10.22376/ijpbs.2019.10.1.p1-12 Volume 3 Issue 3 2012 (July - September) The ethnobotanical efficacy of Indian Medicinal plants leaves of lessThan i greaterThan Avicennia marina, lessThan /i greaterThan lessThan i greaterThan Caesalpinia Pulcherrima lessThan /i greaterThan and lessThan i greaterThan Melastoma Malabathricum lessThan /i greaterThan was evaluated against Gram positive ( lessThan i greaterThan Staphylococcus aureus, lessThan /i greaterThan ) and Gram-negative ( lessThan i greaterThan Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa) lessThan /i greaterThan bacteria. Leaves were extracted using different solvents such as hexane, chloroform, ethyl acetate and methanol by soxhlet extraction method. The antibacterial activity was evaluated using agar well diffusion method. The plant extracts showed antibacterial activity against the four bacterial species taken in the present investigation. Among treatments, maximum invitro inhibition was scored in the extract of the plant lessThan i greaterThan Avicennia marina lessThan /i greaterThan followed by lessThan i greaterThan Caesalpinia lessThan /i greaterThan lessThan i greaterThan Pulcherrima lessThan /i greaterThan and lessThan i greaterThan Melastoma Malabathricum lessThan /i greaterThan . All plant extracts showed significant zone of inhibition for lessThan i greaterThan Staphylococcus aureus lessThan /i greaterThan than for other bacterial species taken for the study. Among the four solvents tested the methanol and ethyl acetate extracts were more potent in their antibacterial activity. Preliminary phytochemical screening was also done for the leaves extract of lessThan i greaterThan Avicennia marina, lessThan /i greaterThan lessThan i greaterThan Caesalpinia Pulcherrima lessThan /i greaterThan and lessThan i greaterThan Melastoma Malabathricum. lessThan /i greaterThan The results obtained in the present study shows that lessThan i greaterThan Avicennia marina lessThan /i greaterThan , lessThan i greaterThan Caesalpinia pulcherrima lessThan /i greaterThan and lessThan i greaterThan Melastoma Malabathricum lessThan /i greaterThan can be used in treating diseases caused by the test organisms. A Sheela Devi, Johanna Rajkumar, M Rajathi D Modilal, R.Ilayaraja Medicinal plants, antibacterial activity, phytochemical screening, leaf extracts, Avicennia marina, Caesalpinia Pulcherrima and Melastoma Malabathricum 698-705