BIOACTIVITY AND TAXONOMIC STUDIES OF NOCARDIOPSIS DASSONVILLEI AND NOCARDIOPSIS SPECIES FROM MARINE SEDIMENTS OF BAY OF BENGAL, INDIA

Globally, the outbreak of antibiotic-resistant pathogens derived infections urged an intensifying necessity for the survey of underexplored marine zone microorganisms for novel metabolites. Our current study emphasized on isolation, polyphasic characterization and bioactivity of the novel actinomycetes from the Bay of Bengal near Kakinada and Nizampatnam, Andhra Pradesh, India, which could provide lead bioactive compounds of therapeutic efficacy to repress the of pervasiveness multidrug-resistant pathogens. A total of fifteen actinobacterial strains (VJRM-1 to VJRM-15) were isolated and tested. Micro-morphological characteristics of the isolates were perceived by SEM (scanning electron microscope) analysis. Phylogenetic analyses of isolates were appraised with 16S rRNA gene sequence homology. The dendrogram was contrived by deploying the parsimony method in MEGA software version 6. Based on polyphasic studies, strains VJRM-7 and VJRM-8 identified as Nocardiopsis dassonvillei (KP299158) and Nocardiopsis sp (KP299159). In-vitro antimicrobial activity of crude ethyl acetate extracts derived from these strains revealed strong antagonistic activity against Gram-positive, Gram-negative bacteria and fungi. Both strains displayed positive results for the production of enzymatic activities. The morpho-physio-molecular and biological studies on moderate halophilic strains VJRM-7&VJRM-8 indicated as pre-eminent resources of bioactive compounds for medicinal and industrial uses in an eco-friendly manner for mankind.