take up to two years to mature and care must be taken to ensure the conditions are just right. Thousands of years of evolution, growing in the shady humid river beds in the shadow of Mount Fuji in its native Japan can be difficult to replicate. But it is possible despite one of the biggest challenges scaling from pilot to commercial farm.

Manipulating the growing environment of Wasabi throughout the growing cycle with a combination of micro-propagation, LED lights and hydroponics can lead to enhanced plant yields. A range of fertilisers can be applied at different periods of growth through early stages, petiole, flower and stem production in a variety of substrates to optimise biomass. 

High value crop

With a surge in recent years of Sushi bars and restaurants in the US there has been a rise in demand for real Wasabi to accompany fine dining. This has resulted in a relatively high value for fresh Wasabi (circa $250 per kg) due to the low supply in the west and because commercial production is still relatively uncommon outside of Asia. 

Some of the prohibitive reasons are a 2 year growing cycle and the risk of crop loss during this time due to disease. Professionally modelled greenhouse production, continual review of IPM and beginning with clean plant material can help overcome these issues.

Outside of Japan and Asia, growers employ a range of production methods including spring water beds, recirculating gravel beds or soil/coir grown in protective environments or a combination approach to either maximise stem size or increase leaf and petiole production rates. Both SAWA and OKA production lend themselves well to CEA. Size is not everything though as discerning sushi chefs look for colour, stickiness and long lasting flavour and this requires a degree of understanding of different cultivar properties. The two main types of Wasabi cultivated are Daruma and Mazuma although breeders ensure there are many derivatives of these developed for different commercially viable traits. 

Daio Wasabi Farm, Nagano, Japan

In North America, the Pacific Northwest region has one of the most conducive climates outside of Japan for growing Wasabi where many have based their operations. So the question of which method you employ comes back to Chris Higgins saying ‘it all depends’. Whether you aim to grow in shaded river banks, spring water terraces, polytunnels, glasshouses or indoors, all must take into account geographical location of the farm, capital investment, environment monitoring, labor management and long term maintenance protocols. 

Start Clean Stay Clean

This phrase is most associated with integrated pest management (IPM) but here we associate it with fungal endophytes abundant in vascular plant tissue. This can lead to poor growth and disease spread in both hydroponic tanks and soil grown plants if not tightly controlled. Wasabi produces multiple semi mature offshoots that can be harvested and replanted but these will have inherent problems carrying any fungal disease onto the next generation. The way to start clean is to micropropagate new plants via meristem tip culture. The meristem (left image) in pale yellow is just a few millimetres in size and sits proud above swollen basal cells located inside the primordial leaves (middle image). Excising this actively growing area excludes any disease as it is outside the plant phloem bundles that carry viruses. Active meristem tissue can then be promoted in sterile culture to produce a new clean clone (right image).

Wasabi grows well in tissue culture and this can be a fast efficient way to scale large numbers of identical clones for commercial production. Ultimately, integrating a good IPM will alleviate issues with viral transmission, as Wasabi is especially vulnerable to aphid attack in the flowering season. Reducing nitrogen levels in fertilisers during this period is advised. 

Can Wasabi ever be mainstream?

Wasabi not only looks good in the greenhouse, but every part of the plant is edible, including the flower, petiole, leaf and stem. 

The taste is much sweeter and more subtle than fake Wasabi most people know as the lurid green paste in tubes. Powdered wasabi certainly can prolong the shelf-life but this has not caught on and the taste cannot replace the fresh product experience. Fresh leaves have a spicy taste that pep up salads and the stems can be added for crunch or pickled as they do in Japan into Zuki, popular in Shizuoka Prefecture [35]. Sushi, Sashimi and Soba noodles are well established in western diets, and seen as a healthy option. As consumers become increasingly aware of fake condiments it is likely to increase high global demand for fresh grown Wasabi.

Get together with friends and share homemade sushi, it’s one of the healthiest things to eat and we guarantee it’s outstanding when combined with Loch Fyne Scottish Salmon! If you are not too sure then you can learn how to make perfect sushi at the Californian Sushi Chef Institute.  

