10.22376/ijpbs.2019.10.1.p1-12 Volume 4 Issue 1 2013 (January - March) Based on the traditional usage, lessThan i greaterThan Moringa oleifera lessThan /i greaterThan and lessThan i greaterThan Allamanda cathartica lessThan /i greaterThan plants were selected. The present study is to find out its antimicrobial potential against clinical isolates of KMCHospital. The resistant patterns of the isolated pathogens were studied against commercial standard antibiotics. By using the different polar solvents (Methanol, Ethanol, Chloroform, Water, Petroleum ether and Ethyl acetate), the plants material were extracted and studied their phytochemical constituents. Antimicrobial activity of plants extract were studied by well diffusion assay in muller hinton agar and minimum inhibitory concentration of the significant extracts were studied by tube dilution assay. The results of lessThan i greaterThan A. cathartica lessThan /i greaterThan antimicrobial property revealed that petroleum ether extract showed good inhibition ( lessThan i greaterThan Staphylococcus aureus lessThan /i greaterThan (20mm), lessThan i greaterThan Escherichia coli lessThan /i greaterThan (13mm), lessThan i greaterThan Pseudomonas aeruginosa lessThan /i greaterThan (19mm), lessThan i greaterThan Acinetobacter sp lessThan /i greaterThan (20mm), lessThan i greaterThan Proteus sp lessThan /i greaterThan (18mm)) than that of remaining extracts. lessThan i greaterThan M. oleifera lessThan /i greaterThan ethanol extract showed significant inhibition ( lessThan i greaterThan S.aureus lessThan /i greaterThan (20mm), lessThan i greaterThan E.coli lessThan /i greaterThan (20mm), lessThan i greaterThan Bacillus sp lessThan /i greaterThan (18mm), lessThan i greaterThan P. aeruginosa lessThan /i greaterThan (14mm), lessThan i greaterThan Cornebacterium sp lessThan /i greaterThan (12mm), lessThan i greaterThan Klebsiella pneumonia lessThan /i greaterThan (12mm), lessThan i greaterThan Acinetobacter sp lessThan /i greaterThan (14mm)). Acute toxicity was performed in albino mice and up to 1000mg/kg, no toxic symptoms were observed. These results suggested that both the plants showed relatively broad spectrum of antimicrobial activity and are non toxic. KARTHIC RAJAMANICKAM AND SINGARAM SIVASUBRAMANIAM SUDHA Moringa oleifera, Allamanda cathartica, pathogens, toxicity, antimicrobial 768-775