Inhibitory effects of edible seaweeds, polyphenolics and alginates on the activities of porcine pancreatic α-amylase

Food Chem. 2018 Apr 15:245:1196-1203. doi: 10.1016/j.foodchem.2017.11.027. Epub 2017 Nov 9.

Abstract

Edible seaweeds are valuable because of their organoleptic properties and complex polysaccharide content. A study was conducted to investigate the potential of dried edible seaweed extracts, its potential phenolic compounds and alginates for α-amylase inhibitory effects. The kinetics of inhibition was assessed in comparison with acarbose. The methanol extract of Laminaria digitata and the acetone extract of Undaria pinnatifida showed inhibitory activity against α-amylase, IC50 0.74 ± 0.02 mg/ml and 0.81 ± 0.03 mg/ml, respectively; both showed mixed-type inhibition. Phenolic compound, 2,5-dihydroxybenzoic acid was found to be a potent inhibitor of α-amylase with an IC50 value of 0.046 ± 0.004 mg/ml. Alginates found in brown seaweeds appeared to be potent inhibitors of α-amylase activity with an IC50 of (0.075 ± 0.010-0.103 ± 0.017) mg/ml, also a mixed-type inhibition. Overall, the findings provide information that crude extracts of brown edible seaweeds, phenolic compounds and alginates are potent α-amylase inhibitors, thereby potentially retarding glucose liberation from starches and alleviation of postprandial hyperglycaemia.

Keywords: Alginate; Glucose liberation; Hyperglycaemia; Inhibitor; Phenolic compound; Seaweed; α-Amylase.

MeSH terms

  • Acarbose / pharmacology
  • Alginates / pharmacology*
  • Animals
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology*
  • Gentisates / pharmacology
  • Hyperglycemia / drug therapy
  • Inhibitory Concentration 50
  • Laminaria / chemistry
  • Pancreatic alpha-Amylases / antagonists & inhibitors*
  • Pancreatic alpha-Amylases / metabolism
  • Polyphenols / pharmacology*
  • Seaweed / chemistry*
  • Swine
  • Undaria / chemistry

Substances

  • Alginates
  • Enzyme Inhibitors
  • Gentisates
  • Polyphenols
  • Pancreatic alpha-Amylases
  • Acarbose
  • 2,5-dihydroxybenzoic acid