Green synthesis of Ag–Fe₂O₃ nanocomposite using Adiantum venustum D. Don. extract and evaluation of its antimicrobial and antioxidant properties

Abstract

Green synthesis of metal oxide nanoparticles and nanocomposites has emerged as an eco-friendly alternative to conventional nanomaterial fabrication methods due to reduced chemical toxicity and improved biological compatibility. In the present study, Adiantum venustum D. Don extract was used for the green synthesis of an Ag–Fe2O3 nanocomposite, followed by physicochemical characterization and evaluation of antimicrobial and antioxidant activities. Synthesized nanocomposite was analyzed by Fourier transform infrared (FTIR), X-ray diffraction (XRD), Scanning electron microscopy and energy dispersive X-ray (SEM-EDX), Dynamic light scattering (DLS) and Zeta potential analysis. FTIR analysis confirmed the involvement of plant-derived functional groups in the reduction and stabilization of the nanocomposite, and XRD analysis confirmed the formation of crystalline α-Fe2O3 and the presence of diffraction peaks related to Ag. The SEM analysis revealed predominantly spherical nanoparticles with limited aggregation, while the EDX analysis confirmed the presence of Fe, O, and Ag. The synthesized nanocomposite showed concentration-dependent antibacterial properties against S. aureus (33.00 ± 0.50 mm) and E. coli (21.00 ± 0.60 mm) at a concentration of 1.0 mg/mL. MIC values were 0.25 mg/mL for S. aureus and 1.50 mg/mL for E. coli. Furthermore, antifungal activity against Fusarium oxysporum and high antioxidant activity in DPPH and FRAP assays were also observed. The improved biological activity of the Ag–Fe2O3 nanocomposite can be attributed to the synergistic effect of the incorporation of silver, the reactivity of the Fe2O3 surface, generation of reactive oxygen species, and phytochemical-assisted stabilization of the surface. The results indicate that the green synthesized Ag–Fe2O3 nanocomposite has potential biomedical applications. Clinical trial Not applicable