Green synthesis and antioxidant evaluation of calcium oxide nanoparticles using Syzygium cumini fruit extract: An in vitro study

The lack of safe, cost-effective, and eco-friendly antioxidant agents to combat oxidative stress–induced chronic diseases remains a significant challenge in biomedical research. Green synthesis offers a sustainable approach for producing bioactive nanoparticles using plant-derived phytochemicals. In this study, calcium oxide nanoparticles (CaO NPs) were synthesized using Syzygium cumin fruit extract. The formation of nanoparticles was confirmed by UV–Visible spectroscopy, while X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR) revealed crystalline, spherical nanoparticles stabilized by phytochemical capping. The antioxidant activity of the synthesized CaO NPs was evaluated using DPPH, FRAP, ABTS, hydrogen peroxide, and nitric oxide assays at concentrations ranging from 10–50 µg/mL. The nanoparticles exhibited strong, concentration-dependent radical scavenging activity comparable to ascorbic acid. Data shows the potential of S. cumin-mediated CaO NPs as promising candidates for biomedical applications targeting oxidative stress. Thus, we show that Syzygium cumini–mediated green synthesis can produce structurally stable CaO nanoparticles with significant antioxidant activity, thereby contributing to the development of eco-friendly nanomaterials for oxidative stress–related biomedical applications.