ABSTRACT:
Actinomycetes represent a ubiquitous group of microbes widely distributed in natural ecosystems around the world. They are economically and biotechnologically valuable prokaryotes able to produce wide range of bioactive secondary metabolites useful in medicines like antibiotics, anticancer drugs, immunosuppressant and enzyme inhibitors. In order to facilitate the discovery of novel bioactive compounds from microorganisms, various techniques for isolation of new actinomycetes strains have been followed. A total of eight actinomycetes were isolated from terrestrial soil by spread plate method on Starch casein agar (SCA). Based on the biochemical test and morphological identification four of them were selected and screened for their antimicrobial activity against E.coli and Staphylococcus aureus by agar well diffusion method. Two isolates R1 and R2 have shown the activity against the pathogens. Those isolates were subjected for optimization of various parameters such as carbon sources, nitrogen sources, temperature, pH and NaCl concentration. The isolates were then subjected to solvent extraction using ethyl acetate. Further, the extracts were tested against biofilm forming bacteria Pseudomonas aeruginosa strain NV2 by Micro titer plate assay (MTP) and well diffusion method.