Antibacterial activity of root and leaf extracts of <i>Jatropha zeyheri</i> Sond (Euphorbiaceae)

Abstract

Resistance of human pathogenic bacterial strains results in selective pressure against known antibiotics. Jatropha zeyheri is used by traditional medicine practitioners in the treatment of sexually transmitted and urinary tract infections. Acetone, methanol and ethyl acetate extracts of both leaves and roots of Jatropha zeyheri collected from Capricorn District, Limpopo Province, South Africa were investigated for antibacterial activity, against 14 human pathogenic bacterial strains, using disc diffusion method. Ethyl acetate extracts exhibited activity against 11 of the selected strains and showed zone of inhibition of 10.7 mm against Klebsiella pneumoniae. Largest zone of inhibition of 12 mm was obtained with the acetone leaf extract against Enterobacter cloacae and Acinetobacter calcaoceuticals and methanol extract of the leaf against Enterococccus faecalis. Acetone extract of the root exhibited minimal inhibitory concentration (MIC) of 0.39 mg/ml against Salmonella spp. followed by methanol and acetone extracts of the root (0.78 mg/ml) against Serratia marcescens. Methanol extract of the leaf exhibited MIC of 3.13 mg/ml against Staphylococcus aureus. This study validates the use of Jatropha zeyheri in the treatment of various illnesses.

Keywords: Inhibition zone, antibiotics, Jatropha zeyheri, disc diffusion, MIC

African Journal of Biotechnology Vol. 12(5), pp. 476-480