Biosynthesis of CuO-nanoparticles using extracts of Mespilus germanica, Crataegus spp., and Wild barberry and their synergistic antibacterial activity

The green synthesis of nanoparticles is gaining attention as a sustainable and eco-friendly alternative to conventional chemical methods. In this study, copper oxide nanoparticles (CuO-NPs) were biosynthesized using leaf extracts of Mespilus germanica (M-CuO), Wild barberry (B-CuO), and Crataegus spp. (C-CuO) as natural reducing and stabilizing agents. The synthesized nanoparticles were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and Field-emission scanning electron microscopy (FESEM). XRD results confirmed the formation of crystalline CuO with high purity. FESEM analysis revealed that the nanoparticles were nearly spherical with size ranges of 50-70 nm (M-CuO), 60-100 nm (B-CuO), and 50-80 nm (C-CuO). FTIR spectra indicated the presence of functional groups such as hydroxyl (-OH) and carbon-oxygen (C-O), along with characteristic Cu-O bond vibrations in the 500-700 cm-¹ range. The antibacterial activity of the CuO-NPs was tested against Gram-positive and Gram-negative bacteria, showing considerable inhibition. A synergistic effect was observed when combining the different types of CuO-NPs, resulting in enhanced antibacterial performance. These findings highlight the potential of plant-mediated CuO-NPs as promising candidates for biomedical and antibacterial applications.