Aggregation behavior and structure analysis of rice bran protein aggregates regulated by ferulic acid

This study investigated how ferulic acid (FA) affects the aggregation, morphology, and structure of oxidized rice bran protein (RBP).Results showed that FA reduced ThT fluorescence intensity and β-sheet content, caused λ_max red shifts, indicating inhibition of protein oxidative aggregation. The aggregation process through three stages based on induction time: initial (0-5 h), growth (10h), and mature (30-50 h). During initial stage, smaller soluble spherical aggregates were observed, and these can be inhibited by FA. During growth stage, aggregates developed into spherical cluster aggregates, which be suppressed by FA. During mature stage, a mixture of amorphous, cross-linked, and fibrous aggregates were observed, FA partially inhibited these aggregates. FA also altered disulfide bond transitions from intermolecular to intramolecular and modified amino acid side chains polarity. These findings indicate that FA inhibits oxidized RBP aggregates by reorganizing secondary/tertiary structures and regulating disulfide bonds, offering theory for RBP storage and FA-mediated regulation.