University of Venda, South Africa
Isaiah DI Ramaite has done his PhD in Physical Organic Chemistry from Rhodes University. He has been lecturing at higher education for the past 20 years. His main research interest is organic synthetic chemistry of heterocyclic compounds and also natural products chemistry of plants that are currently being used by traditional healers in Limpopo Province, South Africa. He is also interested in chemical education for both high school learners and undergraduate university students.
The Limpopo province has a rich biodiversity of a wide range of plants which are currently being exploited by traditional healers for the treatment of various diseases. As part of an ongoing research programme in natural products at the University of Venda, we have been interested on Terminalia sericea Burch ex. DC. Ethno medicinal information revealed that the fruit, leaves, stem bark and roots of T. sericea are commonly used for the treatment of coughs, skin infections, diabetes, diarrhea, and gonorrhea. Anolignan B and termilignan B isolated from the root have been reported to possess antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. The aim of our study was to isolate, purify and evaluate the biological activity of various fractions and pure compounds. Various spectroscopic techniques such as 1D and 2D, HRMS and IR were used to elucidate the structures of pure compounds. This study has shown that the antibacterial constituents of T. sericea root cannot be limited to compounds with lignan structure which have been isolated previously from fractions obtained from mixture of hexane and ethyl acetate using silica gel. The presentation will focus on the results of antibacterial activity against diarrhea pathogens and skin infection organism, and isolated compounds responsible for these activities including their structural elucidation