Green Synthesis of Copper, Iron and Silver Nanoparticles from Origanum vulgare L. subsp. vulgare; Characterization, In Vitro Enzyme Inhibition, Antimicrobial Activities and In Silico Molecular Docking Studies.

This study revealed the characteristics of the ethanol extract of Origanum vulgare L. subsp. vulgare, copper, iron, and silver nanoparticles (CuNPs, FeNPs, AgNPs) were synthesized with the extracts for the first time. The NPs were characterized using field emission scanning electron microscopes (FE-SEM), field emission scanning electron microscope-energy-dispersive X-ray analysis (FESEM-EDX), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR). UV-Vis spectrophotometry is used for the confirmation of NPs. The extract had bioactive components, including thymol (35.99%) and naringenin (41.02 µg/g). Molecular docking of thymol/naringenin-AgNPs complexes with the PapR7 C-terminus produced MolDock scores of - 122.545 and - 94.929 for naringenin-AgNPs and thymol-AgNPs. AgNPs and CuNPs exhibited potent antibacterial activity against Bacillus cereus, Staphylococcus aureus, and Pseudomonas aeruginosa. AgNPs exhibited protease activity (5 mg/mL), and CuNPs exhibited lipase activity (5 and 10 mg/mL). FeNPs exhibited weak inhibitory properties (IC50 > 9 mg/mL) and did not show any detectable enzymatic activity.