Phytochemical and Anti-microbial Screening of the Leaves and Twigs of Sclerocarpus africanus (Jacq)

Aim: To determine phytochemical constituents and antimicrobial activity of leaves and twigs of Sclerocarpus africanus (Jacq); prove or otherwise ethno-medicinal claims on S. africanus.

Place and Duration of Study: Departments of Chemistry, Biological sciences and Microbiology, Ahmadu Bello University Teaching Hospital, Zaria, between June to October, 2010.

Methodology: Petroleum ether, ethyl acetate, ethanol and methanol extracts of leaves and twigs of S. africanus were phytochemically screened for the presence of carbohydrates, saponins, tannins, alkaloids, anthraquinone glycosides and flavonoids. Minimum bactericidal/fungicidal concentrations (MBC)/(MFC) and Minimum inhibition concentration (MIC) were carried out on the extracts using Broth dilution method.

Results: Phytochemical screening showed presence of carbohydrates, tannins and saponins. Flavonoids and anthraquinone glycosides were found only in the ethanol and methanol extracts. Anti-microbial screening of methanol and ethanol extracts showed activity against the following human pathogens: Staphylococcus aureus, Salmonella typhi, Streptococcus pyogenes, Shigella dysenteriae, Candida albicans and Candida thrusei, with MIC value of 2.5 mg/ml; while Neisseria gonorrhea was inhibited at MIC 1.25 mg/ml. MBC/MFC value of 10 mg/ ml was observed for all the pathogens, except N. gonorrhea which had an observered MBC of 5 mg/ ml for ethanol extract. Similar MBC/MFC values were obtained for methanol extract except Shigella dysentereae which had MBC of 5 mg/ ml. Petroleum ether extract was active against S. aureus, S. typhi, S. dysenteriae and N. gonorrhoea with MIC value of 5 mg/ml and MBC/MFC value 10 mg/ml; no activity was observed for S. pyogenes, C. albicans and C. thrusei; N. gonorrhea was most inhibited.

Conclusion: Results obtained justify the ethno-medicinal use of this plant in treatment of gonorrhea and other venereal diseases caused by the test micro organisms.