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Taste Exam: A Brief and Validated Test
Published on: August 17, 2018
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
Summary
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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