The future of metabolite Research needs Controlled Environmental Agriculture

Speed breeding Wasabi via controlled environmental agriculture can accelerate production of metabolites. This is a technique being employed by blueberry breeders [36] and can cut down the growing cycle of plants like Wasabi that normally take 2 years to reach maturity. Modelling of glucosinolates in plants grown under different environmental conditions can push our understanding of how Wasabi distributes bioactive metabolites, literally shining a light on the biological mechanisms that cure disease. Below is a series of wasabi root images in our early studies, left shows healthy root growth under RB LEDs, middle is a newly emerged root and right is a RGB confocal overlay image of increased secondary metabolites [37] autofluorescence signal in a root slice indicating cellular fluorophore production potentially due to flavonoids. 

This leads to new research pushing scientific understanding of metabolite production and has proved a successful model for those who grow Wasabi in Asia for large scale powder production for the health and wellness market. 

Our genuine wish is to see diversification of CEA crops to include more complex plants like Wasabi, ensuring this way of growing complements any unique selling points of farmers in what is a very niche market. We have many years experience with Wasabi so if you’re Interested in learning more about growing in a controlled environment, get in touch.

All images unless otherwise stated are courtesy of The Functional Plant Company. 

Janet Colston PhD is a pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

The potato was first domesticated in Peru and Bolivia between 8000 and 5000BC [1]. Andean farmers found they grew well in higher altitudes around the lakes of Titicaca where the ancestors of the Inca settled [2].

Rich in starch, potatoes contain higher vitamin C than oranges, more potassium than bananas, and more fibre than apples [3]. The Spanish introduced potatoes to Europe in the 15th century having realised the food security significance [1]. Almost a century later the governor of Bermuda sent plants to Virginia in the U.S. [4]. It would take another century and a half to become an established crop in the U.S. In the 19th century, potatoes became a staple food, mostly to immigrants from Ireland and Scotland.  During the Klondike gold rush, prospectors prized potatoes as much as the gold they extracted. Although vitamin C was yet to be discovered, the gold diggers knew potatoes contained vital nutrients that helped them to survive in the wild [5].

Western diets have literally been consumed by the potato and all its derivatives but we have forgotten the benefits of other South American/African tubers, namely yacón, sweet potato and yam. Popular in South America and Africa, these are still relatively uncommon SUPERFOODS that grow and adapt well to controlled environments.

Strengthening the Immune System to protect against disease – ‘The Good’

YACóN (Smallanthus sonchifolius)

Yacón is a relative of the sunflower and Jerusalem artichoke. It produces a large tuber with a sweet taste and texture like an apple or watermelon [6].  The edible tuber can weigh from a few hundred grams up to a kilogram. Yacón roots contain inulin, oligosccharides and fructooligosaccharides (FOS), indigestible polysaccharides that pass through the human digestive tract without being absorbed. Yacón has been used to make syrups suitable for diabetic patients, highly valued in Japan for antihyperglycemic properties [7]. However the percentage of FOS versus monomer type sugars can vary with variety, particularly post harvest (personal communications Beotanics Ltd). They showed that monomer sugars increased dramatically within 4 months of storage. Proper variety selection, growing culture, storage temperature and processing are essential to maximise this vegetables unique traits. They have a prebiotic effect, promoting  beneficial gut bacteria to improve gastric health [7]. Yacón leaves also display medicinal properties with protocatechuic, chlorogenic, caffeic, and ferulic acids, which help to lower cholesterol [8]. 

Growing Yacón – Protected Controlled Environment

Yacón products including flour, syrup, juice, concentrate, tea extracts, both fresh and organic are predominantly exported to U..S markets [9]. If you want to grow yacón,  space is a prime consideration as they can grow to over 2m in height. They produce small yellow flowers at the end of the growing season. Although yacón is not photoperiod sensitive, it still requires several months to establish and tubers tend to be late forming with most development happening 5 to 8 months after planting. Yacón does not do well in dry hot summers as it’s unsuitable for maximising high FOS in tubers. The hot climate also makes it susceptible to thrips and whitefly so there is a definite advantage to cooler coastal conditions such as the Pacific Northwest.

