Synthesis of silver nanoparticles from marine bacteria and evaluation of antimicrobial, antifungal and cytotoxic effects

Background: Marine bacteria, a relatively untapped resource, have shown potential for synthesizing nanoparticles with distinct properties. Methods: The AgNPs were synthesized by using the marine bacteria Planococcus maritimus MBP-2 as a reducing and capping agent. The nanoparticles produced were characterized by UV–Vis spectroscopy, TEM and FTIR. The Planococcus maritimus MBP-2 synthesized AgNPs adhered antibacterial activity against selected both gram-negative and gram-positive bacteria such as Staphylococcus aureus, Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, and antifungal such Aspergillus niger, Aspergillus flavus, Penicillium commune and Penicillium digitatum. and the cytotoxic effect of Dalton's Lymphoma Ascites (DLA) cell lines. Results: The formation of AgNPs by bacteria was confirmed visually by a shift in color of the solution and the presence of UV-absorption maxima at 440 nm. The TEM images revealed spherical and cubic structures, with an average size of 24.9 nm. FTIR analysis confirmed the presence of some functional groups by showing peaks at 3330 and 1636 cm⁻¹. The AgNPs exhibited minimal antibacterial activity except P. aeruginosa. (11 mm). Whereas, inhibiting the growth of the fungi belonging to genus Aspergillus than to Penicillium. Also, in vitro cytotoxicity of AgNPs was evaluated using Dalton's Lymphoma Ascites (DLA) cell lines. The percentage of cell death was maximum (95.4 ± 2.16) at 20 µg/mL, indicating an excellent cytotoxic efficiency of AgNPs against DLA cells from the peritoneal cavity of the tumor-bearing mouse. Conclusion: This study suggests that Planococcus maritimus MBP-2 bacteria-mediated AgNPs can effectively be used as a potential biomedical agent.