Studies on the binding characteristics of three polysaccharides with different molecular weight and flavonoids from corn silk (Maydis stigma)

Polysaccharides and flavonoids co-existed in corn silk (Maydis stigma) could interact inevitably during processing and digestion. In this study, the binding interaction between three polysaccharides with different molecular weight and flavonoids from corn silk was characterized using molecular dynamic and thermodynamic simulation. And the corn silk polysaccharides-flavonoids complex (CSP - CSF complex) was characterized using fourier transform infrared (FT-IR) spectra, circular dichroism (CD), scanning electron microscope (SEM) and differential scanning calorimetry (DSC). The three polysaccharides from corn silk showed the molecular weight distributions of 43.3 kDa, 61.3 kDa and 106.6 kDa, respectively, and they had the same monosaccharide types with different ratios. The adsorption of flavonoids to polysaccharides might be mostly driven by van der Waals forces and hydrogen bonding, and it could be described through various isothermal models and thermodynamic equations such as Langmuir, Freundlich equations and Clausius-Clapeyron equation. This type of interactions could improve the biological activities of polysaccharides such as alpha-amylase and alpha-glucosidase inhibition.