Microbial activity of manganese nanoparticles prepared using Citrus sinensis leaf extract

Abstract

The increasing demand for effective antimicrobial nanoparticles has led to the exploration of alternative approaches, including the use of plant extracts in the synthesis of metal nanoparticles. This study investigates the antimicrobial properties of orange leaf (Citrus sinensis) extract-mediated manganese nanoparticles. Green synthesis of manganese nanoparticles was done using the wet-impregnation method with orange leaf extracts and manganese nitrate. Characterization of MnNPs was done using Fourier transform infrared spectroscopy (FTIR), which confirmed the presence of stabilizing groups, including ester, ether, carbonyl, and hydroxyl groups, with peaks at 1100, 1200, 1350, 1500, 1800, and 3300 cm^-1. Scanning electron microscopy (SEM) revealed porous aggregates of MnNPs at 80 nanometers, while Electron dispersive spectroscopy confirmed the presence of a manganese atomic peak at 5.9 and 6.5 keV with a weight percentage of 91.31%, indicating successful synthesis. Antimicrobial analysis using the agar well diffusion method showed susceptibility of Pseudomonas aeruginosa and Escherichia coli (gram-negative bacteria) to MnNPs, with the highest activity observed against Aspergillus niger (fungi). In conclusion, orange leaf extract-mediated manganese nanoparticles exhibit significant antimicrobial activity, suggesting their potential as effective antimicrobial agents.