In vitro anti-trypanosomal activities of crude extracts, β-sitosterol and α-sulphur from Buchholzia coriacea seed
The seeds of Buchholzia coriacea Engler are traditionally used as a febrifuge in Southeast Nigeria. The bioassay-guided fractionation of the crude extracts was carried out using in vitro cultures of Trypanosoma brucei brucei S427. On soxhlet extraction, methanol gave the highest yield (5.44 %) followed by hexane (3.34%) and ethyl acetate (0.66%). The ethyl acetate extract showed the highest anti-trypanosomal activity followed by the hexane and methanol extracts. Beta-sitosterol and α–sulphur were isolated from B. coriacea seed extracts by preparative chromatography and identified by nuclear magnetic resonance and x-ray crystallography, respectively. Beta-sitosterol and α–sulphur showed modest anti-trypanosomal activities against T. b. brucei S427 in vitro with minimum inhibitory concentration (MIC) values of 12.5 and 25 μg/ml respectively.
Key words: Trypanosoma brucei brucei, Buchholzia coriacea, bioassay-guided fractionation.