ANTIMICROBIAL ACTIVITIES OF LEAF OF VITEX DONIANA AND CAJANUS CAJAN ON SOME BACTERIA

Abstract

Antimicrobial activities of acetone, ethanol, methanol, hot and cold water extracts of leaves of Vitex doniana and Cajanus cajan on Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Bacillus subtilis and Staphylococcus aureus were investigated. V. doniana and C. cajan contain alkaloid, tannins, saponins, carbohydrates and proteins at varying levels. Antimicrobial activity was particularly high in acetone extracts of V. doniana against S. typhi (19.71mm), followed by methanol extracts of V. doniana against E. coli (14.61mm) and ethanol extracts of V. doniana against S. typhi (13.66mm). Ethanol, methanol and acetone extracts of C. cajan inhibited growth of E. coli to 11.90 mm, 11.69 mm and 10.2 mm respectively. P. aeruginosa was generally resistant to all the extracts accept acetone extract of V. doniana. The minimum inhibitory concentration (MIC) of the extracts was determined. MIC for acetone extracts of C. cajan against E. coli was 0.78mg/ml. The kinetic of kill of individual cells by addition of extract to culture broth indicated decrease in the number of the viable counts during the period of monitoring. Analysis of variance showed that there was no significant difference (p=0.05) between the antimicrobial activity of standard antibiotic gentamicin and acetone extract of V. doniana or C. cajan on the isolates. This result suggests that the acetone extracts of V. doniana and C. cajan have antimicrobial properties which can be pharmaceutically exploited. (Researcher. 2010; 2(3):37-47). (ISSN: 1553-9865).