Green Synthesis of Silver Nanoparticles with Hyssopus officinalis and Salvia officinalis Extracts, Their Properties, and Antifungal Activity on Fusarium spp.

Recent focus has been given to nanoparticles as an alternative fungicidal compound instead of chemical ones. More environmentally friendly ways of synthesis are the highest priority regarding the antifungal agents in the agriculture sector. Therefore, in this research, hyssop ( H. officinalis ) and sage ( S. officinalis ) aqueous extracts were prepared and used as a reducing source in the green synthesis of silver nanoparticles (AgNPs). Aqueous extracts and green synthesized AgNPs were examined for phytochemical composition and antioxidant capacity. Hyssop and sage extracts based AgNPs were analyzed using UV-vis spectrometry, SEM-EDS, and TEM-EDS. Antifungal activity against Fusarium spp. isolates collected from different infected crops was determined. Fusarium spp. isolates from strawberry, asparagus, pea, carrot, wheat, and rapeseed samples identified at the molecular level by translation elongation factor 1-alpha (TEF1α) gene amplification and sequencing. Green synthesized AgNPs had lower phytochemical content, however higher antioxidant activity compared to pure extracts. Both hyssop and sage extracts are suitable reducing agents for AgNPs formation, and sage extract results in larger particle size. Aqueous hyssop extract had higher antifungal activity than aqueous sage extract. However, a 10% concentration of whole sage extract based AgNPs solution, added to the PDA medium, and a 5% concentration of hyssop extract based AgNPs inhibited Fusarium spp. the most. F. proliferatum was the most sensitive to all treatments among the other fungi.