Abstract

Five bacteria and three fungi were grown and tested against the effects of crude ethanolic, methanolic and water extracts of Bridelia ferruginea leaves and bark. The leaf water extract had zero antimicrobial activity. The overall antimicrobial activity recorded zones of inhibition ranging between 9 and 20 mm. The crude extracts were not active against the fungi tested. The minimum inhibitory concentration (MIC) of the active extracts was determined. Half strength (10 g/ml) concentrations of the bark ethanol and methanol extracts were the MICs against Citrobacter sp. and Bacillus subtilis. While quarter strength (5 g/ml) concentrations of the bark methanol and ethanol extracts were the MICs against Staphylococcus aureus andMicrococcus luteus. The phytochemical analysis carried out on B. ferruginealeaves and bark detected the presence of alkaloids, flavonoids, tannin, cardiac glycosides, anthraquinone, phlobatinnin and saponins and was negative for anthocyanin.

Key words: Bridelia ferruginea, phytochemical analysis, antimicrobial activity, zone of inhibition.