Investigation of the Biological Applications of Biosynthesized Nickel Oxide Nanoparticles Mediated by <i>Buxus wallichiana</i> Extract

The preparation of nickel oxide nanoparticles (NiO NPs) was carried out using an environmentally friendly and novel green synthetic strategy that included the use of Buxus wallichiana leaf extract as a reducing agent. Energy-dispersive X-ray (EDX), Fourier-transform infrared spectroscopy (FTIR), diffuse reflectance spectroscopy (DRS), X-ray diffraction (XRD), scanning electron microscope (SEM), and thermogravimetric analysis (TGA) techniques were used to characterize the resulting NiO NPs. At various concentrations, NiO NPs were tested for their percentage scavenging activity against the ABTS (2,2 '-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) free radical, with an IC50 value of 234.84 g/L. Furthermore, the bactericidal activity of NiO NPs was studied by the agar well diffusion method against two Gram-positive bacterial strains (B. licheniformis and B. subtilis) and two Gram-negative bacterial strains (E. coli and K. pneumoniae).