Peptide-based inhibition of Fusarium graminearum: a molecular study of bioactive compounds from okara protein

Agri-food by-products are gaining increasing attention as sustainable sources of bioactive compounds for plant protection. Okara, the insoluble residue from soybean (Glycine max) processing, is particularly promising due to its high protein content and widespread availability. This study investigates the antifungal potential of peptides derived from okara proteins against Fusarium graminearum, a major plant pathogen of growing concern under climate change. An optimized, sustainable protocol was used to efficiently extract proteins, maximizing yields by overcoming specific matrix effects. Enzymatic hydrolysis was then performed, followed by peptide fractionation to reduce complexity, enabling targeted bioactivity investigation. Peptides from each fraction were characterized and identified by mass spectrometry. An in silico analysis was performed on the identified peptide, using different specific database tools to link structural features to potential bioactivity to define the antifungal bioactivity. This computational approach aimed to support the interpretation of experimental data and the selection of promising candidates. By integrating biochemical analyses with bioinformatic tools, this work supports the identification and valorization of bioactive peptides from agro-industrial residues. The results contribute to the development of natural, peptide-based strategies for sustainable plant disease management, in line with circular economy principles and the urgent need for resilient agricultural solutions in the context of global environmental change. This research was conducted within the Agritech National Research Center and received funding from the European Union NextGenerationEU (PIANO NAZIONALE DI RIPRESA E RESILIENZA (PNRR) – MISSIONE 4 COMPONENTE 2, INVESTIMENTO 1.4 – D.D. 1032 17/06/2022, CN00000022).