SWEET POTATO (Ipomoea batatas)

Sweet potatoes are a member of the morning glory family. They are gathering popularity as a healthy alternative to the starchy potato. Sweet potatoes produce more edible energy per hectare per day than wheat, rice or cassava [10] and are a good source of carbohydrates, fiber, and micronutrients. The edible leaves and shoots contain vitamins A, C and B (Riboflavin) [11]. Orange sweet potato contains high levels of beta-carotene which is converted by the body to vitamin A. They offer a cost-effective, sustainable way to supplement diets with only 125g needed to provide a RDA of vitamin A [12]. 

Purple sweet potato contains 4-7 times higher levels of anthocyanins compared to other sweet potatoes [13]. There is a wide range of genetic variability which leads to some interesting opportunities in the intensity of beta-carotene and anthocyanin, making this crop suitable for future food ingredients and nutraceutical exploration in both leaf and root. Beotanics Ltd are at an advanced stage exploring commercial opportunities in protected and vertical farming possibilities with specially selected genetics for high value applications.

A search for sweet potatoes in the U.S. will take you to California Sweetpotates, family owned farms in Merced, Stanislaus and Kern County. These sweet farmers practise sustainable controlled fertilization and drip irrigation to produce bountiful harvests. They have one of the best sites for learning how to cook with sweet potatoes. So why not make some amazing healthy dishes, we love the grilled sweetpotato tacos with queso fresco and cucumber-tomato salad.

YAM  (Dioscorea)

Some people confuse sweet potato with yam but it bears no relation to yam which are sometimes called true yams so as to make the genus clear.

Yam is a tuber of the Dioscoreacea family, commonly grown throughout African countries predominantly grown for starch. The most common cultivars include white yam (D. rotundata), water yam (D. alata), yellow yam (D.cayenensis), aerial yam (D.bulbifera), Chinese yam (image inset) (D.esculenta) and trifoliate yam (D.dumentorum) [14]. Bulbifera also known as ‘air potato’ is a highly invasive species [15]. The USDA has a citizen science programme to monitor Bulbifera vines and the biological beetles introduced to control their spread in Florida [16]. One of the most under-rated medicinal varieties is the water yam, cultivated in Nigeria for its large roots and edible white and purple flesh [17]. 

Medicinal Properties Water of Yam

Water Yam is a natural source of vitamin C, beta carotene and vitamin B6 with important cardiovascular protectant properties [18]. Traditionally hard to grow, water yam has been difficult to commercialise in comparison to other cultivars. Farmers in Nigeria have concentrated on the more lucrative white yam and mixed crop farming of maize, cassava, cocoyam and sweet potato to ensure food security and protect against crop failure. But water yam is very high in total dietary fiber and has a high amylase content [19], which helps to break down starch. Water yam is also low in sodium and high in potassium, manganese and calcium which has implications in food fortification supporting bone health, metabolism and heart function [20].

Yam has been shown to contain powerful antioxidants with anticancer properties. It has preventative effects against many other ailments including arthritis and gastrointestinal disorders [20]. In turn these antioxidants display anti-inflammatory effects which help control diabetes and obesity as well as related heart disease [20]. A study examining people that ate yam extract for 12 weeks showed improvements in brain function. The effect is thought to be due to diosgenin which promotes neuronal growth [21].  

Circulatory levels of two estrogen hormones, estrone and estradiol typically decrease during menopause, but both hormones can be increased through daily consumption of yam which has been demonstrated to increase levels by more than a quarter [22]. 

