From Sea to Science: Unveiling the Diverse Biotechnological Applications of Marine Endophytic Bacillus aerius

Marine endophytic bacteria are a promising source of bioactive compounds with diverse applications. This study investigated the multifunctional properties of Bacillus aerius PMRU2.8, isolated from the marine red alga Gracilaria sp. collected from the coastal region of Tamil Nadu, India. The bacterium demonstrated significant antimicrobial activity against multiple human pathogens, with its ethyl acetate extract containing bioactive compounds, including indoles and ketones. Molecular docking analysis revealed potential binding mechanisms of the compounds to bacterial proteins. Additionally, B. aerius efficiently synthesized silver nanoparticles (AgNPs) with enhanced antimicrobial efficacy compared with the crude extract. The bacterium also exhibited remarkable bioremediation capability, decolorizing up to 92.5% of the Direct Blue 6 azo dye within 48 h. Cytotoxicity assays confirmed the potential therapeutic applications of both the extract and the biosynthesized AgNPs. These findings highlight B. aerius as a valuable resource for pharmaceutical development, nanobiotechnology, and environmental remediation.