The in vitro antimicrobial activity of fruit and leaf crude extracts of Momordica charantia: A Tanzania medicinal plant

Objective: To evaluate the antimicrobial activity of Momordica charantia extracts on reference strains and microorganisms isolated from clinical specimens. Method: Petroleum ether and methanolic crude extracts of fruits and leaves of the plant were evaluated for antimicrobial activity using the disk diffusion method on four reference microorganisms (Pseudomonas aeruginosa, Escherichia coli, Candida albicans and Staphylococcus aureus; and four clinical strains of Klebsiella pneumoniae, Proteus vulgaris, Salmonella typhi and Cryptococcus neoformans. Result: Antimicrobial activity was observed against all the tested microorganisms with exception to P. mirabilis and C. neoformans. Methanolic crude extracts exhibited relatively broader antimicrobial spectrum of activity than petroleum ether extracts with the as lower concentration as 0.075 mg/mu l. Methanolic fruit crude extract displayed the broadest antimicrobial spectrum by inhibiting majority (75%) of the tested microorganisms. Neither was there synergistic nor addition effect upon mixing leaf and fruit extracts of equal concentrations derived from the same solvent. Conclusion: Extracts of M. charantia demonstrated antimicrobial activity on tested microorganisms except on Proteus mirabilis and Cryptococcus neoformans. Fruit extracts showed higher antimicrobial activity than leaf extract. Further studies are recommended that will involve various parts of the plant, select different fractions of extracts and purify the active antimicrobial components.