Searching for New Bioactive Metabolites from Marine Bacteria in the Persian Gulf: Antibacterial, Cytotoxic and Anti-inflammatory Agents

Natural products have historically been considered as a rich source of therapeutic agents and play a pivotal role in the development of medicinal compounds. Among microorganisms, marine bacteria have been recognized as a rich, promising and untapped resource. In the present work, we focused on Gram-positive bacterial population of Iranian coastal area of the Persian Gulf and study on bioactive potentials of the organic extracts from the isolates. The disc diffusion, DNA-interaction analysis along with MTT assay, and red blood cell hemolysis analysis were performed to evaluate antibacterial, cytotoxicity and anti-inflammatory activities of the extracts. We succeed to identify 6, 39, 34 and 21 novel bacterial producers of the bioactive metabolite having antibacterial, DNA interaction ability, cytotoxic activity, and anti-inflammatory effects, respectively. Approximately 15.4% of the isolates produced antibacterial agents against S. aureus and P. aeruginosa, meanwhile the Bacillus genus revealed the strongest potential. Moreover, a significant correlation was observed between DNA binding ability of the extracts and their cytotoxicity effect on cancerous cell lines; although the chemical nature of the solvent used effects on it. The data of anti-inflammatory study showed that some bacterial extractions are more potent than dexamethasone by more than 90% RBC hemolysis protection. Our results demonstrate that the Gram-positive bacterial population of the Persian Gulf can be considered as a novel rich source of bioactive compounds with valuable therapeutic impact.