Novel peptides with α-glucosidase inhibitory activity from Changii Radix hydrolysates

The objective of this research was to investigate the alpha-glucosidase inhibitory activity of peptides released from Changii Radix protein under the optimal enzymatic hydrolysis conditions of trypsin, flavourzyme, compound proteinase, papain, alkaline proteinase, neutral protease, and in vitro simulated human gastrointestinal digestive conditions. The hydrolysate with the best activity was further purified by ultrafiltration, size-exclusion chromatography and semi-preparative high performance liquid chromatography. The peptides in the most active fraction were subsequently identified by nano-LC-MS/MS and screened for bioactivity. As a result, the GID-3-SG2-RP-2 fraction (with smaller molecular weight and more hydrophobic) manifested the highest effect with an IC50 value of 32 gg/mL. Three peptides of this fraction were synthesized, SQHISTAGMEASGTSNMKF, KVIISAPSKDAPMF, and STFQQMW, and provided an IC50 of 1.051, 0.032, and 1.104 mg/mL, respectively. Thus, the results indicated that Changii Radix derived peptides may have potential functions in the prevention and management of type 2 diabetes.

Automated summary

The research aimed to investigate the alpha-glucosidase inhibitory activity of peptides derived from Changii Radix protein under various enzymatic and digestive conditions. The most active fraction, GID-3-SG2-RP-2, exhibited the highest effect, suggesting the potential role of Changii Radix peptides in the prevention and management of type 2 diabetes.