α-Glucosidase inhibitory activity of polyphenols from the burs of Castanea mollissima Blume

• Published in: Molecules (Basel, Switzerland) Vol. 19; no. 6; pp. 8373 - 8386
• Main Authors: Zhang, Jianwei, Zhao, Shan, Yin, Peipei, Yan, Linlin, Han, Jin, Shi, Lingling, Zhou, Xiaojing, Liu, Yujun, Ma, Chao
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI 19.06.2014; MDPI AG
• Subjects: alpha-Glucosidases - metabolism; Animals; Blood Glucose - drug effects; Castanea mollissima Blume; diabetic; ellagitannins; Enzyme Activation - drug effects; Fagaceae - chemistry; Hypoglycemic Agents - chemistry; Hypoglycemic Agents - therapeutic use; polyphenols; Polyphenols - chemistry; Polyphenols - therapeutic use; Rats; α-glucosidase
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules19068373

Polyphenol extracts from the burs of Castanea mollissima Blume (CMPE) exhibited potential antioxidant and hypoglycemic activities. The α-glucosidase inhibitory activities of CMPE were assessed as a means of elucidating the mechanism behind its hypoglycemic activities. In vitro studies showed that CMPE significantly inhibited both yeast α-glucosidase, through a noncompetitive mode with an IC50 of 0.33 μg/mL, and rat intestinal α-glucosidase. In vivo studies revealed that oral administration of CMPE at doses of 600 mg/kg significantly reduced postprandial blood glucose levels by 27.2% in normal rats following sucrose challenges. Gel permeation chromatography revealed that CMPE exhibited typical characteristics of high-molecular-mass polymers with mean (Mn) and weight (Mw) average molecular weights of 35.4 and 50.7 kDa, respectively, and a polydispersity (Mw/Mn) of 1.432. Acid hydrolysis analysis indicated the presence of ellagitannins. These data suggest that CMPE, enriched with ellagitannins, would be an efficacious dietary supplement for diabetes management through the inhibition of alpha-glucosidase.