Biosynthesis and characterization of iron oxide nanoparticles fabricated using cell-free supernatant of Pseudomonas fluorescens for antibacterial, antifungal, antioxidant, and photocatalytic applications
摘要
This study investigates the biosynthesis of iron oxide nanoparticles (Fe2O3NPs) using the cell-free supernatant of Pseudomonas fluorescens. The synthesized Fe2O3NPs were characterized through UV–VIS, XRD, FTIR, FESEM, EDX, TEM, BET, and VSM analyses. The XRD results confirmed that Fe2O3NPs were successfully synthesized and EDX analysis indicated that iron accounted for 89.5% of the sample composition. Imaging via SEM and TEM revealed average diameters of 20.43 ± 5.38 nm and 24.32 ± 5.03 nm, respectively. The antimicrobial effects of Fe2O3NPs were assessed against four bacterial strains and four fungal species. Inhibition zones of 8.35 ± 0.103 mm and 8.31 ± 0.128 mm were observed for Pseudomonas syringae and Staphylococcus aureus at a concentration of 400 μg mL−1 of Fe2O3NPs. Antifungal efficacy showed growth rate reductions of 90.4% for Aspergillus niger, 71.1% for Monilinia fructigena, 68.8% for Botrytis cinerea, and 84.2% for Penicillium expansum, compared to controls. The nanoparticles demonstrated photocatalytic degradation efficiencies of 89.93%, 84.81%, and 79.71% for methyl violet, methyl orange, and methylene blue, respectively. Also Fe2O3NPs exhibited significant DPPH free radical scavenger activity with an IC50 value of 8.45 ± 0.59 μg mL−1. The study’s findings underscored the significant potential of Fe2O3NPs in addressing environmental pollution and combating pathogenic microorganisms.