Green Synthesis and Characterization of Zinc Oxide Nanoparticles Using Cyperus pangorei Grass Extract and its Antibacterial Activity

Green synthesis of nanoparticles using plant-derived biomolecules has emerged as an eco-friendly and sustainable approach in nanobiotechnology. In the present study, zinc oxide nanoparticles (ZnO NPs) were biosynthesized using aqueous leaf extract of Cyperus pangorei, a biologically important grass species rich in phytochemicals such as flavonoids, phenolics, alkaloids, and terpenoids that act as natural reducing and stabilizing agents. UV–Visible spectroscopy confirmed nanoparticle formation with a characteristic absorption peak at 264 nm, while FTIR analysis revealed the involvement of hydroxyl, amine, phenolic, and flavonoid functional groups in nanoparticle stabilization. XRD studies confirmed the crystalline nature of ZnO nanoparticles, and SEM analysis demonstrated predominantly spherical particles with sizes below 30 nm. The biosynthesized ZnO nanoparticles exhibited significant antibacterial activity against important human pathogens including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella sp., indicating broad-spectrum antimicrobial potential against both Gram-positive and Gram-negative bacteria. Furthermore, the nanoparticles showed promising antioxidant and agricultural properties by enhancing plant growth and reducing environmental stress effects in crop plants. The use of Cyperus pangorei, an abundantly available dry grass species with rich bioactive constituents, highlights its biological significance as a sustainable resource for green nanomaterial synthesis. The study demonstrates that Cyperus pangorei-mediated ZnO nanoparticles are eco-friendly, cost-effective, and biologically active nanomaterials with potential applications in biomedical, agricultural, and agro-biotechnological fields.