The nutraceutical role of the Phaseolus vulgaris alpha-amylase inhibitor

Br J Nutr. 2008 Jul;100(1):1-12. doi: 10.1017/S0007114508879135. Epub 2008 Mar 11.


The present review assesses the potential of the Phaseolus vulgaris alpha-amylase inhibitor isoform 1 (alpha-AI1) starch blockers as a widely used remedy against obesity and diabetes. Consumption of the alpha-amylase inhibitor causes marginal intraluminal alpha-amylase activity facilitated by the inhibitor's appropriate structural, physico-chemical and functional properties. As a result there is decreased postprandial plasma hyperglycaemia and insulin levels, increased resistance of starch to digestion and increased activity of colorectal bacteria. The efficacy and safety of the amylase inhibitor extracts, however, depend on the processing and extraction techniques used. The extracts are potential ingredients in foods for increased carbohydrate tolerance in diabetics, decreased energy intake for reducing obesity and for increased resistant starch. Research developments in the distribution and biosynthesis of the alpha-amylase inhibitor, relevant physico-chemical properties, the molecular starch-blocking mechanism, anti-obesity and anti-diabetes effects, safety of extracts and the need for research into their potential anti-colorectal cancer effect are discussed.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Anti-Obesity Agents / therapeutic use
  • Chemistry, Physical
  • Diabetes Mellitus / drug therapy
  • Dietary Supplements*
  • Humans
  • Hypoglycemic Agents / therapeutic use
  • Obesity / drug therapy
  • Plant Lectins / adverse effects
  • Plant Lectins / chemistry
  • Plant Lectins / therapeutic use*


  • Anti-Obesity Agents
  • Hypoglycemic Agents
  • Plant Lectins
  • alpha-amylase inhibitor, Phaseolus vulgaris