Isolation, screening and production of bioactive compounds from marine Actinobacteria and studies on their biological activities

SUMMARY The improper usage of antibiotics results in the development of multidrug resistant microorganisms. Microorganisms alter their metabolism and genetic structure in order to resist antibiotic used against them. It is very difficult to treat this type of multidrug resistant microbes or we need new type of antibiotics or bioactive compounds to treat such pathogens. Hence, the demand for novel antibiotics continuously exists. Actinobacteria is a good source of many important bioactive compounds. Actinobacteria are filamentous, Gram-positive bacteria known for the production of more secondary metabolites. Actinobacteria are responsible for the most of the antibiotics in clinical use and they are consider as the most economically and biotechnologically valuable prokaryotes. The Streptomyces are member of actinomycetes, which produce bio-effective and functional metabolites, used as a broad spectrum in pharmaceutical including antihelminthic, antitumor, antimicrobial and antiviral agents. Actinobacteria produces about half of the discovered secondary metabolites. So far, the predominant exploited source to isolate Actinobacteria was the terrestrial soil. Antibiotics that are used during present day were derived from terrestrial Actinobacteria. The frequency of obtained novel bioactive compounds from terrestrial actinobacteria has been decreased over time. The greatest biodiversity found in the marine habitat than the terrestrial environment, as it covers about more than 70% of our planet?s surface. The life on the earth originated from sea and the variation in the chemical, biological and physical factors between terrestrial and marine environments, organisms existing in both environments are different. Thus, marine Actinomycetes are different from those of terrestrial counterparts, which may produce different types of bioactive compounds. Microbial diversity of marine sediment is little known, as it still not properly exploited. Hence, the chances for getting new actinobacteria and new antibiotics or biologically active substances are high in marine environment. Isolation of novel strains from marine actinobacteria could yield a broad spectrum of secondary metabolite. Further, no studies have been conducted in Gulf region to produce bioactive compounds from marine actinobacteria. Hence, this proposed study is aimed to isolate actinobacteria from marine habit, screening for their ability to produce bioactive compounds and studying their antioxidant, antimicrobial and other biological activities.