Antioxidant and cytoprotective effects of Ifloga spicata-derived gold nanoparticles in human lymphocytes

Green synthesis of gold nanoparticles (AuNPs) using plant extracts has emerged as a sustainable and biocompatible approach in nanomedicine. In this study, AuNPs were synthesized using Ifloga spicata (Forssk.) whole-plant extract and evaluated for their biological effects on human blood lymphocytes exposed to hydrogen peroxide–induced oxidative stress. Nanoparticle formation was confirmed using UV–visible spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). Exposure to oxidative stress significantly increased intracellular reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS), while suppressing antioxidant enzyme activities, including catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD). Treatment with I. spicata–mediated AuNPs significantly attenuated ROS and TBARS levels and restored antioxidant enzyme activities in a concentration-dependent manner, with maximal protective effects observed at 5 and 50 µg/mL. Importantly, AuNPs did not induce adverse oxidative effects under normal physiological conditions, indicating a favorable cytocompatibility profile. These findings suggest that I. spicata–derived AuNPs exhibit antioxidant and cytoprotective properties and may represent promising candidates for mitigating oxidative stress–related cellular damage. Further in vivo studies are warranted to elucidate their mechanistic pathways and therapeutic potential.