A COMPARATIVE STUDY ON ANTIBACTERIAL ACTIVITIES AND CYTOTOXIC PROPERTEIS OF VARIOUS LEAVES EXTRACTS OF AVERRHOA BILIMBI

The study was carried out to assess the antibacterial & cytotoxic activities of extracts from leaf parts of the plant, Averrhoa bilimbi. Ethanol, methanol and water were used as solvents and antibacterial & cytotoxic effects were measured using disc diffusion test & brine shrimp lethality bioassay (BSLB). The susceptibility of the microorganisms to the extracts of this plant was compared with standard antibiotic cefadroxil. Water extract exhibited more potent antimicrobial activity by inhibiting wide range of gram positive and gram negative bacteria in comparison to ethanolic and methanolic extract of leaves of A. bilimbi. On the other hand, the ethanolic extract of A. bilimbi leaves( EEL) was found to be the most toxic to Brine Shrimp nauplii, with LC₅₀ of 3.7 μg/ml whereas anticancer drug vincristine sulfate (VS) proved LC₅₀ value 1.73 μg/ml indicating that the potent cytotoxic  compounds in this plant have affinity for non- polar solvents. The spectrum of activity observed in the present study may provide the indication that the plant could be a possible source to obtain new and effective antibacterial & cytotoxic agents. Hence further study should be needed for the isolation of the therapeutic antibacterials & cytotoxic agents from the leaves extract of A. bilimbi.