African Journal of Biotechnology Vol. 6 (7), pp. 890-893, 2 April 2007   

ISSN 1684–5315 © 2007 Academic Journals        

Full Length Research Paper

Phytochemical and antimicrobial activity of ethanolic extract of Landolphia owariensis leaf

L. A. Nwaogu*, C. S. Alisi, C. O. Ibegbulem and C. U. Igwe

Department of Biochemistry, Federal University of Technology, Owerri, Nigeria.

*Corresponding author. Email: nwogulinus@yahoo.com. Tel: +234 0803 751 0952.

Accepted 29 January, 2007

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 for Staphylococcus sp., 1000 mg/ml for Proteus sp. and 1800 mg/ml for E. coli.

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