Green Tea (camellia Sinensis) Mediated Synthesis of Zinc Oxide (zno) Nanoparticles and Studies on Their Antimicrobial Activities

Green synthesis of Zinc oxide nanoparticles (ZnO Nps) was carried out using the aqueous extract of green tea (Camellia sinensis) leaves. The UV-Vis spectrum was recorded to monitor the formation of the nanoparticles, which exhibited a blue shifted absorption peak at 325 nm. The XRD pattern revealed well-defined peaks appearing at 2θ positions corresponding to the hexagonal wurtzite structure of ZnO nanoparticles. The average size of the nanoparticles calculated using XRD data was 16 nm. FT-IR spectra were recorded for the green tea extract and for the ZnO nanoparticles to identify the biomolecules involved in the synthesis process. The higher percentage of phenolic compounds, with antioxidant potential, provided the reducing action on the metal oxides and significantly present amino acid, protein and lipids helped to stabilize the growth of the nanoparticles. Agar well -diffusion method was used to study the antibacterial and antifungal activities on selected pathogenic species. The synthesized ZnO Nps showed better and comparable antimicrobial activities with respect to the activities of synthetic drugs.