Characterization of Bitter Compounds via Modulation of Proton Secretion in Human Gastric Parietal Cells in Culture

• Published in: Journal of agricultural and food chemistry 2018-03, Vol.66 (10), p.2295-2300
• Main Authors: Liszt, Kathrin I, Hans, Joachim, Ley, Jakob P, Köck, Elke, Somoza, Veronika
• Format: Article
• Language: English
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/acs.jafc.7b01051

Humans perceive bitterness via around 25 different bitter receptors. Therefore, the identification of antagonists remains a complex challenge. We previously demonstrated several bitter-tasting compounds such as caffeine to induce acid secretion in the stomach and in a human gastric tumor cell line (HGT-1). Here, the results of a fluorescent-based in vitro assay using HGT-1 cells and a human sensory panel testing nine selected potential bitter modulators, with or without the bitter compounds caffeine or theobromine, were compared. Of the bitter-modulating compounds tested, eriodictyol, matairesinol, enterolacton, lariciresinol, and homoeriodictyol reduced the effect of caffeine on proton secretion by −163 ± 14.0, −152 ± 12.4, −74 ± 16.4, −58 ± 7.2, and −44.6 ± 16.5%, respectively, and reduced the bitter intensity of caffeine in the human sensory panel. In contrast, naringenin and 5,7-dihydroxy-4­(4-hydroxyphenyl)­chroman-2-one neither reduced the caffeine-induced proton secretion in HGT-1 cells nor showed an effect on bitter intensity perceived by the sensory panel. Results for theobromine were not as pronounced as those for caffeine, but followed a similar trend. The results demonstrate that the HGT-1 in vitro assay is a useful tool to identify potential bitter-masking compounds. Nevertheless, a sensory human panel is necessary to quantify the bitter-masking potency.