Intermolecular interaction between fucoidan and casein: A combined spectroscopic and docking study

Fucoidan, a sulphated polysaccharide derived from brown seaweed, has attracted considerable interest due to its bioactivity and potential as a functional food ingredient. Understanding its interactions with food proteins such as casein is important for designing stable and functional biopolymer systems. Therefore, this study aimed to investigate the intermolecular interactions between fucoidan and casein using spectroscopic analysis and molecular docking simulations. Spectral changes in ATR-FTIR and binding patterns from molecular docking consistently indicate that fucoidan interacts with casein primarily through hydrogen bonding and electrostatic forces. Turbidity measurements further supported fucoidan–casein complex formation. Together, these results contribute to a better understanding of the molecular interactions between fucoidan and casein.