The potential of South African plants in the development of new medicinal products

Southern Africa is an important focal point of botanical and cultural diversity but only a few plant species have hitherto become fully commercialised as medicinal products. In recent years there has been an upsurge in research and development activity, resulting in several new products and new crops. In this review, more than 90 of the best-known and most promising indigenous South African plants are listed and subjectively evaluated in the context of their potential for commercialisation as medicinal products for a variety of applications. The history of product development relating to the following species is briefly discussed and the plants and some of their products are illustrated: Agathosma betulina (buchu), Aloe ferox (bitter aloe), Artemisia afra (African wormwood), Aspalathus linearis (rooibos tea), Bulbine frutescens (burn jelly plant); Cyclopia genistoides (honeybush tea), Harpagophytum procumbens (devil's claw), Hoodia gordonii (hoodia, ghaap), Hypoxis hemerocallidea (“African potato”), Lippia javanica (fever tea), Mesembryanthemum tortuosum (= Sceletium tortuosum) (kanna, kougoed), Pelargonium sidoides (“Umckaloabo”), Siphonochilus aethiopicus (African ginger), Sutherlandia frutescens (= Lessertia frutescens) (cancer bush), Warburgia salutaris (pepperbark tree) and Xysmalobium undulatum (“Uzara”). The main factors that are apparently responsible for failure or success will be highlighted, especially the importance of marketing strategy, proof of concept and barriers to market entry.