Green Synthesis Of Zinc Oxide Nanoparticles Using Plant Extracts For Antidiabetic Applications
Аннотация
Diabetes mellitus remains one of the foremost metabolic health crises globally, affecting over 537 million adults and demanding novel, safe, and efficacious therapeutic strategies. Zinc oxide nanoparticles (ZnO NPs) have attracted significant biomedical interest owing to their insulin-mimetic properties, carbohydrate enzyme inhibitory potential, and antioxidant capacity. Conventional chemical synthesis methods are hampered by toxicity and environmental concerns, whereas green synthesis exploiting plant phytochemistry offers a sustainable, eco-friendly, and biologically enriched alternative. The present study reports the systematic green synthesis of ZnO NPs using aqueous extracts of four medicinal plants Azadirachta indica, Aloe vera, Punica granatum, and Moringa oleifera across eight formulations (ZnO-F1 to ZnOF8) by modulating precursor concentration (0.05–0.1 M), extract-to-precursor ratio, and reaction pH (8–11). Nanoparticles were comprehensively characterized by UV-Vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), zeta potential analysis, thermogravimetric analysis (TGA), and Tauc plot bandgap determination. In vitro antidiabetic evaluation encompassed α-amylase and α-glucosidase inhibition, DPPH free radical scavenging, protein glycation inhibition, glucose uptake in L6 skeletal muscle cells (2-NBDG assay), and MTT cytotoxicity. The optimized formulation ZnO-F3 (Punica granatum extract, pH 11, 0.05 M) exhibited a crystallite size of 16.2 ± 1.2 nm, hydrodynamic diameter of 44.8 ± 2.3 nm, PDI of 0.192, zeta potential of −28.6 ± 0.9 mV, and optical bandgap of 3.46 eV. ZnO-F3 demonstrated superior α-glucosidase inhibitory potency (IC₅₀ = 42.3 ± 1.8 μg/mL) over the standard drug acarbose (IC₅₀ = 68.4 ± 2.1 μg/mL; p < 0.001), alongside potent DPPH scavenging (IC₅₀ = 78.4 μg/mL), antiglycation (IC₅₀ = 62.8 μg/mL), and 2.38-fold stimulation of glucose uptake. The findings substantiate the multifunctional antidiabetic potential of plant-extract-mediated ZnO NPs and provide a scientific basis for future translational research.