Green synthesis of iron oxide nanoparticles using Gomphostemma mastersii leaf extract and evaluation of structural antioxidant and antimicrobial properties

Abstract The purpose of this work is to demonstrate the eco-friendly production of iron oxide nanoparticles (FeONPs) by using Gomphostemma mastersii leaf extract as a capping and stabilizing agent for the first time. This study uses a microwave-assisted method and the synthesized FeONPs were characterized using different techniques, and were subsequently assessed for their antimicrobial, antifungal, and antioxidant properties. The synthesized FeONPs exhibited substantial free radical scavenging activity, with an IC50 value of 174.52 ± 2.38 µg/ml and a FRAP value of 346.86 ± 6.57 µM AAE/g. Additionally, the FeONPs displayed antimicrobial activity against bacterial ( E. coli and B. subtilis ) and fungal strain ( A. niger and S. commune ). The highest and lowest antibacterial activity was observed against B. cereus (14.84 mm) and Salmonella spp. (12.73 mm), respectively. The current work therefore verified the antibacterial, antimicrobial, and antioxidant qualities of the green nanoparticles that were synthesized from G. mastersii. Green synthesis of nanoparticles using plant extracts has emerged as an eco-friendly and cost-effective alternative to conventional methods. Plant phytochemicals act as natural reducing and stabilizing agents, enhancing the biological functionality of nanoparticles. Iron oxide nanoparticles are widely studied for their biomedical and antimicrobial applications; however, the use of novel plant sources and rapid synthesis techniques remains limited. The aim of this study is to synthesize iron oxide nanoparticles using Gomphostemma mastersii leaf extract through a microwave-assisted green method, characterize their physicochemical properties, and evaluate their antioxidant and antimicrobial activities for potential biomedical applications.