Experts discussed these challenges as well as opportunities for change in a meeting ahead of the 73rd International Congress and Annual Meeting of the Society for Medicinal Plant and Natural Product Research (GA) held last week in Naples.
Ashwagandha top of the agenda
Deepak Mundkinajeddu, head of research and development at the Italian sustainable manufacturer Natural Remedies Ltd, explained how global warming is a problem for both water- and heat-loving botanicals, specifically ashwagandha and bacopa.
“The two plants have a contrasting need in agroclimatic conditions for growth,” he said. “Ashwagandha thrives in semi-arid to dry subtropical regions of India, while bacopa is a moisture-loving medicinal herb that needs warm, humid and wet conditions for optimum growth.”
But farmers are under intense pressure to grow more of these plants than ever before, with these botanicals rated as the top four (ashwagandha) and top 34 (bacopa) best-selling herbal supplements in the United States, he said.
What’s more, interest is continuing to rise in the academic world, with PubMed revealing a rising number of ashwagandha focused articles, amounting to around 200 articles per year now.
Describing the impact on the farmers, he noted how they have changed the way they work in order to keep up with demand and accommodate the changing environmental factors.
For example, while ashwagandha is traditionally rain fed, now irrigation is used. Farmers now rotate crops in the field, resulting in the need for pesticides, and producers are using more than just the roots of the plant.
“People are making use of the entire plant—the aerial parts as well as the roots—due to the rising demand, and the aerial parts are cheaper and contain a higher number of withanolides,” Mundkinajeddu said.
However, Ayurvedic texts spanning over 3,000 years recommend only the root for internal use. Leaves were traditionally used topically, if at all.
Regulatory bodies in India and several European countries only permit the root for use in food supplements due to concerns that the aerial parts could potentially have higher concentrations of unwanted, even toxic, compounds.
In fact, it is the introduction of aerial parts that has been blamed for the banning of the botanical for human use in some European countries.
Higher yield, lower quality
Mundkinajeddu noted that the health benefits of medicinal plants are attributed to their complex phytochemical constitution, particularly to the secondary metabolites, but higher yield farming is proving to deliver lower quality ingredient.
He shared research revealing significantly less withanolides in the ashwagandha root than prior to 2018, with around 0.3% to 0.4% w/w and just 0.15% to 0.22% w/w post 2018 and following the surge in demand since the COVID-19 pandemic.
Flooding and contamination
On the other end of the scale is Bacopa monnieri, the water loving plant, which then also requires dry heat for its air drying.
Extended monsoon seasons in India have made it difficult to air dry the plant, and the increased moisture content has led to concerns over risk of ochratoxin A contamination, a potentially carcinogenic compound which can colonize during drying and storage if humidity and temperature are not well controlled.
He added that flooding and movement of water have made it difficult to certify lands for organic cultivation due to pollutants and potential changes in soil compositions.
But, ultimately, he said it’s “confusing for the formulators as well as the consumers to differentiate between the high and low quality products,” thereby making adulteration all the more likely.
Canadian boreal forests and Subarctic
Alain Cuerrier, Vice President of the International Society of Ethnobiology and ethnobotanist at Montreal botanical garden, explained how climate change is rapidly impacting the Arctic, and the Boreal forest in Canada.
He said indigenous communities have voiced their concerns regarding the rapid pace of change and its impacts on medicinal plants.
“In terms of abundance, it’s a big problem and it’s going to be a bigger problem in years to come,” he said.
Cuerrier’s team conducted a study in which they sampled a number of medicinal plants along a latitudinal gradient in order to study the plants’ metabolites, gene expressions and understand how environmental factors linked to latitude have modulated their health benefiting qualities.
Findings revealed a clear link between climate and metabolite concentration, with higher concentration at higher latitudes, until species reach their northern limit, at which point concentrations would taper and eventually reduce.
He said a long-term study is necessary to capture the direction of changes in metabolite composition.
Reducing adulteration
Stefan Gafner, PhD, chief scientific officer at the American Botanical Council, pointed out that price and adulteration are, closely linked.
“Now tariffs are a concern—if prices go up, then we can expect adulteration will increase,” he noted.
“Estimates from systematic reviews on botanical ingredient adulteration suggest that approximately a quarter of the analyzed bulk ingredients and finished products may be adulterated,” he added.
“Climate change is one factor that impacts the availability of medicinal plants as extreme weather conditions may reduce yields, produce raw materials of lower quality and bring new pests into the growing areas.”
One example is saw palmetto, which grows only in the Southeastern USA. He said manufacturers have stated that climate change has a big impact on the supply chain. In years when the saw palmetto harvest is low, fake saw palmetto extracts are more abundant.
Anna Mula, head of quality at Spanish manufacturer EuroMed, gave a presentation focused on the rising demand for saw palmetto and the fact it is one of the most adulterated products on the market as a result of this demand, alongside changing weather and fluctuating harvests.
However, Dr. Gaffner said data to link adulteration directly to climate change are difficult to obtain.
“Similarly, data on the connection between sustainable agricultural practices and adulteration are not readily available,” he added.
According to his evaluation of data from five publications investigating the authenticity of 76 commercial bilberry (Vaccinium myrtillus), broccoli (Brassica oleracea) sprouts, elder (Sambucus nigra) berry, gingko (Ginkgo biloba) leaf, and passionflower (Passiflora incarnata) herb dietary supplements and herbal medicinal products, 41 of 70 (59%) conventional products were adulterated. None of the six products labeled as “certified organic” or “made with organic” were adulterated.
Scientific lab certification
Providing an academic’s perspective, Dr. Gaia Scalabrino, executive director at NatPro Trinity Centre for Natural Products, Ireland, said sustainability should be a priority for everyone in the production chain of botanical supplements.
She told attendees that laboratories are recognized as environmentally intensive facilities, and promoting sustainable laboratory practices is a goal endorsed by the United Nations and recently by EU funding bodies.
NatPro research center at Trinity College Dublin is focused on developing sustainable innovations and bio-based solutions from natural products for pharmaceuticals, functional foods and cosmetics.
The center is an early adopter of international green certifications, and Dr. Scalabrino highly recommended the My Green Lab certification scheme for any other lab workers or directors looking to improve their environmental footprint.
“There are 14 modules that go from energy use to solvents to travel to procurement,” she said. “We made changes to the amount of water we were using, we started monitoring the energy we were using, changing solvents, using less plastic.
“Your end products and end research will have less impact on the environment, and in terms of the culture you create within the team, it’s much more positive,” she added.
