Biological synthesis and characterization of copper oxide nanoparticles using aqueous Psidium guajava leave extract and study of antibacterial activity of the copper oxide nanoparticles on Escherichia coli and Staphylococcus aureus

Nanobiotechnogy has been developed to synthesized copper oxide nanoparticle. This was carried out biologically using leaf extract of Psidium guajava as a reducing and stabilizing agent. Optical property showed a color change from dark brown to gold- yellow after the addition of leaf extract. The possible functional group in the plant extract responsible for the reduction of CuONps was identified as belonging to alkyl halide group by FT-IR analysis. UV- visible spectra of copper oxide nanoparticle showed a surface plasmon resonance peak at 390nm. The biologically synthesized copper nanoparticles were tested for antibacterial activity against two human pathogens viz, Escherichia coli and Staphylococcus aureus. Biosynthesized copper nanoparticle showed clear zone of inhibition or better activity against Escherichia coli and Staphylococcus aureus.