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Different phenolic compounds activate distinct human bitter taste receptors

Susana Soares1, Susann Kohl, Sophie Thalmann

  • 1Department of Chemistry, University of Porto, Porto, Portugal.

Journal of Agricultural and Food Chemistry
|January 15, 2013
PubMed

Insights

Polyphenols in foods like wine and chocolate activate bitter taste receptors (TAS2Rs). Specific compounds like PGG and malvidin-3-glucoside are potent activators, explaining food bitterness.

Area of Science:

  • * Sensory Science and Molecular Biology
  • * Food Chemistry and Nutrigenomics

Background:

  • * Polyphenols are prevalent in plant-derived foods and beverages, contributing to bitterness.
  • * These compounds possess significant health benefits, acting as chemopreventive agents.
  • * The activation of human bitter taste receptors (TAS2Rs) by polyphenols is not fully understood.

Purpose of the Study:

  • * To investigate the activation profiles of human TAS2Rs by six common polyphenol compounds.
  • * To identify specific polyphenols responsible for bitterness in foods like red wine, beer, tea, and chocolate.
  • * To elucidate the structural determinants of polyphenol interaction with TAS2Rs.

Main Methods:

  • * Analysis of bitter taste receptor (TAS2R) activation by six selected polyphenols: pentagalloylglucose (PGG), (-)-epicatechin, procyanidin dimer B3, procyanidin trimer C2, malvidin-3-glucoside, and cyanidin-3-glucoside.
  • * Quantification of receptor activation using EC50 values.
  • * Structure-activity relationship analysis focusing on catechol and galloyl groups.

Main Results:

  • * Different polyphenols activated distinct combinations of TAS2Rs.
  • * (-)-Epicatechin activated TAS2R4, TAS2R5, and TAS2R39; PGG activated TAS2R5 and TAS2R39.
  • * Malvidin-3-glucoside and procyanidin trimer showed high potency for TAS2R7 and TAS2R5, respectively. Tannins were identified as potent agonists for TAS2R5.

Conclusions:

  • * Polyphenols exhibit diverse activation patterns across human TAS2Rs.
  • * Tannins are potent activators of TAS2R5, with catechol/galloyl groups being key structural features.
  • * PGG and malvidin-3-glucoside are significant contributors to food bitterness, even at low concentrations.

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