Gelsemium elegans (PROSEA)
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Introduction |
Gelsemium elegans (Gardner & Champ.) Benth.
- Protologue: Journ. Linn. Soc., Bot. 1: 90 (1857).
- Family: Loganiaceae
- Chromosome number: 2n= 16
Synonyms
- Medicia elegans Gardner & Champ. (1849),
- Leptopteris sumatrana Blume (1850),
- Gelsemium sumatranum (Blume) Boerl. (1899).
Vernacular names
- Laos: nguoan dok, nguoan han
- Thailand: ma khet (northern), kok muan (north-eastern)
- Vietnam: lá ngón, thuóc rút ruột, doạn trường thảo.
Origin and geographic distribution
G. elegans is distributed disjunctively from north-eastern India, northern Burma (Myanmar) and Thailand to southern China and Indo-China, Sumatra and northern Borneo.
Uses
All parts of G. elegans, but especially the leaves and the roots are reputed to be poisonous in China as well as Indo-China. Mention is made of its use in murder and suicide. In Chinese traditional medicine the plant is used as an analgesic, antispasmodic and as a remedy for certain kinds of skin ulcers. Externally fresh plant parts or aqueous extracts are applied to various skin afflictions including eczema, boils, ulcers, ringworm as well as in the treatment of haemorrhoids or neuralgic pains.
Production and international trade
G. elegans is only used on a local scale.
Properties
Numerous oxindole and indole-alkaloids have been isolated from G. elegans and G. sempervirens (L.) J. Saint-Hilaire. These include gelsemine, and additional alkaloids such as hydroxydihydrogelsemine, gelsemicine, gelsenicine, gelsevirine, koumine, koumidine, kumantenidine, kumantenine and sempervirine. Fractional amounts of the alkaloids of Gelsemium have a stimulating effect on the central nervous system. The minimum lethal dose of gelsemine in rabbits is 0.1 mg/kg (subcutaneous). Toxic symptoms in humans may vary considerably individually, but in general these will include loss of appetite, stomach upset, internal bleeding, muscle weakness, paralysis of respiration (which will eventually lead to death), heart rate disturbances, hypotensive and and vasodilating effects.
Isolated from a methanolic extract of stems of G. sempervirens, the steroids 12β-hydroxy-5α-pregn-16-ene-3,20-dione and 12β-hydroxy-pregna-4,16-diene-3,20-dione were found to be the main cytotoxic constituents in the KB and P-388 cytotoxicity test systems.
Adulterations and substitutes
Sterile parts of G. elegans are sometimes confused with sterile parts of Jasminum subtriplinerve Blume, a non-poisonous species used as a post-partum medicine and for skin problems in Vietnam.
Description
- A straggling shrub or large woody climber up to 12 m long; twigs glabrous.
- Leaves opposite, simple, entire, ovate-lanceolate, 5-14 cm × 2-5.5 cm, base rounded to decurrent, apex long acuminate; petiole about 1 cm long; stipular lines only.
- Inflorescence a compound thyrse, terminal or axillary, together making a pyramidal leafy panicle; bracteolate; pubescent or glabrous.
- Flower 5-merous, distylous or homostylous; pedicel 0.3-1 cm long; sepals lanceolate, 2-4 mm long, green; corolla tube about 1 cm long, lobes imbricate, blunt to acute, 0.5-1 cm long, bright yellow to orange, throat spotted with red; stamens inserted halfway the tube, 4-8 mm long; ovary superior, oblong to obovoid-lanceolate, 2-2.5 mm long, style 6-12 mm long, stigma 4-fid.
- Fruit a 2-valved, septate, ellipsoidal capsule, 4-10 mm × 3-4 mm, 20-40-seeded.
- Seed reniform to ellipsoid, about 3.5 mm long, warty, surrounded by an irregularly dentate wing.
Growth and development
In Hong Kong G. elegans flowers in November-December, mature fruits are found from March-April.
Other botanical information
In G. elegans short-styled homostylous plants as well as short and long-styled distylous plants are found. North-American G. sempervirens is equally poisonous but widely grown as an ornamental for its fragrant yellow flowers.
Ecology
G. elegans is found in forests and thickets on various soils from 250-2000 m altitude.
Propagation and planting
G. elegans can be easily propagated by seed or semi-ripe cuttings.
Husbandry
In view of its twining habit, G. elegans is suitable for training on trellis and pergolas or for growing on steep banks. Severe pruning after flowering is recommended to retain moderately sized plants.
Harvesting
Roots, twigs and leaves of G. elegans are collected from wild plants whenever needed.
Handling after harvest
In general plant parts of G. elegans are used fresh.
Genetic resources and breeding
G. elegans has a large area of distribution and does not seem to be at risk of genetic erosion.
Prospects
In general, the alkaloids of G. elegans will be too toxic for application. Since little additional information on the phytochemistry and phyto-pharmacology is available, this merits further research to fully evaluate its future potential.
Literature
- Griffin, O. & Parnell, J., 1997. Loganiaceae. In: Santisuk, T. & Larsen, K. (Editors): Flora of Thailand. Vol. 6(3). The Forest Herbarium, Royal Forest Department, Bangkok, Thailand. pp. 197-225.
- Le Tran Duc, 1997. Medicinal plants of Vietnam: cultivation, collection, preparation and therapeutic uses. Agriculture Publishing House, Hanoi, Vietnam. pp. 1340-1342.
- Nguyen Van Duong, 1993. Medicinal plants of Vietnam, Cambodia and Laos. Mekong Printing, Santa Ana, California, United States. pp. 233-234.
- Ornduff, R., 1970. The systematics and breeding system of Gelsemium. Journal of the Arnold Arboretum 50: 1-17.
- Schun, Y. & Cordell, G.A., 1987. Cytotoxic steroids of Gelsemium sempervirens. Journal of Natural Products 50(2): 195-198.
- Tirel-Roudet, C., 1972. Loganiaceae. In: Vidal, J.E. & Galibert, Y. (Editors): Flore du Cambodge, du Laos et du Vietnam [Flora of Cambodia, Laos and Vietnam]. Vol. 13. Muséum National d'Histoire Naturelle, Paris, France. pp. 3-89.
Other selected sources
- [600] Leenhouts, P.W., 1962. Loganiaceae. In: van Steenis, C.G.G.J. (Editor): Flora Malesiana. Series 1, Vol. 6. Wolters-Noordhoff Publishing, Groningen, the Netherlands. pp. 293—387.
- [786] Perry, L.M., 1980. Medicinal plants of East and Southeast Asia. Attributed properties and uses. MIT Press, Cambridge, Massachusetts, United States & London, United Kingdom. 620 pp.
Authors
- Nguyen Tap & Nguyen Kim Bich
