amarogentin
compound / compound-amarogentin
アマロゲンチン
Amarogentin is a secoiridoid glycoside found in gentian root. In the literature, it is repeatedly described as "the most bitter substance known"; records of its bitter value are listed below.
On this page (8 sections)
Reading the bitterness
Amarogentin is a secoiridoid glycoside found in gentian root; its content in the dried root is reported to be approximately 0.025–0.4% (2–8% of the total bitter constituents). It is a compound described repeatedly in the literature as 「知られている中で最も苦い物質」(in translation: "the most bitter substance known").
This evaluation as 「最も苦い」(in translation: "the most bitter") is a textbook description based on traditional sensory measurement by the Ph.Eur.-type dilution method, known as bitterness value, in which amarogentin shows a vastly different value of 58,000,000 compared to gentiopicroside's bitterness value of 12,000. Recent determination of detection thresholds has not yet reached the primary reporting stage, and one cannot equate the textbook values directly with the latest measured values.
At the receptor level, in assays using a heterologous expression system, amarogentin was identified as an agonist of the human bitter receptor hTAS2R50, which had previously been an orphan receptor, together with the natural bitter terpenoid andrographolide. However, this finding is confirmed only at the abstract level, and quantitative indicators such as EC50 or the concentration required for activation cannot be claimed at this stage.
In an analysis of a Gentianaceae bitter herb Swertia chirayita that was related to gentian, an ethanol extract was fractionated into numerous fractions by preparative HPLC, and sensory evaluation by a panel of tasters was correlated with chemical profiling. In fractions 34–39, the bitterness showed a correlation coefficient exceeding 0.95 with the presence of amarogentin. In the crude extract as a whole, bitterness accounted for over 85% of the detected taste attributes. In the same analysis, amaroswerin and a decentapicrin derivative were also identified as compounds correlating with bitterness.
Sources for this overview
Assessment report on Gentiana lutea L., radix (EMA/HMPC/607863/2017)
Checked for this overview: Confirmed the notation of dried root content and bitterness value. / The content in the dried root and the proportion relative to total bitter constituents come from this source. / The numerical values for bitterness value (comparison between gentiopicroside and amarogentin) come from this source.
An improved method for the isolation of amarogentin, the bitter principle of yellow gentian roots
Checked for this overview: Confirmed the positioning as a textbook-level evaluation.
Checked for this overview: Confirmed the identification of TAS2R50 activation.
Checked for this overview: Correlation coefficient exceeding 0.95 between the bitterness of the fractions and amarogentin.
Follow the connections
amarogentin →activates→ TAS2R50
Measured values (1)
| Kind | Compound | Target | Value | Conditions | Source |
|---|---|---|---|---|---|
| concentration | amarogentin | gentian root | 0.025-0.4 % | Dried gentian root (summary of literature from the EMA assessment report). (Total bitter constituents: 2–8%.) | Committee on Herbal Medicinal Products (HMPC), 2018 |
Values are the reported values of each source (with units and conditions). Thresholds and EC50 depend on the panel and method; they are not single true values.
Structured claims — open a section to read each claim's confidence, evidence and limits
Sensory (2)
Scope: A value reported in European pharmacognosy textbook literature (bitterness value by the dilution method).
Show data
compound-amarogentin —has_reported_bitter_value_of→ "Bitterness value 58,000,000. Described as "the most bitter substance known.""Scope: Layer: food (plant extract and fractionated samples). Fractionation by preparative HPLC, sensory intensity evaluation by panelists (up to 7 fractions per session, 1 fraction evaluated at a time), correlation analysis with NMR and LC-HRMS/MS (partial least squares discriminant analysis).
Show data
compound-amarogentin —is_a_bitter_principle_of→ "In an analysis of Swertia chirayita, a Gentianaceae bitter herb related to gentian, an ethanol extract was fractionated into numerous fractions by preparative HPLC, and sensory evaluation by a panel of tasters was correlated with chemical profiling. In fractions 34–39, the bitterness showed a strong correlation (correlation coefficient exceeding 0.95) with the presence of amarogentin. In the crude extract as a whole, bitterness accounted for over 85% of the detected taste attributes. In the same analysis, amaroswerin and a decentapicrin derivative were also identified as compounds correlating with bitterness."Mechanism and receptors (1)
Scope: A receptor assay in a heterologous expression system (cultured cells)
Note: GtoPdb also lists amarogentin as an agonist of TAS2R46 (affinity 4.2, PMID 26406243). The TAS2R46 side is kept here in these notes rather than made a separate claim (because the primary paper has not been read).
Show data
compound-amarogentin —activates→ receptor-tas2r50