Gymnemic acids are a class of chemical compounds isolated from the leaves of Gymnema sylvestre (Asclepiadaceae). They are anti-sweet compounds, or sweetness inhibitors. After chewing the leaves, solutions sweetened with sugar taste like water.
Chemically, gymnemic acids are triterpenoid glycosides. The central structure is the aglycone gymnemagenin (C30H50O6). This is adorned with a sugar such as glucuronic acid and with various ester groups. These variations give rise to the different gymnemic acids. More than 20 homologs of gymnemic acid are known.
Gymnemic acid I has the highest anti-sweet properties. It suppresses the sweetness of most of the sweeteners including intense artificial sweeteners such as aspartame and natural sweeteners such as thaumatin, a sweet protein. The anti-sweet activity is reversible, but sweetness recovery on the tongue can take more than 10 minutes.
Example chemical structures
|Name||Gymnemic acid I||Gymnemic acid II||Gymnemic acid III||Gymnemic acid IV|
|Molar mass (g/mol)||806.98||809.00||766.97||764.95|
- Hodulcine, a dammarane-type triterpene glycoside from the leaves of Hovenia dulcis
- Lactisole, sodium 2-(4-methoxyphenoxy)propanoate
- Ziziphin, a triterpene glycoside, C51H80O18
- Stoecklin, Walter (1969). "Chemistry and physiological properties of gymnemic acid, the antisaccharine principle of the leaves of Gymnema sylvestre". Journal of Agricultural and Food Chemistry. 17 (4): 704. doi:10.1021/jf60164a011.
- CID 10051937 from PubChem
- Sheng, Huaming; Sun, Hongbin (2011). "Synthesis, biology and clinical significance of pentacyclic triterpenes: A multi-target approach to prevention and treatment of metabolic and vascular diseases". Natural Product Reports. 28 (3): 543. doi:10.1039/C0NP00059K. PMID 21290067.
- AD kinghorn and CM Compadre (1991). L O'Brien Nabors, ed. Less common high-potency sweeteners. Alternative Sweeteners (2nd ed.). New York: Marcel Dekker. ISBN 0-8247-8475-8.
- Kurihara, Yoshie (1992). "Characteristics of antisweet substances, sweet proteins, and sweetness‐inducing proteins". Critical Reviews in Food Science and Nutrition. 32 (3): 231–52. doi:10.1080/10408399209527598. PMID 1418601.