Absorption and transport of polysaccharides from soybean seed coat in the Caco-2 cell model and their interaction with the MUC2 protein

Polysaccharides derived from soybean seed coats exhibit diverse functional properties and significant application potential; however, their intestinal absorption and transport mechanisms remain poorly understood. This study investigates the molecular docking interactions of two soybean seed coat polysaccharides (NMSP and CSSP), extracted using different methods, with the MUC2 protein, and explores their absorption and transport properties using Caco-2 cell models. Molecular dynamics simulations revealed the binding modes and key interaction sites between NMSP, CSSP, and the MUC2 protein. A Caco-2 monolayer model was established to evaluate polysaccharide uptake and transport under varying concentrations, temperatures, and pH conditions. The results demonstrated that the absorption of both polysaccharides was time- and concentration-dependent, while transport analyses revealed that both NMSP and CSSP could traverse the Caco-2 cells, primarily via endocytic pathways. In terms of apparent permeability (Papp) and transport rate, CSSP exhibited moderate absorption, whereas NMSP was classified as poorly absorbed. Moreover, acidic conditions significantly enhanced the transport rates of both polysaccharides. This study provides critical insights into the absorption and transport characteristics of soybean seed coat polysaccharides, offering a theoretical foundation for further exploration of their bioavailability and physiological functions.