ACTINOMYCIN “D” FROM MARINE SEDIMENT ASSOCIATED STREPTOMYCES CAPILLISPIRALIS MTCC10471

In our screening program for new bio-active metabolites from marine actinomycetes, a cyclic depsipeptide wasfound in the fermentation medium of marine Strepromyces (SS23/4) isolated from sediments collected from Bayoff Bengal, vellampattai,Tamilnadu. It showed strong biological activity against gram-positive / gram negativebacteria by agar overlay technique. It was taxonomically characterized by the basis of morphological andphenotypic characteristics, genotypic data and phylogenetic showing Streptomyces sps. Bio active compoundwas obtained by solvent extraction and purification using column chromatography followed by reverse phaseHPLC. The pure compound had potent activity against Mycobacterium tuberculosis and Multi Drug ResistantMycobacterium tuberculosis strains (437RU) at a concentration of 10 μg/mL, and The minimum inhibitoryconcentration (MIC) against standard test organisms was found to be 1μg/mL against B.subtilis, E.coli andMethicillin resistant Staphylococcus aureus. The compound exhibited potent cytotoxic activity against breastcarcinoma (MCF-7), melanoma cells (A375), prostate carcinoma (DU145) and lung carcinoma (A549) cellswith IC values 20μg/ml. The symbiotic Streptomyces capillispiralis MTCC 10471 produces crude antibiotic30mg/Lt by using nonoptimized fermentation conditions. The structure of the antibiotic was explained by 1D,2D NMR and LC-ESI-MS/MS, MALDI-TOF/MS experiments, revealed that it belongs to cyclic ploy peptideActinomycin D