The Utilization of Curcumin in the Environmentally Friendly Green Synthesis of Zinc Oxide-Curcumin Nanoparticles and Their Antibacterial Activity

Abstract

In this study, Curcumin (Cur) was utilized as a green reducing and capping agent for the synthesis of zinc oxide-curcumin (ZnO/Cur) nanoparticles (NPs) via an eco-friendly approach. The physicochemical properties of the synthesized nanocomposites were systematically characterized using UV-visible spectrophotometry, X-ray diffraction (XRD), and field-emission scanning electron microscopy (FESEM). UV-Vis analysis confirmed the successful formation of ZnO/Cur NPs, exhibiting a characteristic absorption peak at 377 nm, which falls within the typical range for ZnO nanoparticles (330–460 nm). XRD analysis revealed the hexagonal wurtzite crystalline structure of ZnO with a crystallite size of approximately 23.6 nm. FESEM images demonstrated that the nanoparticles possessed a spherical to hexagonal morphology with particle sizes ranging from 50.06 to 86.78 nm. The antibacterial efficacy of ZnO/Cur NPs was evaluated against Staphylococcus aureus (Gram-positive) and Moraxella species (Gram-negative) using the agar disk diffusion method. The nanocomposites exhibited significant antibacterial activity, with inhibition zones of 24 mm and 22 mm against S. aureus and Moraxella sp., respectively, at a concentration of 1000 μg/mL. The results suggest a synergistic antibacterial effect between ZnO and Curcumin, attributed to reactive oxygen species (ROS) generation and cell membrane disruption. These findings highlight the potential of ZnO/Cur NPs as promising antibacterial agents for biomedical and environmental applications.