Emerging and re-emerging infectious diseases and spread of deadly drug-resistant strains pose a challenge to public health care services. Several micro organisms’ derived antibiotics are currently in use to treat a variety of infectious human disease. Broad spectrum antibiotics lead to killing of friendly bacteria in the colon, allowing yeast and other unfriendly microbes to multiply out of control. Medicinal plants would be the best source to obtain a variety of drugs as the phyto-chemicals are more specific, biodegradable and are suppose to have fewer side effects. In the present study we use three naturally available medicinal plants named Catharanthus roseus, Rosa indica, Nerium indicum . Plants extracts were obtained according to some standard method and micro-organism was procured from IMTECH Chandigarh for the evaluation of activity of plants extract.MIC was calculated for each of abstract and ANTIBACTERIAL SUSCEPTIBILITY ASSAY was performed with different micro-organism. Results of the present investigation reveal the antibacterial nature of extracts of different parts (viz., leaf, stem, and root) of Catharanthus roseus var rosea, leaves of C.roseus var alba and oscillatus. Это и многое другое вы найдете в книге Phytochemicals: A Substitute for Tradional Antibiotics (Kamal Ahmad and Shanu Hoda)