SECONDARY METABOLITES ISOLATED FROM TWO MEDICINAL PLANT SPECIES, BRIDELIA MICRANTHA AND SIDEROXYLON INERME AND THEIR ANTIOXIDANT ACTIVITIES.

The indigenous medicinal plant species, Bfidelia micrantha and Sideyoxylon ineime (both known as 'uMhlalamagwababa' in isiZulu), are used interchangeably by traditional healers in KwaZulu-Natal, South Africa, to treat a variety of ailments due to morphological similarities. In this study, a phytochemical investigation was done on B. inicrantha and S. inenne to determine if they have a chemotaxonomic link. Three penta- cyclic triterpenes, one carotenoid and one megastigmane were isolated from S. inerme. Two flavonoids and two triterpenes were isolated from B. micrantha. These compounds were not previously isolated from these plant species. The antioxidant capacity of the isolated flavonoids was comparable to that of the known antioxidant - ascorbic acid. Profiling of the fruit extracts from both plant species by gas chromatography-mass spectrometry showed different classes of compounds in the extracts. This study corroborates the use of S. inerme and B. mici-ntha by traditional healers but does not support their use interchangeably.