Abstract

Ethanolic extract of the leaves of Landolphia owariensis were subjected to phytochemical screening and antimicrobial activities on Escherichia coli, Staphylococcus sp. and Proteus sp. using dehydrogenase assay method. The phytochemical screening indicated the presence of alkaloids, flavonoids, tannins and saponins. The bacterial isolates were exposed to different extract concentrations (20 – 2000 mg/ml) of the extract in nutrient broth, and their response was concentration dependent. In all three bacteria, dehydrogenase activity was progressively inhibited at concentrations of about 20 mg/ml, with total inhibition observed with 700 mg/ml forStaphylococcus sp., 1000 mg/ml for Proteus sp. and 1800 mg/ml for E. coli.

Key words: Phytochemical activity, ethanolic extract, Landolphia owariensis, dehydrogenase assay.