Resin-mediated green synthesis of CuO nanoparticles from Boswellia papyrifera: Comprehensive characterization and potent antibacterial and antioxidant properties

Abstract

Green synthesis of metal-oxide nanoparticles using plant extracts offers an environmentally benign, cost-effective route to functional nanomaterials. This study reports a facile room-temperature synthesis of CuO nanoparticles using resin extract of Boswellia papyrifera as the reducing and stabilizing agent, and evaluates their structural, antioxidant and antibacterial properties. CuO nanoparticles were prepared by reduction of copper (II) sulfate pentahydrate with the resin extract and characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) to confirm phase, surface functionalization and morphology. Antioxidant capacity was measured by the DPPH radical-scavenging assay (IC₅₀ values determined), and antibacterial activity of both the crude resin and biosynthesized CuO NPs was assessed by disk-diffusion assays against four pathogenic strains ( Staphylococcus aureus , Listeria monocytogenes , Escherichia coli , and Klebsiella pneumoniae ). FTIR, XRD and SEM analyses confirmed formation of CuO with a heterogeneous particle-size distribution and evidence of resin-derived surface capping. Both the resin extract and CuO NPs exhibited dose-dependent DPPH scavenging, while CuO NPs produced larger inhibition zones, particularly against Gram-positive strains, than the crude extract. These results indicate that B. papyrifera resin provides a simple green route to CuO nanoparticles with promising antioxidant and antibacterial potential for further applied development. • The study showcases a simple and eco-friendly method for synthesizing CuO nanoparticles at room temperature using the resin extract of Boswellia papyrifera . This green synthesis approach eliminates harmful chemicals, promoting sustainable nanomaterial production. • The synthesized CuO nanoparticles were thoroughly characterized using FTIR, XRD, and SEM. These analyses confirmed the successful formation of CuO nanoparticles, their phase integrity, and the presence of resin-derived surface functional groups, highlighting the significance of plant extracts in nanoparticle stabilization. • Both the resin extract and the biosynthesized CuO nanoparticles demonstrated strong antioxidant activity through DPPH radical-scavenging assays. Notably, the CuO nanoparticles exhibited greater antibacterial efficacy, particularly against Gram-positive bacteria such as Staphylococcus aureus , indicating their potential for therapeutic applications in combating bacterial infections.