Triterpenes gymnema sylvestre

Gymnemoside b (triterpene glycoside) Gymnema sylvestre (Asclepiadaceae) [leaf] 4- Glc absorption... 

Human taste response is modified by several plant-derived substances. The detergent sodium dodecyl sulfate, as well as triterpene saponins from the leaves of several plant species (most notably Gymnema sylvestre and Ziziphus jujuba) will temporarily inhibit the sweet taste sensation in man the duration of the effect being about one hour for G. sylvestre and about fifteen minutes for Z. jujuba. The mechanism of action seems to be related, in part, to the surfactant properties of the materials. Structures of the modifiers and possible mechanisms of action are discussed. 

A substance isolated from the Indian shrub Gymnema sylvestre, has a profound ability to reduce perceived sweetness of sugar solutions. The effect was noticed over a century ago when two British inhabitants of an Indian village found that, after chewing the leaves of G sylvestre, the sweetness of their tea disappeared (7). The sweetness suppressing activity is due to a mixture of several triterpene saponins which have collectively been termed the gymnemic acids. For most people exposed to the effects of GA, sweetness suppression is complete and the effect lasts for about an hour. 

Gynmemic acid(s) Inhibit(s) sweet taste for several hours (powder sugar tastes like sand and sugar solution tastes like plain tapwa-ter). Salty, bitter, and sour tastes are not affected. Various triterpene glycosides isolated from the leaves of Gymnema sylvestre. 

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