From molecular assembly to biological function: an ovalbumin-fucoidan complex stabilized emulsion for enhancing the antioxidant efficacy of galangin.

The effective delivery of hydrophobic bioactive compounds remains a major challenge in functional food and nutraceutical applications because of their poor aqueous solubility, limited physicochemical stability, and insufficient bioavailability. In this study, ovalbumin-fucoidan (OVA-FUC) complexes were constructed as food-grade stabilizers to develop galangin (GAL)-loaded emulsions with improved stability and antioxidant efficacy. The interaction mechanism, emulsion stability, and antioxidant activity were evaluated using structural characterization, interfacial analysis, storage tests, chemical antioxidant assays, and an ethanol-induced oxidative stress model in Caenorhabditis elegans. Results showed that OVA and FUC formed complexes mainly through hydrogen bonding and hydrophobic interactions. The 1-1 OVA-FUC complex exhibited the most favorable interfacial behavior and produced emulsions with superior storage stability. The GAL-loaded emulsion showed strong ABTS radical-scavenging activity (74.33 ± 7.60%) and effectively reduced ROS, lipofuscin, and MDA levels while increasing glutathione content and improving locomotor activity in C. elegans. These findings reveal that controlled OVA-FUC interactions can optimize interfacial assembly and emulsion stability, offering a practical strategy to improve the functional delivery of hydrophobic antioxidants in food systems.