Why Yacon, Sweet Potato and Yam need to start clean – ‘The Bad’

Despite being relatively easy to grow, potato tubers have a bad past history and are susceptible to more than 75 diseases [22]. The origins of some of the more serious diseases including blight have since been traced back to Mexico [24]. Early potato blight most often seen in North America is caused by the fungal disease of Alternaria [25], but it is late potato blight caused by Phytophthora infestans that resulted in the devastating mid 18th century European and Irish famines [24]. This also affects other members of the solanacea family including tomatoes. Around the world potato blight causes around $6 billion of damage to crops each year [26].

There needs to be a clear path for viral and fungal free starting material and that starts with plant tissue culture and clean potato seeds.

The solution is to source the best plants for the field from plant micropropagation that guarantees the plants are free from diseases. The International Potato Centre, CIP in Lima is the central genebank for all things potato related in the world, preserving every known tuber germplasm for future biodiversity. We don’t know of many commercial growers of yacón and sweet potato using protective environments but one Irish company, Beotanics in Kilkenny, Ireland are proving it can be done. They hold a wide range of virus free stock  in their laboratories to support over 1000 ha of client crops.

Protected cropping is essential for seed root production planting materials due to sweet potato being very prone to virus. In more temperate regions protected cropping of planting stock is essential as it’s a slip raised crop and huge amounts are needed for a very short planting window. 

Sweet potatoes can be grown using a dripper system which may circumvent contaminated fields allowing time for regeneration of agricultural fields. In Nigeria Professor Morufat Balogun oversees the work done by the Institute of Tropical Agriculture (IITA) on yam seed production from meristem tip culture followed by aeroponic growing in tanks within polytunnels before finally planting out in the field. Commercial crops are subsequently harvested after 5 months with tubers as large as 5Kg. Funded by the Bill and Melinda Gates Foundation hear first hand from Professor Balogun on the impressive work being done in Nigeria in the film below.

Potato Piracy – ‘The Ugly’ 

If you are planning to grow any of these crops, be aware that some have protected status. Cultivar piracy is a real threat to the South American economy who are reliant on the income from native crops.

Feeding future world populations

The potato tuber is the third most eaten crop in the world, but who would have thought the potato could sustain life beyond earth in years to come? Proof of concept experiments are currently taking place to grow potatoes in simulated Martian conditions [27]. So the humble spud is indeed a SUPERFOOD that has survived famines, disasters, maybe even become a sustainable food source for settlers on Mars but for now and more importantly could boost personal immunity to fight disease.

Janet Colston PhD is a pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

By Janet Colston

These are the most common salad items added to our weekly shopping basket and they supplement our food plates adding nutrients to our diets. We want to delve deeper into their additional phytonutrients and this week it’s the ubiquitous Tomato. 

Tomato (Solanum lycopersicum)

Is it a fruit or a vegetable? This is a question that often comes up when people discuss tomatoes. The answer is it’s both; the botanical definition of a fruit is a ripened flower ovary that contains seeds whereas vegetables are roots, leaves, or other secondary parts and generally lower fructose content [1]. Nutritionists consider the tomato a vegetable as they are more likely to be added to savoury dishes although cape gooseberry (physalis peruviana), also called ground cherry tomato or husk tomato is often added to sweet desserts in the UK. Although the ground cherry comes from the same nightshade family (Solanum) as tomatoes, they are a completely different fruit. Tomatillos (physalis isocarpa), also called wild husk or green tomatoes are one of the oldest cultivated plants. Domesticated by the Aztecs as early as 800 BC, they are a great source of nutrition and usually added to pickles and sauces [2].

Tomato consumption is known to reduce risk the of heart disease, cancer and reduces UV damage

Tomatoes contain all the major carotenoids including alpha and beta carotene, lutein and lycopene [3]. They are particularly high in lycopene linked to many health benefits [4]. Lycopene is a naturally occurring red/pink carotenoid pigment found in many other fruits including pink grapefruit, watermelon, papaya and guava. 

