Research Group of Food Functionality, Korea Food Research Institute, Bundang-gu, Sungnam-si, Gyeonggi-do, Republic of Korea.
Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
Biochem Biophys Res Commun. 2015 Jan 9;456(2):586-90. doi: 10.1016/j.bbrc.2014.11.114. Epub 2014 Dec 6.
Taste-taste interactions often showed in human psychophysical studies. Considering that each tastant in foodstuffs individually stimulates its responsible gustatory systems to elicit relevant taste modalities, taste-taste interaction should be performed in taste receptor cell-based assay. While umami substances have been proposed to suppress the bitterness of various chemicals in human sensory evaluation, the bitter-umami interaction has not been explored in bitter taste receptors, TAS2Rs. We investigated umami-bitter taste interactions by presenting umami peptides with bitter substance (salicin) on Ca(2+)-flux signaling assay using hTAS2R16-expressing cells. Five representative umami peptides (Glu-Asp, Glu-Glu, Glu-Ser, Asp-Glu-Ser, and Glu-Gly-Ser) derived from soybean markedly attenuated the salicin-induced intracellular calcium influx in a time-dependent manner, respectively, while Gly-Gly, a tasteless peptide did not. The efficacies of Glu-Glu suppressing salicin-induced activation of hTAS2R16 were higher than that of probenecid, a specific antagonist of hTAS2R16. According to Ca(2+)-flux signaling assay using the mixtures of salicin and umami peptides, all five umami peptides suppressed salicin-induced intracellular calcium influx in a noncompetitive manner. These results may provide evidence that umami peptides suppress bitter taste via bitter taste receptor(s). This is the first report which defines the interaction between bitter and umami taste in taste receptor level.
味觉相互作用在人类心理物理学研究中经常出现。考虑到食品中的每种味觉物质都会单独刺激其负责的味觉系统，从而产生相关的味觉模式，因此味觉相互作用应该在味觉受体细胞的基础上进行检测。虽然鲜味物质已被提出可以抑制人类感官评估中各种化学物质的苦味，但在苦味受体 TAS2R 中，苦味-鲜味相互作用尚未得到探索。我们通过使用表达 hTAS2R16 的细胞进行 Ca(2+) 通量信号测定，在鲜味肽与苦味物质（水杨素）存在的情况下，研究了鲜味-苦味味觉相互作用。五种代表性的鲜味肽（Glu-Asp、Glu-Glu、Glu-Ser、Asp-Glu-Ser 和 Glu-Gly-Ser）分别来自大豆，明显以时间依赖性方式减弱了水杨素诱导的细胞内钙内流，而无味肽 Gly-Gly 则没有。Glu-Glu 抑制水杨素激活 hTAS2R16 的功效高于 hTAS2R16 的特异性拮抗剂 Probenecid。根据水杨素和鲜味肽混合物的 Ca(2+) 通量信号测定，五种鲜味肽均以非竞争性方式抑制水杨素诱导的细胞内钙内流。这些结果可能为鲜味肽通过苦味受体抑制苦味提供了证据。这是首次在味觉受体水平上定义苦味和鲜味之间相互作用的报告。
