The Department of Chemistry

My research is focused on the discovery of biologically active compounds with varying structural diversity from terrestrial plants and marine organisms (examples 1 and 2). Specimens are collected and extracted exhaustively to yield crude extracts, which are screened in several benchtop bioassays to determine biological activity. The active extract is then fractionated using the full spectrum of chromatographic techniques, including HPLC. Structural elucidation of the pure compounds utilizes various spectroscopic techniques such as UV, IR, MS, and NMR, as well as X-ray crystallography. In conjunction with colleagues at universities abroad and our own facility at the department, these pure compounds are screened in several bioassays which include antimicrobial, antioxidant, antifeedant, anti-inflammatory, mosquitocidal, nematocidal and cytotoxicity.

In addition, biologically active compounds, which are isolated in large quantities, will be subjected to structure-activity relationship studies. This will involve the chemical modification of the compound using simple chemical reactions such as hydrolysis, esterifications, oxidations and reductions. These derivatives will then be bioassayed and the results analyzed to determine which part(s) of the molecule is responsible for the biological activity. This information is very useful for the worldwide drug discovery programme, the pharmaceutical and agrochemical industries.