Lycopene has been extensively studied for anti-cancer effects linked to a reduction of the risk of prostate, stomach, pancreatic, lung, breast and skin cancer [5][6][7][8][9]. Consuming just 16mg of lycopene from tomato paste daily can dramatically reduce the severity of sunburn and help prevent age related macular degeneration [10][11]. It is generally thought that a diet rich in lycopene can help you live longer and protect the heart, reducing the risk of heart disease and stroke [12] and reduce the chances of premature death by nearly 40% [13]. The average intake of lycopene in the US is around 8mg/day [14], much higher than other countries around the world [15].

The CDC recommends 10 strategies to help increase consumption of vegetables in diets to prevent obesity [16]. Making a basic tomato stock is an easy way to access health promoting ingredients. We love chef Andrew Zimmern’s tomato stock recipe, why not give it a go with peppers, tomatoes and spinach.

Growing Tomatoes

Growing tomatoes in hydroponics can require a degree of knowledge but once mastered growing is straight forward. Generally they are started in ever increasing rockwool cubes and dripper at the base. Temperature range should be around 75-85 Fahrenheit and not allowed to drop below 60 at night. Remember tomatoes need lower nitrogen and higher potassium levels in a tight pH range 5.6-5.8 to ensure good flowering and fruiting. More detailed information is available from Hort Americas with their short course on hydroponic production of vine crops. The “Tomato Greenhouse Roadmap” from Hort Americas is designed to be a step by step guide to growing tomatoes.

Remember!
The CDC recommends the following measures in regard to COVID-19.
How to protect yourself • What to do if you are sick
Disclaimer: We are not doctors and do not prescribe this blog as a medicinal alternative to bona fide medical advice should you contract seasonal flu or Coronavirus.

Janet Colston PhD is a pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

Bell pepper, Leafy greens and Tomato

These are the most common salad items added to our weekly shopping basket and they supplement our food plates adding nutrients to our diets. We want to delve deeper into their additional phytonutrients, this week we discuss healthy leafy greens.

Leafy Greens

Traditionally we think about leafy greens being the lettuce common in our supermarkets, but there is a very wide range of leafy greens, all vying for unique taste, crunch and flavour. 

Microgreens are all the rage but what exactly are they? Generally they are the young seedlings of their more mature parents and are harvested within weeks rather than months making them much more accessible and easy to grow. They are packed full of vitamins and research suggests they contain more antioxidants than mature plants [1]. In a 2011 study, almost all of the microgreens tested had four to six times more ascorbic acid (vitamin C), tocopherols (vitamin E), phylloquinone (vitamin K), and beta-carotene (Vitamin A precursor)  than the mature leaves of the same plant [2]. 

Some leafy greens like spinach and arugula are very high in vitamin K and this can be a problem for people on blood thinners or those prone to kidney stones who may want to avoid large quantities [3].

Some of the most interesting scientific research looking at phytochemical properties in leafy greens has been done by The Watercress Company examining the potential benefits of watercress to human health. Their studies show significant anti-cancer, anti-inflammatory and cardiovascular protective effects in people that consume Watercress daily [4]. More research is underway by The Watercress Research Company examining the biochemical mechanism of urease, an enzyme found in Watercress implicated in a range of pathological states in humans [5].

Cultivating leafy vegetables in a plant factory can help people suffering from very specific conditions. For instance, spinach can be cultivated with a low potassium content to help patients undergoing dialysis [6]. Environmental factors influence the growth of plant metabolites and manipulating these can help elucidate the perfect consistency of medicinal components. The quality and biomass of these plants can also be controlled using light intensity and spectrum. Varying the ratio of red to blue light can increase anthocyanin and ascorbic acid content in lettuce [6]. 

Growing Leafy Greens

Most of the world’s Vertical Farms grow leafy greens of one type or another. Most greens are easy to grow and optimized techniques using CEA have aided large scale commercialization in America’s largest facilities including Aerofarms, Plenty, Square Roots and Bowery. Hort Americas has a useful resource to help beginners grow microgreens and a master class on controlled environment technology can help beginners successfully grow micro herbs.  Hort Americas also recommends Farmer Tyler’s comprehensive road map on growing leafy greens.

