Herb's Introduction
Lepisanthes rubiginosa, also known as the rusty sapindus, is a small to medium-sized tree belonging to the Sapindaceae family. This family is well known for a variety of fruits including lychee, longan, and rambutan. The name "rubiginosa" comes from the Latin word "rubiginosus," meaning "rusty," which refers to the rusty-brown hairs found on the young parts of the plant, especially the leaves and stems. The plant is native to tropical and subtropical regions of Asia, including Southeast Asia, India, and China.
Names in Different Countries
This plant goes by many different names depending on the region.
English: Rusty sapindus.
Malay: Buoh terajang, Kalaju, Kelat layu, Ki layu, Kulayo, Mertajam, Terajang.
Thai: ชันรู (Chan ru), หวดคา (Huat kha), หวด ฆ่า (Huat kha), หวด ลาว (Huat lao), กำจำ (Kamcham), กะซ่ำ (Kasam), กำซำ (Kamsam), มะจำ (Ma cham), มะหวด (Ma huat), มะหวด บาท (Ma huat bat), มะหวดลิง (Ma huat ling), มะหวดป่า (Ma huta pa), นำซำ (Nam sam), ซำ (Sam), สีฮอกน้อย (Si hok noi).
Vietnamese: Cây kén kén, Nhãn dê, Nhãn rừng.
Bengali: Kaakjaam.
Terminology and Synonyms
The scientific name is Lepisanthes rubiginosa (Roxb.) Leenh., with "Roxb." referring to the botanist William Roxburgh and "Leenh." to Pieter Leenhouts, who reclassified the species. The family is Sapindaceae.
Some of its synonyms include:
Erioglossum edule (Blume) Blume
Erioglossum rubiginosum (Roxb.) Blume
Sapindus edulis Blume
Sapindus fraxinifolia DC.
Sapindus rubiginosa Roxb.
These synonyms show how the plant has been classified and reclassified over time as botanists better understood its relationships to other plants.
Availability and External Look
Lepisanthes rubiginosa is a tropical plant found in forests, often in secondary and disturbed areas. It can be found in a variety of habitats, including dry forests, swamp forests, and along riverbanks, typically at low altitudes.
The plant can grow as a shrub or a tree, reaching up to 20 meters in height. The leaves are compound, with 2-4 pairs of leaflets that are oblong to elliptic. The leaflets are dark green on top and have a rusty, hairy underside, which gives the plant its name. The flowers are small, fragrant, and yellowish-white, growing in panicles. The fruit is a small, roughly globose to pear-shaped capsule, about 1-2 cm in diameter. It starts off green and turns a rusty red or brownish-red color as it matures. The fruit contains a single seed surrounded by a thin, edible, and somewhat translucent pulp (aril).
Healing Properties and Advantages
Lepisanthes rubiginosa has a long history of traditional medicinal use in various cultures. Its healing properties are attributed to the presence of various bioactive compounds, including flavonoids, alkaloids, and glycosides.
Fever Reduction: In Malaysia, a decoction (a liquid made by boiling a plant part) of the roots is traditionally used to reduce fever.
Skin Diseases: The leaves are applied externally to treat various skin diseases. This suggests anti-inflammatory and antiseptic properties.
Sedative and Hypnotic Effects: In Indonesia, the young stems are consumed to induce sleep. Scientific research has supported this traditional use. An aqueous extract of the fruit's pericarp (the part surrounding the seed) has been shown to have a sedative effect in mice, increasing the time they slept when a sleep-inducing drug was administered.
Dopamine D2 Antagonism: The fruit extract has shown an affinity for dopamine D2 receptors, meaning it can block the action of dopamine at these receptors. This is significant because dopamine D2 antagonists are often used in modern medicine to treat conditions like schizophrenia and other psychotic disorders.
The discovery of a farnesyl glycoside called rubiginoside from the plant highlights its chemical complexity and potential for new drug discoveries.
Uses and Using Way
The primary uses of Lepisanthes rubiginosa are both medicinal and edible.
Edible Fruit: The fruit has a small amount of edible pulp that is sweet and slightly acidic. It is often consumed fresh, though the amount of pulp is limited.
Traditional Medicine:
Fever: A decoction of the roots is prepared by boiling the roots in water and then consuming the liquid.
Skin ailments: The leaves are crushed or pounded into a paste and applied directly to the affected skin.
Insomnia: The young stems are consumed directly, or a preparation from them is ingested to help with sleep.
Ornamental: The plant is sometimes used as an ornamental tree in gardens and parks due to its attractive foliage and fruit.
Timber: The wood is not commercially significant but is sometimes used locally for light construction or firewood.
Conclusion
Lepisanthes rubiginosa is a versatile plant with a rich ethnomedicinal history and potential for modern pharmacological use. While it is known for its small, edible fruit, its primary significance lies in its traditional use for treating fevers, skin ailments, and as a natural sedative. Recent scientific studies have started to validate these traditional uses, identifying specific compounds like rubiginoside and revealing its dopamine D2 receptor antagonism, which opens the door for further research into its potential as a source for new drugs. The plant's widespread availability and multiple uses in different parts of Asia make it a valuable resource for traditional communities and a subject of interest for modern science.
