Isolation and Characterization of Actinomycetes from Visakhapatnam Coast and Screening for Antimicrobial Activities of Actinomycetes against Pathogens

Abstract

Actinomycetes are one of the most attractive sources of antibiotics. In the present study, 32 isolates were isolated from marine soil sediments from the Bay of Bengal, Visakhapatnam. Isolation of Actinomycetes strain was obtained by serial dilution method and grown on actinomycetes isolation agar. Isolated strains were identified for their antibacterial activity of which only five isolates showed good result. They were evaluated for their inhibitory activity on 10 strains of microorganisms (Staphylococcus aureus (MTCC (Microbial Type Culture Collection) 3160), Bacillus subtilis (MTCC 441), Pseudomonas aeruginosa (MTCC 424), Bacillus cereus (MTCC 430), Proteus vulgaris (MTCC 426), Escherichia coli (MTCC 443), Saccharomyces cerevisiae (MTCC 170), Aspergillus niger (MTCC 961), Aspergillus flavus (MTCC 3396), Candida albicans (MTCC 227)). Antibacterial compounds were produced by submerged fermentation and their activity was checked against bacterial culture by antibiogram analysis where extracellular compounds showed positive result. Whereas KRBT-205, KRBT-401 and KRBT-411 showed antibiotic activity against all tested bacterial organisms, the zone of inhibition ranged from 10 mm to 24 mm and KRBT-103 and KRBT-401 showed antibiotic activity against all tested fungal organisms, the zone of inhibition ranged from 10 mm to 24 mm 10mm to 26 mm