Marine actinobacterial metabolites: Current status and future perspectives

Marine actinobacteriology is one of the major emerging areas of research in tropics. Marine actinobacteria are the most economically as well as biotechnologically valuable prokaryotes. Many representatives of the order Actinomycetales are prolific producers of thousands of biologically active secondary metabolites. Among the actinobacteria, streptomycetes group are considered economically important because out of the approximately more than 10,000 known antibiotics, 50–55% are produced by this genus. The ecological role of actinobacteria in the marine ecosystem is largely neglected and various assumptions meant there was little incentive to isolate marine strains for search and discovery of new drugs. The search for and discovery of novel actinobacteria are of significant interest to drug discovery due to a growing need for the development of new and potent therapeutic agents. In this review an evaluation is made on the present state of research on marine actinobacterial metabolites and its perspectives. The highlights include the production and biotechnological applications of metabolites such as antibiotics, anticancer compounds, melanins, enzymes and enzyme inhibitors, single cell protein and as probiotics in aquaculture. With increasing advancement in science and technology, there would be greater demands in future for new bioactive compounds synthesized by actinobacteria from various marine sources.