Roland Wibke S U, Gouka Robin J, Gruppen Harry, Driesse Marianne, van Buren Leo, Smit Gerrit, Vincken Jean-Paul
Laboratory of Food Chemistry, Wageningen University, Wageningen, The Netherlands.
Unilever R&D, Vlaardingen, The Netherlands.
PLoS One. 2014 Apr 10;9(4):e94451. doi: 10.1371/journal.pone.0094451. eCollection 2014.
Many (dietary) bitter compounds, e.g. flavonoids, activate bitter receptor hTAS2R39 in cell-based assays. Several flavonoids, amongst which some flavanones, are known not to activate this receptor. As certain flavanones are known to mask bitter taste sensorially, flavanones might act as bitter receptor antagonists. Fourteen flavanones were investigated for their potential to reduce activation of hTAS2R39 by epicatechin gallate (ECG), one of the main bitter compounds occurring in green tea. Three flavanones showed inhibitory behavior towards the activation of hTAS2R39 by ECG: 4'-fluoro-6-methoxyflavanone, 6,3'-dimethoxyflavanone, and 6-methoxyflavanone (in order of decreasing potency). The 6-methoxyflavanones also inhibited activation of hTAS2R14 (another bitter receptor activated by ECG), though to a lesser extent. Dose-response curves of ECG at various concentrations of the full antagonist 4'-fluoro-6-methoxyflavanone and wash-out experiments indicated reversible insurmountable antagonism. The same effect was observed for the structurally different agonist denatonium benzoate.
许多（膳食中的）苦味化合物，如黄酮类化合物，在基于细胞的检测中可激活苦味受体hTAS2R39。已知几种黄酮类化合物，其中一些黄烷酮，不会激活该受体。由于某些黄烷酮已知在感官上可掩盖苦味，因此黄烷酮可能充当苦味受体拮抗剂。研究了14种黄烷酮对表没食子儿茶素没食子酸酯（ECG，绿茶中主要的苦味化合物之一）激活hTAS2R39的潜在抑制作用。三种黄烷酮对ECG激活hTAS2R39表现出抑制作用：4'-氟-6-甲氧基黄烷酮、6,3'-二甲氧基黄烷酮和6-甲氧基黄烷酮（按效力递减顺序排列）。6-甲氧基黄烷酮也抑制hTAS2R14（另一种被ECG激活的苦味受体）的激活，不过程度较小。在不同浓度的完全拮抗剂4'-氟-6-甲氧基黄烷酮作用下ECG的剂量反应曲线和洗脱实验表明存在可逆的不可逾越的拮抗作用。对于结构不同的激动剂苯甲地那铵也观察到了相同的效果。
