Rapid synthesis of magnetic FeO/Ag nanocomposite based on a plant-mediated approach and its biological activity.

The present study described a quick, efficient, and eco-friendly method for producing FeO-Ag nanocomposite (NC) using Mentha pulegium L. plant extract. Ultrasonic-assisted extraction (UAE) was employed to prepare an aqueous extract due to its speed and effectiveness. During the manufacture of FeO-Ag NC, the prepared plant extracts were utilized as naturally occurring stabilizing precursors. The study also employed several methods for characterizing the synthesized NC, including X-ray diffraction patterns, which estimated the mean particle size to be 52 nm using the Deby-Scherrer equation. The successful synthesis of FeO-Ag NC was approved by a broad absorption band from 400 to 425 nm in the absorption spectrum. Subsequently, the samples' antibacterial, antifungal, and antioxidant potentials (FeO NPs, Ag NPs, FeO-Ag NC, and the extract) were investigated. Notably, the NP and NC samples showed higher antibacterial activity than the extract, wherein gram-negative bacteria were more significantly affected than gram-positive bacteria. The FeO-Ag NC had MIC values of 0.062 mg/mL against Staphylococcus aureus and Escherichia coli. The FeO-Ag NC was found to have a significant detrimental impact on the bacterial membranes of E. coli and S. aureus, as evidenced by the quick release of cytoplasmic components such as protein, nucleic acid, and potassium. The results also showed that the extract and FeO-Ag NC samples exhibited strong antioxidant activity. The study recommends further investigation on the application of these metal nanoparticles in the water remediation, agriculture, and food industries due to their strong biological activity.