Sequential extraction, preliminary characterization and functional properties of sesame (Sesamum indicum L.) hull polysaccharides

To expand the applications of sesame hull waste produced from industrial processing, five cell wall polysaccharide fractions of sesame hulls were sequentially extracted with water (WSP), chelator (CSP), sodium carbonate (NSP), 1 mol/L potassium hydroxide (KS1), and 4 mol/L potassium hydroxide (KS4). The preliminary structural characteristics of the five polysaccharide fractions were investigated by analytical techniques, such as sugar composition analysis, UV-vis, FT-IR, molecular weight measurement, and HSQC. The results showed that CSP had the main chain of xylogalacturonans and the content of galacturonic acid reached 70.07 g/100 g. Both KS1 and KS4 had xyloglucans backbones. NSP had the lowest molecular weight and the best thermal stability, while KS4 had the highest molecular weight. Rheological measurement indicated KS4 had the highest viscosity. The antioxidant abilities of NSP and KS1 were stronger than the other three fractions. This study provides valuable new information about the structural and functional properties of cell wall polysaccharides from sesame hulls.

Automated summary

This study investigated the extraction, structural characteristics, and functional properties of five cell wall polysaccharide fractions from sesame hulls. The polysaccharide fractions showed different structures and functional properties, such as different main chains and molecular weights, as well as varying antioxidant abilities and viscosity.