Phytochemical and in vitro antimicrobial evaluation of the stem bark of Schumanniophyton magnificum (Rubiaceae).

Abstract

The methanolic extract of the stem bark of Schumanniophhton magnificum (Rubiaceae) was screened for its phytochemical constituents and in vitro antimicrobial property using standard procedures. The results revealed the presence of alkaloids, flavonoids, polyphenols, sugars and steroids. A chromatographic separation of the extract led to the isolation of three compounds among which two were identified respectively to noreugenin and AŸ-sitosterol. The extract and the identified compounds were evaluated for their antimicrobial activities in vitro, against some pathogenic clinical isolates, including Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, Staphylococcus saprophyticus, Shigella flexneri, Salmonella typhimurium and Candida albicans, through the disc-diffusion method. Noreugenin showed antibacterial activity against S. typhimurium, with an inhibition diameter of 11 mm.