Isolation, Identification and Characterization of marine bacteria from the deep sea sediment of Bay of Bengal, India, and their antimicrobial and cytotoxicity potential.

A total of 108 marine bacteria were isolated from the deep sea sediment of Bay of Bengal, India. Of which, 15 bacteria showed antimicrobial activity against human pathogenic bacteria. These antagonistic marine bacteria were characterized phenotypically and their taxonomic affiliations were made on the basis of 16S rRNA gene homology and molecular phylogeny tree analysis, the antagonistic marine bacteria were identified as the species of Bacillus, Halobacillus, Staphylococcus, Marinobacter. The extracts of potent marine bacteria exhibited differential cytotoxicity towards lung (A549), cervical (HeLa), breast (MCF-7) and colon (HT-29) cancer cells. The acridine-orange and ethidium bromide (AO/EB) staining of the extract of strain MB30-treated cancer cells showed typical characteristics of apoptosis such as nuclear condensation, cell shrinkage and formation of apoptotic bodies. Present investigation, reports potent marine bacteria from the deep sea sediment of Bay of Bengal that exhibit broad-spectrum antimicrobial and cytotoxicity potential. Due to their innate bioactive potential, these bacteria can be used as the source of potent molecules.