Ancistrocladus tectorius (PROSEA)
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Introduction |
Ancistrocladus tectorius (Lour.) Merr.
- Protologue: Lingnan Sci. Journ. 6: 329 (1930).
- Family: Ancistrocladaceae
- Chromosome number: 2n= unknown
Synonyms
Ancistrocladus extensus Wallich ex Planchon (1849), Ancistrocladus pinangianus Wallich ex Planchon (1849).
Vernacular names
- Indonesia: akar bebulus, belulus (Bangka), trung bulus (Belitung)
- Malaysia: akar julong hitam, jenjulong akar, lidah sapi (Peninsular)
- Thailand: kra-maa (Khmer, Saraburi), khon maa (central), li-daa saa-pee (Malay, peninsular)
- Vietnam: trung quân.
Origin and geographic distribution
Burma (Myanmar), Indo-China, southern China, Hainan, the Andaman Islands, Thailand, Peninsular Malaysia, the Riau and Lingga Archipelago, Bangka, Belitung, southern Sumatra and western Borneo.
Uses
In Peninsular Malaysia and Thailand, a decoction of A. tectorius roots is used to treat dysentery and malaria. In Peninsular Malaysia, a decoction of the roots is drunk to improve blood circulation. In Thailand, leaves are used to treat kidney diseases, young leaves are eaten as flavouring, whereas old ones are used for thatching. The stems are sometimes used, e.g. for roofing boats and for arrows.
A. abbreviatus Airy Shaw, endemic in West Africa, is widely used in folk medicine, e.g. against malaria and elephantiasis, and as a laxative; some other species are also used in traditional medicine in Africa.
Properties
Several isoquinoline alkaloids have been isolated from A. tectorius . Tests with bark and leaf extracts confirmed its antimalarial activity. The naphthylisoquinoline alkaloid-containing extracts showed potent growth-inhibiting activity on Plasmodium falciparum and P. berghei in vitro.
Several interesting alkaloids have been isolated from A. korupensis D.W. Thomas & Gereau, native to Cameroon and Nigeria. Michellamines showed more potent antioxidants in assays than several compounds being considered clinically as chemoprevention agents. These compounds and korundamine A demonstrated in-vitro anticytopathic activity against HIV-1. Korundamine A and korupensamines exhibited in-vitro antimalarial activity against Plasmodium falciparum . Extracts and pure naphthylisoquinoline alkaloids derived from the African species A. abbreviatus and A. barteri Scott-Elliot also showed in-vitro antimalarial activity. Furthermore, the triterpene betulinic acid was isolated from the Indian A. heyneanus Wallich ex J. Graham; it was found to exhibit moderate to good in-vitro antimalarial activity against Plasmodium falciparum . In addition, the naphthylisoquinoline alkaloid dioncophylline A isolated from A. abbreviatus showed molluscicidal and fungicidal activities.
Botany
A liana or scandent shrub with tendril-like shoots provided with curved, ultimately woody hooks mostly arranged unilaterally. Leaves alternate, usually crowded above some older hooks, simple and entire, mostly elliptical-obovate, 9-30 cm × 3-10 cm, glabrous, minutely pitted, venation reticulate, sessile; stipules absent. Inflorescence usually between the crowded leaves, dichotomously branched with divaricate, up to 15 cm long branches. Flowers often crowded at the tips of the inflorescence branches, bisexual, regular, 5-merous, small; pedicel articulate; calyx with short tube and 5 unequal lobes enlarged and wing-like in fruit, some or all lobes with prominent glands; petals united at base, obliquely ovate, 3-3.5 mm long; stamens 10, alternately unequal, filaments broadened at base; ovary inferior, 1-celled, protruding into a nipple-shaped elongation bearing 3 articulated styles. Fruit a nut crowned by the much enlarged unequal calyx lobes up to 5 cm × 2 cm. Seed obconical with flat apex, c. 5 mm long; endosperm ruminate. Seedling with epigeal germination; cotyledons thin, leaf-like.
The hook-like structures are modified peduncles. The hooks sometimes have enlarged tips, which are flowers with smaller perianth and reduced stamens and ovary. The leafy branches arise from the axil of hooks.
Ancistrocladus consists of approximately 22 species, 13 of which occur in tropical Africa and 9 in tropical Asia. The affinity of the genus is unclear and it is classified in a separate family. Dipterocarpaceae have most often been suggested as related, mainly because of the rather similar fruits. The occurrence of similar naphthylisoquinoline alkaloids in the African family Dioncophyllaceae has been reason to suggest a phylogenetic link with Ancistrocladaceae . This is also supported by comparative studies of the wood.
Ecology
A. tectorius occurs in mixed forest and scrub vegetation in the lowland, often near the sea, sometimes close to the beach, mostly on siliceous soils.
Genetic resources
A. tectorius is rather widespread and is not very demanding as far as habitat is concerned. It does not seem to be easily liable to genetic erosion.
Prospects
The naphthylisoquinoline alkaloids present in Ancistrocladus proved to be pharmacologically very interesting. Several of these have potent antimalarial activity, indicating a confirmation of the use in traditional medicine against malaria, and, in A. korupensis from Africa, also anti-HIV activity. However, organic and aqueous extracts of A. tectorius have been shown to be inactive in in-vitro anti-HIV assays.
Literature
108, 247, 260, 457.
Other selected sources
121, 282, 596, 643, 705, 731, 800.
Main genus page
Authors
H.C. Ong