Remember!
The CDC recommends the following measures in regard to COVID-19.
How to protect yourself • What to do if you are sick
Disclaimer: We are not doctors and do not prescribe this blog as a medicinal alternative to bona fide medical advice should you contract seasonal flu or Coronavirus.

Janet Colston PhD is a pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.

Bell pepper, Leafy greens & Tomato 

These are the most common salad items added to our weekly shopping basket and they supplement our food plates adding nutrients to our diets. We want to delve deeper into their additional phytonutrients over the next three weeks starting with Bell Peppers.

Bell Peppers (Capsicum annum)

Bell Peppers belong to the nightshade family (Solanaceae) and although technically a fruit they are considered vegetables as they are more likely to be added to savoury dishes. The capsicum family includes both sweet peppers and chilli peppers that are rated for heat and spice on the Scoville scale of heat units. Competition is fierce amongst growers to have the hottest variety on a SHU scale 0-3million [1]. The heat profile was thought to have evolved to deter animal predators but more recent evidence suggests it may also add protection against fungal infections [2]. 

Think Carolina Reaper on one side of the scale with a registered SHU of 2.2million to bell peppers that have zero! Capsaicinoids are responsible for the nip which is felt when it binds to pain receptors in the mouth [3]. Ranging in size and shape, peppers have high nutritional value and properties that can control blood sugar and cholesterol levels as well as improve gut health [4].

Black pepper (piper nigrum) is not to be confused with bell peppers, they are a different species that grow on a vine, flowering and fruiting year round. In Ayurvedic medicine black pepper was used as an expectorant to treat colds and flu viruses [5].

Anti-cancer, Anti-inflammatory, Anti-hypertensive, Anti-obesity

Bell peppers are rich in antioxidants and have a particularly high content of Vitamin C. The vibrant pepper colours reveal a myriad of alpha and beta carotenes, lycopene, lutein, cryptoxanthin and zeaxanthin which increase as they ripen [6]. For this reason they are considered good for eye health, potentially slowing age-related macular degeneration as the carotenoids absorb harmful blue light from entering and damaging the eye [6]. These carotenoids inactivate free radicals preventing some cancers [7] and lowering inflammation in arteries, preventing type II diabetes and heart disease [8].

Peppers contain high levels of Vitamin B6 which helps balance serotonin and norepinephrine in the brain, subsequently releasing melatonin to regulate circadian rhythms and improve sleep patterns [9]. Great for those on shift work patterns. Eating peppers raw helps retain functional properties but if you grow them and want to store for later use, freezing also retains high carotenoid levels [10]. 

Some research also suggests phytonutrients are altered depending on how the peppers are grown. Unexpected results following organic production show higher levels of the flavonoids quercetin and kaempferol [11]. Several studies have now shown a link between people with obesity and type II diabetes having a poor prognosis and outcome if they contract COVID- 19 [12]. Peppers are an easy source of nutrients that can help this vulnerable group boost their immune system.

Growing Peppers

Bell peppers grow exceptionally well in hydroponics and thrive in warm temperatures around 65-75 Fahrenheit during the day with a 10 degree drop at night.  They need a lot of room to grow and require at least 14-18hrs of light a day to produce a harvest in 3months depending on the cultivar. Peppers are usually started from seed or cloned in hydroponics using highly oxygenated water which helps to maintain desired traits of the mother stock plants.

Remember!
The CDC recommends the following measures in regard to COVID-19.
How to protect yourself • What to do if you are sick
Disclaimer: We are not doctors and do not prescribe this blog as a medicinal alternative to bona fide medical advice should you contract seasonal flu or Coronavirus.

Janet Colston PhD is a pharmacologist with an interest in growing ‘functional’ foods that have additional phytonutrients and display medicinal qualities that are beneficial to human health. She grows these using a range of techniques including plant tissue micropropagation and controlled environmental agriculture to ensure the highest quality control.