Actinomycin "D" from Marine Sediment Associated Streptomyces Capillispiralis MTCC10471

In our screening program for new bio-active metabolites from marine actinomycetes, a cyclic depsipeptide was found in the fermentation medium of marine Strepromyces (SS23/4) isolated from sediments collected from Bay off Bengal, vellampattai,Tamilnadu. It showed strong biological activity against gram-positive / gram negative bacteria by agar overlay technique. It was taxonomically characterized by the basis of morphological and phenotypic characteristics, genotypic data and phylogenetic showing Streptomyces sps. Bio active compound was obtained by solvent extraction and purification using column chromatography followed by reverse phase HPLC. The pure compound had potent activity against Mycobacterium tuberculosis and Multi Drug Resistant Mycobacterium tuberculosis strains (437RU) at a concentration of 10 μg/mL, and The minimum inhibitory concentration (MIC) against standard test organisms was found to be 1μg/mL against B.subtilis, E.coli and Methicillin resistant Staphylococcus aureus. The compound exhibited potent cytotoxic activity against breast carcinoma (MCF-7), melanoma cells (A375), prostate carcinoma (DU145) and lung carcinoma (A549) cells with IC values 20μg/ml. The symbiotic Streptomyces capillispiralis MTCC 10471 produces crude antibiotic 30mg/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 peptide Actinomycin D.