This study investigated the green synthesis of Fe₃O₄ nanoparticles and their nanocomposites (Fe₃O₄/MgO and Fe₃O₄/MgO/CaP) using Sidr leaf extract as an environmentally friendly and sustainable approach. The aim was to evaluate their antibacterial activity and explore their potential applications in agriculture. The synthesized materials were characterized using UV-Visible spectroscopy, FTIR, XRD and SEM analyses. SEM results showed that Fe₃O₄ nanoparticles had particle sizes ranging from 77.71- 89.55 nm, while Fe₃O₄/MgO exhibited smaller sizes of 61.82-82.42 nm, and Fe₃O₄/MgO/CaP showed a broader distribution between approximately 52.53-93.30 nm. The antibacterial activity was assessed using the agar well diffusion method against Staphylococcus aureus and Pseudomonas aeruginosa at concentrations of 50, 100, and 200 mg/L. The results showed that none of the synthesized nanoparticles or nanocomposites produced inhibitory effects against either bacterial strain at the tested concentrations. In contrast, the plant extract demonstrated antibacterial activity against Staphylococcus aureus, while no effect was observed against Pseudomonas aeruginosa. The agricultural performance of the nanomaterials was evaluated through seed germination and early growth parameters, including germination percentage, root number, root length, and shoot length. The results indicated that nanoparticle treatments improved plant growth compared to the control. In conclusion, the findings suggest that although the synthesized nanomaterials did not exhibit antibacterial activity under the tested conditions, they show potential as growth-promoting agents in agricultural applications.
