Biochemical Evaluation of Green-Synthesized Silver Nanoparticles Derived from Waste Eriobotrya Japonica Seeds: Enzyme Inhibition and Antiglycation Potential

Silver nanoparticles were synthesized via a phytochemical-mediated green approach using waste Eriobotrya japonica seed extract as a natural reducing and stabilizing agent. This eco-friendly strategy eliminated the need for hazardous chemical reductants by utilizing bioactive phytochemicals present in the seed matrix. Nanoparticle formation was confirmed by ultraviolet-visible spectroscopy through a characteristic surface plasmon resonance band. Physicochemical characterization was performed using Fourier transform infrared spectroscopy, X-ray diffraction, dynamic light scattering, zeta potential analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The X-ray diffraction pattern displayed distinct reflections at 2θ values of 38.2°, 44.4°, 64.6°, and 77.5°, corresponding to the face-centered cubic crystalline structure of metallic silver, while peak broadening indicated nanoscale crystallite formation. Scanning electron microscopy revealed predominantly spherical nanoparticles with an average size of 13.52 nm. The zeta potential value of - 23.7 ± 7.50 mV suggested moderate colloidal stability and effective phytochemical surface stabilization. The biological activities of the synthesized nanoparticles were evaluated in comparison with the crude extract. The nanoparticles exhibited enhanced inhibitory effects against α-glucosidase and dipeptidyl peptidase-IV enzymes, along with notable antiglycation activity. The half-maximal inhibitory concentration for antiglycation was 11.04 µg/mL, substantially lower than that of the seed extract (164.9 µg/mL), indicating improved biofunctional performance following nanoparticle synthesis. These findings suggest that waste loquat seeds can be effectively converted into bioactive silver nanoparticles with potential relevance in antioxidant, antiglycation, and enzyme inhibitory applications. The present results are limited to in vitro evaluations, and the safety profile and underlying mechanisms remain to be clarified.