Modulation of bitter taste receptors by yeast extracts

[Display omitted] •AMP and AMP-rich YE (yeast extract) activated more TAS2Rs than IMP-rich YE.•AMP-rich YE inhibited TAS2R7, 9, 10, 14, 16, 38 and 43.•Seven TAS2Rs showed at least 40% inhibition after treatment with AMP-rich YE.•Similar IC50 values were measured for these seven inhibited TAS2Rs.•Competitive and noncompetitive inhibitions of AMP-rich YE were highlighted. Yeast extracts (YEs) are used in foods because of their flavour properties and ability to reduce bitterness. The adenosine 5′-monophosphate (AMP) found in YEs is known to decrease the bitterness of some compounds. This study aimed to investigate the ability of YEs to inhibit bitter taste receptors (TAS2Rs) using in vitro cell-based assays. A screen of TAS2Rs activated by AMP and YEs revealed that AMP and the AMP-rich YE activated more TAS2Rs. The inhibitory effect of the AMP-rich YE on seven TAS2Rs activated by bitter agonists was studied. YE reduced TAS2R activation, increased the EC50 value and decreased the maximum amplitude, demonstrating competitive and non-competitive inhibitions. Amongst the nineteen TAS2Rs tested, seven showed 40 % or greater inhibition after treatment of AMP-rich YE. Our data provide a better understanding of the TAS2R inhibition mechanism of AMP-rich YEs and promote their use as a strategy to reduce bitterness in foods and medicines.