Bioactive secondary metabolites from marine Streptomyces species

Marine Microorganisms and animals are gaining attention biotechnologically for the isolation of bioactive metabolites. An antagonistic marine microorganism was collected from Sundarban, mangrove forest of Bangladesh. The microorganism was identified on the basis of its morphological characteristics as Streptomyces species. It was grown in the yeast-extract glucose broth media at 37.5°C for 7 days for the production of bioactive metabolites. Antibacterial activity of ethyl acetate and chloroform extracts of the culture filtrate was performed against Bacillus subtilis and Escherichia coli. Cytotoxic activity of the extracts were also determined by brine shrimp lethality bioassay. The LC50 values were 2.2, 0.9, and 1.6 µg/ml for chloroform and ethyl acetate extract and cephalosporin, respectively. Further analysis is going on for the isolation of bioactive constituents from the extracts.