Short communication: In Vitro Antibacterial Activity of Leaf and Root Extracts of Clitoria ternatea Linn.

Abstract

The methanol extracts of the leaves and root of Clitoria ternatea Linn. were tested for their antibacterial activity against different pathogenic drug resistant Gram-positive and Gram-negative clinical isolates procured from Eastern India where there is a very high prevalence of drug resistance due to self medication arising mainly out of ignorance and poverty. The minimum inhibitory concentration (MIC) was determined
by agar dilution technique followed by estimation of zone of inhibition against the selected strains by disc diffusion technique and comparison was done with reference to the standard antibiotic ciprofloxacin. The leaf was found to possess powerful antibacterial activity against Escherschia coli and Vibrio cholerae, which are known to cause dysentri, and Staphylococcus aureus one of the causative agents of fever. The root extract also showed antibacterial action but it was much weaker than that of the leaf extract. Both extracts
were shown to be bactericidal in their mode of action. Quercitin may contribute to the activity of the leaf extract as it was previously reported to be one of the constituent of the leaves of C. ternatea.

Keywords: methanol extracts, Clitoria ternatea, antibacterial activity, minimum inhibitory concentration, agar dilution technique

Ethiopian Pharmaceutical Journal Vol. 25 (2) 2007: pp. 145-150