Possible role of polysaccharide in modulating digestion of potato starch digesta.

The effect of deproteinized Tremella olysaccharide (DTP) on the digestion of potato starch (PS) was investigated. DTP reduced the hydrolysis rate of PS in a concentration-dependent manner, with digestion rates of 76.99 %, 72.03 %, and 29.73 % after 180 min for 0.3, 0.6, and 1.2 mg/mL DTP, respectively. DTP delayed digestion by shifting the kinetics from single-phase to biphasic behavior. It significantly inhibited pancreatic α-amylase (IC = 5.76 mg/mL) by modifying the enzyme's secondary structure and reducing substrate binding. Additionally, DTP enhanced digesta viscosity, which may have contributed to the reduction in postprandial glucose release, thereby supporting its role as a potential hypoglycemic agent. However, DTP exhibited minimal glucose adsorption, binding only 1.2 % of 100 mM glucose at 1.2 mg/mL. These findings suggest that DTP reduces starch digestion primarily by inhibiting α-amylase activity and increasing digestive viscosity, providing insights into its hypoglycemic potential.