Green Synthesis of Copper Oxide Nanoparticles Using Syzygium Cumini Seed Extract and Its Antioxidant and Antibacterial Activity

In this study, biosynthesis of copper oxide nanoparticles with new approach to enhanced the Antimicrobial properties against gram-negative and gram-positive and the antioxidant activity were performed by use of a new type of plant extract, Syzygium cumini seed, in an environmentally friendly, cost-effective, simple procedure way by adding CuSO4 to aqueous Syzygium cumini seed extract followed by stirring. The resulted solution was heated at 40–45°C and CuONPs were synthesized. Disc diffusion method was applied to evaluation the Antimicrobial properties of the extract and nanoparticles towards resistance into Klebsiella (gramnegative) and Staphylococcus (gram-positive). DPPH assay was performed to evaluation the antioxidant activity. X-ray diffraction pattern result showed characteristic peaks of CuO that demonstrated a successful formation of pure crystalline CuONPs. In the Fourier transform infrared spectroscopy, there are two bands in the 609 cm–1 and 451 cm–1 which is corresponded to CuO. Also, a negative potential value around –10 mV obtained by Zeta potential analysis. Energydispersive X-ray spectroscopy analysis showed strong peaks for Cu and O, support supposition of CuONPs. Scanning Electron Microscope images indicated polydispersed spherical rounded particles with the size of average 42–90 nm. Antibacterial tests showed effective diameter about 6 and 2 mm for CuONPs against Klebsiella and Staphylococcus in agar disc diffusion method, respectively. DPPH assay found CuONPs to possess effective antioxidant properties when compared to ascorbic acid at all the concentrations tested. Biosynthesized CuONPs exhibited an excellent antibacterial and antioxidant activity against Gram-negative and Gram-positive bacteria and DPPH free radical, respectively. Hence, the CuONPs are expected to be used in future for effective biomedical applications.