Green synthesis of Superparamagnetic Iron Oxide and Silver Nanoparticles in Satureja hortensis Leave Extract: Evaluation of Antifungal Effects on Botryosphaeriaceae Species.

In recent years, green synthesis methods of metallic nanoparticles (MNPs) have been attractive because of the more facile, cheaper, and appropriate features associated with biomolecules in MNPs biosynthesis. This research represented an easy, fast, and environmentally friendly method to biosynthesis of superparamagnetic iron oxide nanoparticles (SPIONPs) and silver nanoparticles (AgNPs) by the Satureja hortensis leaf extract as stabilizer and reducer. The SPIONPs synthesized in co-precipitation method. The biosynthesized SPIONPs and AgNPs were studied their antifungal effects against three Botryosphaeriaceae plant pathogens, Botryosphaeria dothidea, Diplodia seriata, and Neofusicoccum parvum. UV-visible spectra (UV-Vis), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), field emission scanning electron microscopy (Fe-SEM), energy-dispersive X-ray spectroscopy (EDX), and vibrating-sample magnetometer (VSM) analyses were used to evaluate the physicochemical properties and verify the formation of green synthesized SPIONPs and AgNPs. UV-Vis spectra revealed absorption peaks at 243 and 448 nm for SPIONs and 436 nm for AgNPs, respectively. Microscopic and XRD analysis showed that SPIONPs and AgNPs was found spherical in shape with an average particle size of SPIONPs and AgNPs 10 and 12 nm, respectively. The antifungal test against Botryosphaeriaceae species showed that SPIONPs and AgNPs possess antifungal properties against B. dothidea, D. seriata, and N. parvum. However, AgNPs exhibits greater antifungal activity than SPIONPs. The results of the cytotoxicity tests of SPIONs and AgNPs on the MCF-7 cell line showed that AgNPs was significantly more cytotoxic towards the MCF-7 cell line, whereas no significant cytotoxic effect was recorded by SPIONs. Therefore, these biosynthesized MNPs could be substituted for toxic fungicides that are extensively applied in agriculture and contribute to environmental health and food safety.