Biosynthesis and antibacterial activity of selenium nanoparticles using Pseudomonas aeruginosa and Bacillus pumilus RMO6.

Bacterial infections are common and challenging to treat due to increasing antibiotic resistance. Research has focused on using various nanoparticles, with studies showing that Selenium Nanoparticles (Se-NPs) have antibacterial effects. This study focuses on the biosynthesis and characterization of Se-NPs using Pseudomonas aeruginosa and Bacillus pumilus RMO6. Bacteria were cultivated on the microbial culture media, followed by the synthesis of Se-NPs through the reduction of sodium selenite in the bacterial supernatant. Characterization techniques, including UV-Vis spectroscopy, FT-IR, XRD, TEM imaging, and DLS, confirmed the successful formation of Se-NPs, revealing their size, morphology, and surface properties. The Biosynthesized nanoparticles exhibited significant antimicrobial activity against four standard bacterial strains: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis. Notably, Se-NPs synthesized by Bacillus pumilus demonstrated a significantly lower MIC and greater effectiveness in biofilm eradication (MBEC) compared to those produced by Pseudomonas aeruginosa, with a fourfold reduction in MIC against Escherichia coli and Staphylococcus aureus. These findings highlight the potential of Se-NPs as effective agents in combating resistant bacterial infections and suggest their promising application in medical treatments.