South Africa’s indigenous medicinal plants could be the farming crops of the future, Dr Sue Taylor tells Roelof Bezuidenhout.
Not long ago researchers studying the chemical properties of muthi plants were accused by outsiders of dabbling in witchcraft. Now, with more and more entrepreneurs basing businesses on indigenous plants, it makes sense that the next step is cultivating these species to meet the demand. Communities, traditional healers or commercial farmers could all help ensure a steady supply of these valuable plants and prevent their over-exploitation, says Dr Sue Taylor of the University of the Free State’s Centre for Development Support and Arid Areas Programme.
“Local and international researchers are involved in legitimate drug discovery and development programmes, aimed at using these plants to battle some of Africa’s key infectious and non-communicable diseases,” explains Dr Taylor.
Research creates commercial medicines
Dr Taylor is a long-standing member of the Indigenous Plant Use Forum (IPUF), established by the National Research Foundation to ensure ongoing research into medicinal plant biodiversity. She says academics know their research needs to contribute to new commercial ventures based on indigenous biodiversity. “Research can create opportunities for partnerships with communities and entrepreneurs,” she points out.
“In the laboratory, chemical and biochemical tests can confirm that plants’ locals use has valuable or interesting chemicals. These can be isolated and tested to confirm activity against microbes and cancer cells, and how they compare to existing medicines.” “We have to know how to make cost-effective palliatives from these plants, which can then be distributed through clinics and home-based care groups. Without research commercialisation would be impossible.”
Dr Taylor notes that arid plant species, such as the now famous Hoodia gordonii, have always been part of indigenous people’s medicine chest, but have received a modern makeover with high throughput screening and laboratory testing, product development and patents. The key, however, is to ensure that communities benefit from what is essentially their heritage. “The medicinal value of a variety of plants still needs further investigation,” she adds. “Sutherlandia, for example, grows widely in the arid areas of South Africa and is known as kankerbos by locals.
“Although there are only limited human trials currently underway, studies show remarkable remission of near-fatal human tumours after regular imbibing of sutherlandia tea. It’s especially effective against pancreatic cancer and diabetes.
“Carpobrotus edulis (wild fig), which is an arid area succulent plant, is known as a curative agent for skin maladies. It also has antioxidant properties when taken internally and could be valuable in preventing colon cancer.”
Healing animals – and land
There’s also scope for indigenous plants in ethnoveterinary medicine, a fairly new field in South Africa. Current research is testing and validating remedies that communal livestock farmers use, which will empower all local stock farmers to dose their animals with confidence. Indigenous plants can also play dual roles. “Lippia scaberrima – used as an essential oil – is part of a project on the Highveld gold and uranium mines to restore the ecological functioning of toxic mine dumps, while providing an income for communities,” says Dr Taylor. “Many landscapes in South Africa’s arid areas need reclamation and could be given over to communities for similar cultivation projects, although it would be a challenge to find tough plants that also deliver a valuable product. We expect a similar investigation for the proposed uranium mines outside Beaufort West might yield interesting findings and opportunities.”
Problems beyond the lab
But the challenges don’t stop in the laboratory. “Many local producers of natural products, such as the Agave Distillers in Graaff-Reinet, struggle to reach international markets, which are complex, competitive and far away,” says Dr Taylor.
“Quality control of herbal products is often another problem – products are often adulterated, an especially pervasive issue in the hoodia trade. South African researchers are developing ways to detect non-hoodia ingredients.” She also warns that more must be done to conserve medicinal resources in the wild. “For example, Mpumalanga provincial nature conservation officials say coal-mining is destroying Highveld grassland and associated medicinal plants.”
“But it’s not only the mining operations that do damage – mining staff gain access to pristine areas and soon plants are stripped for sale in the booming muthi markets. Mining companies and nature conservation need to work together to solve this problem.” There‘s concern that government’s complex new access and benefit-sharing regulations, aimed at indigenous knowledge and bio-prospecting, will severely limit many of the commercialisation projects initiated by academic research at local universities.
However, Dr Taylor says these regulations should prevent these resources being stolen from the country to create valuable products elsewhere.
Contact Sue Taylor on (011) 486 2377 or 082 373 7714 or e-mail
[email protected]. |fw