Chitosan Nanoparticles Loaded with Sideritis serrata Lag. Extract: A New Eco-Friendly Antifungal Agent for Sustainable Agriculture

Abstract

Fungal infections cause severe crop losses (15–60%) despite the use of antifungal agents, a problem exacerbated by climate change, population growth, and resistance. Regulatory restrictions on compounds like tebuconazole highlight the need for sustainable alternatives. This study evaluates the antifungal efficacy of chitosan nanoparticles loaded with Sideritis serrata extract (NPCH-SID) as an eco-friendly solution. The extract was obtained by freeze-drying and ethanol extraction, while NPCH-SID was synthesized via ionic gelation, achieving optimal size and encapsulation efficiency. In vitro assays revealed broad antifungal activity, with up to 156,140-fold improvement against Aspergillus brasiliensis compared to the free extract. Phytotoxicity tests on wheat seeds showed ~95% germination and enhanced root and shoot growth, confirming the safety and growth-promoting effect of this method. These findings position NPCH-SID as a promising tool for sustainable agriculture. Future work will assess its performance against additional pathogens under greenhouse and field conditions.