Biofabrication of nickel oxide nanoparticles from Pedalium Murex leaf extract: A promising approach for biomedical and environmental applications

Nanotechnology has become a rapidly progressing field in materials science due to the biosynthesis of nanoparticles (NPs) that has found numerous biomedical applications. The goal of this study was to use the methanolic leaf extract of Pedalium murex (MEPM) as a capping and bio-fabrication agent at room-temperature for the green biosynthesis of nickel metal nanoparticles (NiO-NPs). Pedalium murex has been widely used in complementary medicine. Characterization of the MEPM stabilized NiO-NPs was analyzed by UV-Vis, X-ray diffraction spectroscopy (XRD), Fourier-transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). Furthermore, the antioxidant and antibacterial properties of MEPM and NiO-NPs were studied. Biosynthesized NiO-NPs showed a lower total flavonoid and phenolic content than MEPM. Compared to MEPM, NiO-NPs (68%) showed superior antioxidant activity. The antimicrobial activity of the green synthesized NiO-NPs against Bacillus cereus, Streptococcus pyogenes, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and S. typhi was significantly higher than that of MEPM. Congo red (CR) and Rhodamine-B (Rh-B) dye degradation were used to evaluate the catalytic activity of the biosynthesized NPs. Maximum degradation efficiencies of 83% and 85% were observed for the CR and RhB dyes, respectively, both of which followed firstorder reaction kinetics. Generally, the biosynthesized NiO-NPs fabricated by MEPM showed excellent antioxidant and antibacterial efficacy. Therefore, the NiO-NPs is an eco-friendly, cost-effective, simple, and a promising approach for many biological applications.