Gymnema Health Dictionary

Gymnema sylvestre

Asclepiadaceae

San: Mesasrngi, Madhunasini;

Hin: Gudmar, Merasimgi;

Ben: Merasingi;

Mal: Chakkarakolli, Madhunasini;

Tam: Sirukurumkay, Sakkaraikkolli;

Kan: Kadhasige;

Tel: Podapatra; Mar: Kavali

Importance: Gymnema, Australian Cowplant, Small Indian Ipecacuanha or Periploca of the woods is a woody climber. It is reported to cure cough, dyspnoea, ulcers, pitta, kapha and pain in the eyes. The plant is useful in inflammations, hepatosplenomegaly, dyspepsia, constipation, jaundice, haemorrhoids, strangury, renal and vesical calculi, helminthiasis, cardiopathy, cough, asthma, bronchitis, intermittent fever, amenorrhoea, conjuctivitis and leucoderma. The fresh leaves when chewed have the remarkable property of paralysing the sense of taste for sweet and bitter substance for some time (Warrier et al, 1995). The drug is described as a destroyer of madhumeha (glycosuria) and other urinary disorders. Root has long been reputed as a remedy for snakebite. Leaves triturated and mixed with castor oil are applied to swollen glands and enlargement of internal viscera as the liver and spleen (Nadkarni, 1954). The drug is used to strengthen the function of heart, cure jaundice, piles, urinary calculi, difficult micturition and intermittent fevers (Sharma,1983). The drug enters into the composition of preparations like Ayaskrti, Varunadi kasaya, Varunadighrtam, Mahakalyanakaghrtam, etc. They suppress the activity of taste of tongue for sweet taste and for this reason it was considered that it destroys sugar, hence the name Madhunashini or Gurmar and has been prescribed as an anti-diabetic. The crude drug as well as its dried aqueous extract is mainly used in bronchial troubles.

Distribution: It is a tropical climber. It mainly grows in Western Ghats, Konkan, Tamil Nadu and some parts of Bihar. The plant is cultivated in plains of India but the drug is mainly important from Afghanistan and Iran.

Botany: Gymnema sylvestre (Retz.)R. Br. syn. Asclepias germinata Roxb. belonging to the family Asclepiadaceae is a large, woody much branched climber with pubescent young parts. Leaves are simple, opposite, elliptic or ovate, more or less pubescent on both sides, base rounded or cordate. Flowers are small, yellow and arranged in umbellate cymes. Fruits are slender and follicles are upto 7.5cm long (Warrier et al, 1995).

Two allied species, G. hirsutum found in Bundelkh and Bihar and Western Ghats and G. montanum growing wild in Eastern Ghats and Konkan are also used for the same purpose and are also called “Gurmar” (Thakur et al, 1989).

Agrotechnology: The plant can be propagated both by seeds and stem cuttings. Seedlings are to be raised in polybags. Pits of size 50cm cube are to be taken, filled with 10kg dried cowdung or FYM and covered with topsoil. On these pits about 3-4 months old seedlings are to be transplanted from polybags. Trailing can be facilitated by erecting poles and tying the plants to the poles. The plant will attain good spread within one year. Regular weeding, irrigation and organic manure application are beneficial. The plant is not attacked by any serious pests or diseases. Leaves can be collected from the first year onwards at an internal of one week. This can be continued for 10-12 years. Fresh or dried leaves can be marketed (Prasad et al, 1997).

Properties and activity: Nonacosane and hentriacontane were isolated from the hexane extract of leaves. An attempt to isolate nitrogenous compounds led to the isolation of amino acids such as leucine, iso-leucine, valine, allanine and - amynobutyric acid. Isolation of trimethyl amine oxide was of particular interest. An alkaloid gynamine which is a trace constituent was isolated and identified (Sinsheimer et al, 1967). Antisweet constituent of the leaves has been found to be a mixture of triterpene saponins. These have been designated as gymnemic acids A,B,C and D which have the gymnemagenin and gymnestrogenins as the aglycones of gymnemic acid A and B and gymnemic acid C and D respectively. These are hexahydroxy triterpenes the latter being partially acylated. The sugar residues are glucuronic acid and galacturonic acid while ferulic and angelic acids have been attached as the carboxylic acid.

Chewing of leaves reduces sensitivity to sweet substances. Effects of gymnema extracts had been variable. While verifying the effect of G. sylvestre leaves on detoxification of snake venom, it has been reported that a toxic component of venom ATP and gymnemate bind at the same site inhibiting venom ATP-ase. The active principles which have been identified as glycosides (7 gymnemic acids) suggest that the topical and selective anaesthetic effect of the plant might result from the competition of the receptor sites between glycosides and the sweet substances (Warren et al, 1969). The leaves are antidiabetic and insulinotropic. Gymnemic acid is antiviral. The plant is bitter, astringent, acrid, thermogenic, antiinflammatory, anodyne, digestive, liver tonic, emetic, diuretic, stomachic, stimulant, anthelmintic, alexipharmic, laxative, cardiotonic, expectorant, antipyretic and uterine tonic.