The success of chemotherapy lies in the continuous search for new drugs to counter the challange posed by resistant bacterial strains. The aqueous leaf extract of Clerodendrum serratum Linn. tradionally used in folklore medicine for the treatment of various ailments was investigated for invitro antibacterial activity aganist five bacterial pathogens namely staphylococcus hominis ATCC27844, Pseudomonas putida ATCC2021, Proteus vulgaris ATCC13315, Bacillus subtilis ATCC2063 and Escherichia coli ATCC2065.The antibacterial activity of the aqueous extract was determined by employing agar disc diffusion method. Among the various concentrations used, 100mg/ml of aqueous leaf extract was found to be more effective against all tested microorganisms. The highest activity was recorded aganist Escherichia coli ATCC2065 at a concentration of 100mg/ml Proteus vulgaris ATCC2021 with zone of inhibition 17±0.52mm and the lowest activity was recorded aganist Proteus vulgaris ATCC2021 at a concentration of 25mg/ml with zone of inhibition1±0.09mm. Therefore, it was found the inhibitory activity of ethylacetate leaf extract of Clerodendrum serratum Linn. was found to be concentration dependent. The results of this study provides justification for the use of this plant in folkloric medicine for the treatment of various dreadful ailments.
