Sapindus (PROSEA)
Introduction |
Sapindus L.
- Protologue: Sp. pl. 1: 367 (1753); Gen. pl. ed. 5 :171 (1754).
- Family: Sapindaceae
- Chromosome number: x= 11, 15, 18;S. saponaria: 2n= 22, 28, 30, 36,S. trifoliatus: 2n= 36
Origin and geographic distribution
Sapindus comprises 10 species. Continental South-East Asia is richest in species (6). Two species are confined to Central and southern North America, one is endemic to Hawaii and one occurs throughout the tropics and subtropics, partly enhanced by man. In Malesia one species ( S. rarak ) is indigenous, a second ( S. saponaria ) locally naturalized but obviously introduced by man, and a third ( S. trifoliatus L.) occasionally planted as an ornamental.
Uses
Fruits of Sapindus are commonly used in traditional medicine, usually for external applications, e.g. to treat pimples and scabies, and as an insecticide and leech repellent. In India the fruits of S. trifoliatus are used as a remedy for colic, diarrhoea and cholera; an infusion of the fruits is recommended for the treatment of snakebites. Inserted in the nostrils the fruits are said to be a remedy for fits, and a fumigation remedial for hysteria and melancholy. Externally a plaster may be applied to snakebites and swellings. The root may be used as an expectorant and the fruit pulp as a strong purgative.
It appears that the various Sapindus species are more or less used indiscriminately in continental South-East Asia or that they are mutually exchangeable. In Thailand fruits or fruit pulp of S. trifoliatus , pounded in water, are applied as a skin wash or shampoo. The fruit pulp is commonly used as a substitute for soap to wash clothes, e.g. the traditional soga batik of Central Java. The fruits are also employed as a fish poison. The timber of Sapindus is not durable and mostly used for firewood and charcoal only.
Properties
Saponins are found in all plant parts of Sapindus , with the highest concentration in the fruits. Saponins as present in the fruit pericarp of several Sapindus species show strong molluscicidal activity (LC100after 24 h at 5-13 ppm). Extracts also showed potent insecticidal and antifungal activities as well as ichthyotoxic properties.
An extract of S. saponaria totally inhibited the haemorrhagic effect induced by snake venom in a mouse bioassay. The saponins in the fruit pulp of S. trifoliatus showed potent antispermatogenic effects in various test animals. Saponins from the fruit pulp of S. saponaria are one of the 3 ingredients of a polyherbal cream and pessary that has been developed. These ingredients have synergistic spermicidal properties on human sperm, in vitro and in vivo, and a high contraceptive activity in various mammals. Another interesting property of the saponins is their inhibitory action against a wide range of microorganisms, e.g. Candida albicans , Neisseria gonorrhoea , Herpes simplex-2 and HIV-1 viruses. Phase-I clinical trials have been successfully completed in several countries.
Saponins isolated from the fruit pulp of S. rarak showed in-vitro antibacterial activity against Staphylococcus aureus and Streptococcus pyogenes , and antifungal activity against Candida albicans and Candida tropicalis .
The fruit pulp of S. saponaria provides a promising biodegradable surfactant for hexachlorobenzene and naphthalene contaminated soils. A methanol extract of S. rarak fruits, given as a food additive to sheep significantly increased weight gain and digestive efficiency.
Botany
Evergreen, monoecious, small to fairly large trees up to 40 m tall. Leaves arranged spirally, paripinnate, without stipules; leaflets alternate or opposite, entire, herbaceous to leathery. Inflorescence terminal, thyrsoid, widely branched. Flowers unisexual (at least functionally), regular or zygomorphic; sepals 5, free, outer 2 smaller; petals 4-5, equal, as long as or slightly longer than the sepals, short-clawed and with a scale inside; disk annular or semi-annular; stamens 8, free; ovary superior, 3-lobed, 3-celled, strongly reduced in male flowers, style slender. Fruit a 3-lobed schizocarp, but often 1 or 2 parts abortive, breaking up into globular or obovoid drupes, these 1-seeded. Seed globular or ellipsoid, smooth, black.
Ecology
In South-East Asia Sapindus is predominantly found in forests and thickets in monsoon areas at low to medium altitudes.
Management Sapindus is commonly propagated by seed. Pre-treatment with concentrated sulphuric acid or cow-dung slurry is strongly recommended. Chip budding and in-vitro propagation techniques have been practised successfully for S. saponaria .
Genetic resources
Both S. rarak and S. saponaria are widespread and well adapted to disturbed habitats. Moreover, they are widely cultivated and locally naturalized, and thus do not seem to be liable to genetic erosion.
Prospects
Various tests have corroborated the traditional medicinal uses of South-East Asian Sapindus , and most of the activities recorded result from the presence of high concentrations of saponin. Sapindus seems to have promising prospects for the development of modern phytomedicines, especially for external application, having antimicrobial and insecticidal activities. Locally the fruits are highly esteemed as a soap substitute because they are considered to prevent fading of locally produced traditional clothing.
Literature
121, 127, 240, 762, 798, 911.
Selection of species
Authors
Lucie Widowati