Isolation and characterization of pigmented bacteria showing antimicrobial activity from Malaysian marine environment

ABSTRACT

Aims: Natural products play a prominent role in the discovery of leads for the development of drugs in the treatment of human diseases. Much of nature remains to be explored, especially marine and microbial environments. Methodology and results: Fifty-five pigmented marine bacteria were isolated from sponges, seawater, mangrove sediment, sea cucumber and mussel from different coastal area of Malaysia. The antimicrobial activities of these bacteria were investigated by disk diffusion method against pathogenic bacteria. Out of 55 isolates, 18 isolates exhibited antimicrobial activity, which based on morphological characterization, 53% of them were Gram positive and 47% were Gram negative. All active isolates were able to tolerate more than 4% NaCl in the nutrient agar medium that indicated they were autochthonous to marine environment and moderate salt tolerant in nature. Molecular identification of isolates by the strong antimicrobial activities indicates that isolates WPRA3 (JX020764) and SM11-3j belong to genus Serratia and isolate SDPM1 (JQ083392) belongs to genus Zooshikella. Conclusion, significance and impact of study The results of present study revealed that the active isolates are potential producer of antimicrobial secondary metabolites and might be utilized as drug candidate