Gymnema sylvestre | |
---|---|
Gymnema sylvestre, at Eastern Ghats, India | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Gentianales |
Family: | Apocynaceae |
Genus: | Gymnema |
Species: | G. sylvestre |
Binomial name | |
Gymnema sylvestre | |
Gymnema sylvestre [1] is a perennial woody vine native to Asia (including the Arabian Peninsula), Africa and Australia. It has been used in Ayurvedic medicine. Common names include gymnema, [2] Australian cowplant, and Periploca of the woods, and the Hindi term gurmar, which means "sugar destroyer". [3] [4] [5]
The leaves and extracts contain gymnemic acids, the major bioactive constituents that interact with taste receptors on the tongue to temporarily suppress the taste of sweetness. [6] [7] [8] [9] [10]
The plant is a climber with leaves having soft hairs on the upper surface. The leaves are elongated-oval in shape. It has a small, yellow, umbelliferous inflorescence that is produced throughout the year. [11]
Gymnema sylvestre has a long history of use in herbal medicine and a broad range of therapeutic properties. [4] [5] [12]
Its leaves contain triterpenoid saponins, [13] [14] [15] flavonols, [16] and gurmarin. [5] The major biologically active plant molecules are gymnemic acids, a class of triterpenoid saponins, which have the effect of suppressing the taste of sweetness on the tongue from sucrose (sugar), stevia, xylitol, and artificial sweeteners such as aspartame. [17]
The sweet-blocking effect of G. sylvestre lasts from 15 [6] to 50 minutes [18] and may even persist for several hours. [19] Gymnemic acids apparently have no long-term effects on taste and they do not influence bitter, salty, or sour taste perception. [7] [20]
Gymnemic acid compounds in Gymnema sylvestre can also attach to receptors on the intestinal walls, helping to reduce absorption of sugar molecules in the gut. [21] This process can lower blood sugar and promote insulin secretion and release. [21] However, its antidiabetic properties were not confirmed in rats. [22]
Gymnema derives from the Greek words gymnos (γυμνὀς) and nēma (νῆμα) meaning "naked" and "thread", respectively; the species epitheton sylvestre means "of the forest" in Latin. [29]
The Hindi and Urdu name gurmar, Sanskrit मधुनाशिनी (madhunashini), Malayalam chakkarakolli, Tamil சிறுகுறுஞ்சான், and Telugu పొడపత్రి (podapatri), all literally mean "sugar destroyer". (Sanskrit) meshashringi translates as "ram's horn", a name given to the plant due to the shape of its fruits.
Stevia is a sweet sugar substitute that is about 50 to 300 times sweeter than sugar. It is extracted from the leaves of Stevia rebaudiana, a plant native to areas of Paraguay and Brazil. The active compounds in stevia are steviol glycosides. Stevia is heat-stable, pH-stable, and not fermentable. Humans cannot metabolize the glycosides in stevia, and it therefore has zero calories. Its taste has a slower onset and longer duration than that of sugar, and at high concentrations some of its extracts may have an aftertaste described as licorice-like or bitter. Stevia is used in sugar and calorie-reduced food and beverage products as an alternative for variants with sugar.
Umami, or savoriness, is one of the five basic tastes. It is characteristic of broths and cooked meats.
Liquorice or licorice is the common name of Glycyrrhiza glabra, a flowering plant of the bean family Fabaceae, from the root of which a sweet, aromatic flavouring is extracted.
Herbal medicine is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. With worldwide research into pharmacology, some herbal medicines have been translated into modern remedies, such as the anti-malarial group of drugs called artemisinin isolated from Artemisia annua, a herb that was known in Chinese medicine to treat fever. There is limited scientific evidence for the safety and efficacy of many plants used in 21st-century herbalism, which generally does not provide standards for purity or dosage. The scope of herbal medicine sometimes includes fungal and bee products, as well as minerals, shells and certain animal parts.
In chemistry, a glycoside is a molecule in which a sugar is bound to another functional group via a glycosidic bond. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. These can be activated by enzyme hydrolysis, which causes the sugar part to be broken off, making the chemical available for use. Many such plant glycosides are used as medications. Several species of Heliconius butterfly are capable of incorporating these plant compounds as a form of chemical defense against predators. In animals and humans, poisons are often bound to sugar molecules as part of their elimination from the body.
Medicinal plants, also called medicinal herbs, have been discovered and used in traditional medicine practices since prehistoric times. Plants synthesize hundreds of chemical compounds for various functions, including defense and protection against insects, fungi, diseases, and herbivorous mammals.
