Optimization of antimicrobial compound production by mangrove sediment derived Micromonospora sp. BSS-D-04 and Streptomyces sp. BSS-D-05 using response surface methodology.

In response to the growing global health crisis caused by antibiotic resistance, actinobacteria have emerged as a promising group of microorganisms capable of producing diverse and potent bioactive compounds. India's mangrove ecosystems, known for their rich microbial biodiversity, provide a unique habitat for discovering such novel organisms. In a previous study, two actinobacterial strains, Micromonospora sp. BSS-D-04 and Streptomyces sp. BSS-D-05 were isolated from the Bichitrapur mangrove sediments along the east coast of India and were found to exhibit broad-spectrum antibacterial activity against both Gram-positive and Gram-negative bacteria. The present study focused on optimizing the culture conditions for enhanced production of antimicrobial compounds using Response Surface Methodology (RSM). Among the tested carbon sources, glucose and sucrose significantly improved metabolite yields. Further the Central Composite Design (CCD) analysis identified pH 8.0, temperature 37 °C, and agitation speed 140 rpm as optimal growth parameters. Under these conditions, the antibacterial activity of the strains increased up to 122 %. These findings highlight the critical role of both nutritional and physical parameters in maximizing bioactive compound production. The optimized fermentation conditions established in this study holds promise for cost-effective and scalable antimicrobial development from indigenous mangrove-derived actinobacteria.