When you consider how important agriculture is for African countries, it’s staggering. A whopping 70% of Africa’s population relies on agriculture for their livelihood, and some 30–40% of the continent’s total GDP flows from agricultural products, Sospeter Muhongo of the African regional office of the International Council for Science told me.
It’s no wonder, then, that Africa’s chemists are eager to eke increasingly more sophisticated and economically valuable products out of the continent’s flora.
These efforts are afoot across the continent, but one local example is Lizette Joubert of South Africa’s Agricultural Research Council here in Stellenbosch. One of Joubert’s prime targets is the indigenous herbal tea commonly known as rooibos.
Rooibos, which I’ve been drinking for several years but only on this trip realized came from South Africa, is produced from the Aspalathus linearis plant. It is quite popular among South Africans; in addition, some 11,000 tons of the stuff are exported to the international market each year. Joubert has been working to identify and characterize the various bioactive natural products found in this tea, which is widely touted for its superior antioxidant properties.
Among the molecules present in rooibos, she pointed to aspalathin, a dihydrochalcone and powerful antioxidant that is unique to this plant. With the global antioxidant market topping $3 billion in 2005, she argued that South Africa should further exploit rooibos and other indigenous teas such as honeybush to create novel antioxidant ingredients for cosmetics, food, and nutraceuticals.