Antibacterial potential of the 80% methanol and chloroform extracts of Clematis hirsuta

Abstract

The leaves and roots of Clematis hirsuta Perr and Guill is traditionally applied to heal respiratory tract and for the treatment of various animal diseases in different regions of Ethiopia. The objective of this work is to evaluate the antibacterial activities of C. hirsuta. The leaves were collected and air dried in shade at room temperature, made into powder and was soaked in 80% methanol and chloroforms (1 g: 10 ml). The powder was placed in a shaker for 72 h at room temperature. The extract was prepared in 3% Tween 80 for antibacterial test. The antibacterial activities and the minimum inhibitory concentration (MIC) test were determined by paper disk diffusion and agar dilution methods respectively. The 80% methanol and chloroform extract of the leaves of C. hirsuta showed significantly higher inhibition zone than the negative control on some pathogenic bacteria (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Shigela boydii and Salmonella thyphi), but the extracts had significantly lower inhibition zone than the standard drugs (chloramphenicol and ampicilin). The chloroform crude extract of the leaves C. hirsuta showed the best inhibition zone (12.33±0.50) on P. aeruginosa at 200 mg/ml concentration. The chloroform extract of C. hirsuta had the lowest MIC and minimum bactericidal concentration (MBC) at 3.125 and 6.25 mg/ml on P. aeruginosa, respectively. The 80% methanol C. hirsuta leaf extract was not toxic at 500, 1000 and 2000 mg/kg body weight to albino mice. Keywords: Inhibition zone,acute toxicity,minimum inhibitory concentration, minimum bactericidal concentration.