Eco-friendly bacterial mediated synthesis, characterization and antimicrobial property of copper oxide nanoparticles Author: R. Elakkiya and C. Chandran P.G. and Research

Abstract

The present study investigated the isolation of a bacterial strain from agricultural soil and its application in thebiological synthesis of copper oxide nanoparticles (CuONPs). Soil samples were collected from cultivated agricultural fields in Orathanadu, Thanjavur District, Tamil Nadu, particularly from areas supporting leguminous plants. The bacterial isolate wasobtained using yeast extract mannitol agar and characterized by morphological, biochemical and molecular methods. The Bacillus haynesii cell-free supernatant (BHCFS) was used as a biological agent for CuONP synthesis. Addition of CFS tocopper acetate solution produced a colour change from blue to green, indicating nanoparticle formation. UV–visible spectroscopyshowed a characteristic absorption peak at 283 nm. FTIR analysis revealed hydroxyl, carboxyl, amine, aromatic and otherfunctional groups, suggesting the involvement of extracellular biomolecules in nanoparticle reduction and stabilization. Morphological analysis showed relatively small nanoparticles with an average size of 24.29 ± 5.68 nm. The synthesized CuONPs also exhibited antimicrobial activity against the tested microbial pathogens. Overall, the findings demonstrate that CFS can serve as an effective biological system for CuONP synthesis, providing an environmentally compatible approach withpotential antimicrobial applications.