Abstract

The antimicrobial activity has been reported from the species of the genus Lactuca. However, there has been no report available on antibacterial activity in the aerial parts of Lactuca runcinata DC. This study was designed to determine the antibacterial activity of methanol extract of Lactuca runcinata DC. The Lactuca runcinata DC showed satisfactory results against almost all the organisms, among them against Staphylococcus aureus and pseudomonas mirebelis showed highest zone of inhibition 17.8 mm and 16.5 mm (0.4g/ml) with the MIC values of 0.04 mg/ml and MBC values of 0.16mg/ml. Other pathogens like Escherichia coli, Salmonella paratyphi showed good zone of inhibition 13.6 mm and 13.9 mm (0.4g/ml) with less minimum inhibitatory concentration of 0.08 mg/ml and MBC values of 0.32 mg/ml for the above mention bacteria. But Salmonella typhi was found to be resistant with more MIC, more MBC value and with a very less zone of inhibition of 8.4 mm (0.4g/ml) when compared with the standards. The present studies revealed that Lactuca runcinata have significant antibacterial activity. So, the potent antibacterial phytochemical are present in the methanol extract of Lactuca runcinata DC.