Impact of exopolysaccharide derivatization on the physicochemical properties and stability of core-shell microgels

The aim of this study was to investigate the effect of different chemically modified yeast exopolysaccharides (EPS) derivatives on the stability of EPS derivative-chitosan-based shell and core microgels. Three EPS derivatives with different physicochemical properties were prepared by carboxymethylation (C-EPS), sulfation (S-EPS), and phosphorylation (P-EPS) modifications, respectively. Chitosan was used as the inner shell and the EPS derivatives as the outer shell, and bovine serum albumin (BSA) and mucin were loaded into the core-shell microgels by ionic gelation. Dynamic light scattering, SEM, and FTIR were used to explore the physical and chemical properties. Significantly, P-EPS based microgel exhibited an exceptional mucin binding capacity of 92.37 %. Besides, the derivatives of EPS contribute to enhancing the low-temperature stability of core-shell microgels and developing novel antioxidants. The results elucidated the constitutive relationship between the structures of different EPS derivatives and their ability to stabilize microgels, and providing theoretical basis and technical support for the development of new, efficient and multifunctional natural food delivery systems.