Stevia rebaudiana is a plant species in the genus Stevia of the family Asteraceae. It is commonly known as candyleaf, sweetleaf or sugarleaf.
Miraculin is a taste modifier, a glycoprotein extracted from the fruit of Synsepalum dulcificum. The berry, also known as the miracle fruit, was documented by explorer Chevalier des Marchais, who searched for many different fruits during a 1725 excursion to its native West Africa.
Sweetness is a basic taste most commonly perceived when eating foods rich in sugars. Sweet tastes are generally regarded as pleasurable. In addition to sugars like sucrose, many other chemical compounds are sweet, including aldehydes, ketones, and sugar alcohols. Some are sweet at very low concentrations, allowing their use as non-caloric sugar substitutes. Such non-sugar sweeteners include saccharin, aspartame, sucralose and stevia. Other compounds, such as miraculin, may alter perception of sweetness itself.
Synsepalum dulcificum is a plant in the Sapotaceae family, native to tropical Africa. It is known for its berry that, when eaten, causes sour foods subsequently consumed to taste sweet. This effect is due to miraculin. Common names for this species and its berry include miracle fruit, miracle berry, miraculous berry, sweet berry, and in West Africa, where the species originates, àgbáyun, taami, asaa, and ledidi.
An astringent is a chemical that shrinks or constricts body tissues. The word derives from the Latin adstringere, which means "to bind fast". Astringency, the dry, puckering or numbing mouthfeel caused by the tannins in unripe fruits, lets the fruit mature by deterring eating. Tannins, being a kind of polyphenol, bind salivary proteins and make them precipitate and aggregate, producing a rough, "sandpapery", or dry sensation in the mouth.
Theanine, commonly known as L-theanine and sometimes L-gamma-glutamylethylamide or N5-ethyl-L-glutamine, is an amino acid analogue of the proteinogenic amino acids L-glutamate and L-glutamine and is found primarily in particular plant and fungal species. It was discovered as a constituent of green tea in 1949 and isolated from gyokuro leaves in 1950, thus rendering it a natural product. It constitutes about 1–2% of the dry weight of green tea leaves.
Arctium lappa, commonly called greater burdock, gobō (牛蒡/ゴボウ), edible burdock, lappa, beggar's buttons, thorny burr, or happy major is a Eurasian species of plants in the family Asteraceae, cultivated in gardens for its root used as a vegetable. It has become an invasive weed of high-nitrogen soils in North America, Australia, and other regions.
Kaempferol (3,4′,5,7-tetrahydroxyflavone) is a natural flavonol, a type of flavonoid, found in a variety of plants and plant-derived foods including kale, beans, tea, spinach, and broccoli. Kaempferol is a yellow crystalline solid with a melting point of 276–278 °C (529–532 °F). It is slightly soluble in water and highly soluble in hot ethanol, ethers, and DMSO. Kaempferol is named for 17th-century German naturalist Engelbert Kaempfer.
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.
Ziziphin, a triterpene glycoside which exhibits taste-modifying properties, has been isolated from the leaves of Ziziphus jujuba (Rhamnaceae).
Gurmarin is a 35-residue polypeptide from the Asclepiad vine Gymnema sylvestre (Gurmar). It has been utilized as a pharmacological tool in the study of sweet-taste transduction because of its ability to selectively inhibit the neural response to sweet taste in rats. This rat inhibition appears to have high specificity to sugar (sweetener) molecules like sucrose, glucose, and saccharin as well as the amino acid glycine. As a sweet-taste-suppressing protein, Gurmarin shows signs of being reversible in nature although having little to no effect on the sweet taste sensation in humans suggesting the protein is only active on rodent sweet taste receptors.
Oleanolic acid or oleanic acid is a naturally occurring pentacyclic triterpenoid related to betulinic acid. It is widely distributed in food and plants where it exists as a free acid or as an aglycone of triterpenoid saponins.
The gustatory system or sense of taste is the sensory system that is partially responsible for the perception of taste (flavor). Taste is the perception stimulated when a substance in the mouth reacts chemically with taste receptor cells located on taste buds in the oral cavity, mostly on the tongue. Taste, along with the sense of smell and trigeminal nerve stimulation, determines flavors of food and other substances. Humans have taste receptors on taste buds and other areas, including the upper surface of the tongue and the epiglottis. The gustatory cortex is responsible for the perception of taste.
Chromium(III) nicotinate is an ionic substance used for chromium supplementation in some nutritional products, where it is also referred to as chromium polynicotinate. It appears in products that are referred to as a medical food used for nutritional support for conditions associated with diabetes mellitus type 2. The product is also known as "niacin-bound chromium".