Green Synthesized CuO Nanoparticles Using <i>Zanthoxylum chalybeum</i> Extracts: Characterization and Antibacterial Effects

Abstract

The green synthesis of metal oxide nanoparticles via plant extracts is an environmentally friendly, simple, inexpensive, and rapid, method for synthesizing nanoparticles for biological applications. In this study, Zanthoxylum chalybeum bark extracts were used to explore the biosynthesis of copper oxide nanoparticles (CuO NPs). The CuO NPs were successfully synthesized from an aqueous extract of Zanthoxylum chalybeum stem bark and characterized. The morphological, optical, and structural characteristics of the nanoparticles were assessed via scanning electron microscopy (SEM), X-ray diffraction (XRD), UV‒visible spectrophotometer, and Fourier transform infrared (FTIR) spectroscopy. Nanocrystalline CuO NPs, with an average crystalline size of 18.26 nm and a band gap energy of 1.45 eV, were confirmed via XRD and UV‒vis spectrophotometry, respectively. The SPR (surface plasmon resonance) peak was identified at wavelength of 529 nm in the UV-Vis spectrum. FT-IR analysis confirmed the presence of various functional groups that trigger the synthesis of CuO NPs. Morphological studies via SEM revealed spherical nanoparticles. Antifungal evaluation of the Candida albicans fungal strain and antibacterial evaluation of four bacterial strains ( Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa ) revealed greater potency of the green-synthesized CuO NPs than the Zanthoxylum chlamydium extracts and erythromycin (positive control). The green-synthesized CuO NPs obtained may be used as an antibacterial and antifungal agent for various therapeutic uses in medicine.