Antimicrobial, Antioxidant and Cytotoxic Activity of Marine Streptomyces MS-60 Isolated from Bay of Bengal

A. Zarina, Anima Nanda

Abstract: The main aim of the study was to evaluate the antimicrobial, antioxidant and cytotoxic potential of crude extract of Marine Streptomyces species isolated from soil of Chennai coast, Tamilnadu. Primary and Secondary screening for antimicrobial activity was determined by Cross streak method and Agar well diffusion method respectively. Gram positive bacteria were found most sensitive to the actinomycetes isolate MS-60 in both primary and secondary screening. The actinomycete isolate was identified as a species of the genus Streptomyces on the basis of microscopic and biochemical characteristics. The compounds present within the crude extract of Marine Streptomyces MS-60 showed maximum antimicrobial activity against Streptococcus mutans (34mm), and minimum activity against Klebsiella pneumonia (13 mm). Antioxidant activity of the crude extract of MS-60 was tested by 1, 1-Diphenyl-pircrylhydrazyl (DPPH) free radical scavenging assay and it exhibit potent scavenging activity at (Ic5012 g/ml). The anticancer activity of the secondary metabolite of actinomycetes was evaluated on HT-29 (Human colon cancer cell) line by 3- (4, 5-dimethylthiazol-2-yl) -2, 5-diphenyltetrazolium bromide (MTT) assay. The in vitro cytotoxicity assay on Human colon cancer cell line [HT-29] revealed that the secondary metabolite had the strongest cytotoxicity with Ic50 26.5g/ml.

Keywords: Marine Streptomyces sp, Antimicrobial activity, Antioxidant activity, MTT, Cytotoxicity