Fabrication of biogenic silver nanoparticles using Bacillus vietnamensis JA01: characterization and antibacterial activity

The study of nanoparticles (NPs) had a great impact on their unique functional properties in various fields from engineering to biology. NPs, when employed in biology with advanced technology, have represented a milestone in biomedicine. In this study, we aimed to synthesize NPs from marine soil bacteria, considering the potential of the marine resources that are still under exploration and that have a role in nanotechnology. The intracellular synthesis of silver nanoparticles (AgNPs) was carried out using Bacillus vietnamensis isolated from marine soil. In this process, the nitrate reductase enzyme of the bacteria played a crucial role in reducing Ag⁺ to Ag⁰ and in the influence of the surface plasmon resonance effect which led to a color change after the reduction process. The confirmation of the presence or absence of the resultant AgNPs and their structural analyses were performed using UV–Vis, FTIR, XRD, FESEM, and EDAX. The synthesized AgNPs possess antimicrobial properties, and thus, we studied the antibacterial effect of the biosynthesized AgNPs against clinical pathogens such as Escherichia coli, Salmonella sp., Klebsiella sp., and Micrococcus flavus. These findings support the use of biosynthesized AgNPs from B. vietnamensis as antimicrobial agents in biotechnological approaches.