Purification and characterization of polyphenols from chestnut astringent skin

J Agric Food Chem. 2011 Aug 24;59(16):8646-54. doi: 10.1021/jf201679q. Epub 2011 Aug 1.

Abstract

Polyphenolic compounds from chestnut astringent skin (CAS) were purified by dialysis, using Diaion HP-20 and Sephadex LH-20 columns. During purification, specific α-amylase inhibitory activities were increased about 3.4-fold, and the 50% inhibition value was 5.71 μg/mL in the Sephadex LH-20 fraction (SE-fraction). The SE-fraction contained about 67% of the total polyphenols, 57.3% of the flavanol-type tannins, and 51.3% of the procyanidins. Strong antioxidant activity was observed in the SE-fraction. Oral administration of the SE-fraction in rats fed corn starch significantly suppressed an increase in blood glucose levels. The SE-fraction contained gallic acid and ellagic acid. The MALDI-TOF spectrum showed a peak series exhibiting a mass increment of 288 Da, reflecting the variation in the number of catechin/epicatechin units. Our results suggest CAS contains polyphenols with strong α-amylase inhibitory activity. The data also suggest CAS polyphenols might be oligomeric proanthocyanidins with gallic acid and ellagic acid.

MeSH terms

  • Aesculus / chemistry*
  • Animals
  • Blood Glucose / analysis
  • Enzyme Inhibitors / pharmacology
  • Humans
  • Plant Extracts / administration & dosage
  • Plant Extracts / chemistry
  • Polyphenols / chemistry
  • Polyphenols / isolation & purification*
  • Polyphenols / pharmacology
  • Proanthocyanidins / isolation & purification
  • Proanthocyanidins / pharmacology
  • Rats
  • Seeds / chemistry*
  • Swine
  • Tannins / isolation & purification
  • alpha-Amylases / antagonists & inhibitors

Substances

  • Blood Glucose
  • Enzyme Inhibitors
  • Plant Extracts
  • Polyphenols
  • Proanthocyanidins
  • Tannins
  • alpha-Amylases