Research on degradation of polysaccharides during Hericium erinaceus fermentation

The most common type of fermentation that can change the physicochemical properties and biological activity of polysaccharide is caused by lactic acid bacteria. In this paper, the structures of Lactobacillus gasseri JM1 degraded and undegraded Hericium erinaceus polysaccharides (FHEP and HEP) were characterized, and the biological activities of the polysaccharides were determined. The result showed that polysaccharide molecular weight and monosaccharide composition changes due to fermentation degradation. FHEP had a molecular weight of 3.5 × 104 Da, which was lesser than the molecular weight of HEP (7.5 × 107 Da). HEP was composed of nine types of monosaccharides, while FHEP contained six types of monosaccharides. The results of methylation and NMR analysis results showed that after the structural link of HEP was degraded, it became FHEP, which has a branched structure. In vitro antioxidant activities and three enzyme-inhibitory activities found that FHEP had significantly higher activity than HEP (P < 0.05), indicating that the degraded polysaccharides have better biological activity.