Green synthesis of copper oxide nanoparticles from Algerian propolis: Exploring biochemical, structural, antimicrobial, and anti-diabetic properties

Abstract

The green synthesis of nanoparticles (NPs) using natural extracts offers an eco-friendly alternative to traditional methods. In this study, we synthesized copper oxide nanoparticles (CuO NPs) using propolis extract as a natural reducing agent, resulting in two variants: CuO A and CuO B (calcined). UV-Vis spectroscopy confirmed successful synthesis, revealing distinct optical properties influenced by thermal treatment. Fourier transform infrared (FTIR) spectroscopy was performed to identify bioactive compounds stabilizing the NPs, with Cu-O stretching bands at 603 cm¹ for CuO A and at 633.6, 596.4, and 484.6 cmsup1; for CuO B. X-ray diffraction determined crystallite sizes of 68.5 nm (CuO A) and 74.82 nm (CuO B). Scanning electron microscopy showed spherical shapes for CuO A and star-shaped forms for CuO B. Biological assays revealed superior antioxidant activity for CuO A (IC50 = 0.027, AEAC = 2.01) compared to CuO B (IC50 = 0.052, AEAC = 1.76). CuO A also demonstrated higher total antioxidant capacity (TAC = 11.28 mg EAA/g NPs) and antimicrobial efficacy, with lower minimum inhibitory concentration (MIC = 5-10 mg·mL-1) than CuO B (MIC = 20-80 mg·mL-1). Its enhanced glucose absorption capacity highlights its potential antidiabetic applications. These findings underscore the superior biological properties of CuO A, demonstrating its promising biomedical potential.