A brief study of Sapindus Mukorossi

Sapindus Mukorossi is a fairly large deciduous tree; a member of the family Sapindaceae, It is commonly known as rithha in Nepal and as doda, dodan, and ritha in Indian dialects. Sapindus mukorossi is well known for its folk medicinal values. It is one of the most important trees of tropical and sub-tropical region of Asia. This plant is native to China and Japan, but it is also remarkably scattered to Singapore and India. S. Mukorossi is an ideal tree species for developing forestry bioenergy in a sustainable and multi-production way. It is also commonly called soapberry. One Ritha tree can produce 30–35 kg of fruit per year. It is one of the prioritized medicinal plant for economic development of Nepal.

Fig: Rittha Tree

Botanical Information of Sapindus Mukorossi

S. mukorossi is a deciduous tree that grows well in deep clay loamy soil with an annual rainfall of 150–200 mm (Goyal et al. 2014), and this tree is widely distributed in upper reaches of Indo-Gangetic plains, Shiwaliks and sub-Himalayan region at altitudes from 200 to 1500 m. It usually grows up to height of 12–15 m, but sometimes it attains a height 18–20 m with 1.8 m girth. The bark of this plant is dark to pale yellow, fairly smooth, having many vertical lines of lenticels and fine fissures exfoliating in irregular wood scales. The heartwood is yellowish grey, the sapwood yellowish white. The wood is moderately hard, compact and close-grained.

Leaf: Leaves are 30–50 cm long, alternate, paripinnate and having 5–10 pairs leaflets, opposite or alternate. It has a tapering tip, and is lance-shaped Leaflets are lanceolate, acuminate and 2.5–5 cm in length (Orwa et al. 2009). The appearance of new leaves starts in March, and from April to December, the trees are covered with leaves. Leaves turn yellow in the end of December and start to fall in December–January.  

Flower: Inflorescences are compound terminal panicles about 30 cm long with pubescent

Branches. Flowers are about 5 mm across, polygamous, greenish white, sub sessile, mostly bisexual with five sepals. These are nearly stalkless and numerous in number. It flowers during summer.  The panicles of white or purplish flowers appear in April.

Fruit: The fruit appears in July-August and ripens by November-December. These are solitary, round nuts 2-2.5 cm diameter, fleshy, usually one-seeded drupe, sometimes two drupels together, yellowish brown in color. The seed is enclosed in a black, smooth and hard globose covering. The fruit is collected during winter months for seed and or sale in the market as soap nut. The dried fruit is the most valuable part.

Taxonomical classification of Sapindus Mukorossi:

Biological Name	Sapindus mukorossi
Kingdom	Plantae
Sub kingdom	Tracheobionta
Super division	Spermatophyta
Division	Magnoliophyte
Class	Magnoliopsida
Subclass	Rosidae
Order	Sapindales
Family	Sapindaceae
Genus	Sapindus
Species	Sapindus Mukorossi
Tribe	Andropogoneae
Phylum	Spermatophyta
Sub Phylum	Angiospermae
Common Name	Soapnut, Soapberry, Washnut, Ritha, Aritha, Dodan, Doadni, Doda, Kanma and Thali

Natural Habitat of Sapindus Mukorossi

It is a deciduous plant of the subtropical to the tropical zone, where it can be found at elevations up to 1,500 meters. It requires full sunlight and thrives in nearly any well-drained soil. It is easy to grow by planting seeds in summer. Prefers a deep, fertile, moist soil but plants are very tolerant of a wide range of soils, including those that are dry, stony or nutrient deficient.

Origin and distribution

This plant is native to China as is also called as Chinese soapberry. But it is also a native of Western coastal Maharashtra – Konkan, and Goa in India. Its range is E. Asia - China, Japan, Korea, India, Nepal, Bhutan, Myanmar, Thailand, Cambodia, Vietnam is grown in the lower foothills and mid hills of the Himalayans, up to altitudes of 4000 feet.

These trees are found in wild forests in North West region of Nepal. Districts include Salyan, Dang, Darchula and nearby territories. Distributed scatter rather than colonial from 600 to 1400 m East to West Nepal mostly on open rocky places are found.

Cultivation of Sapindus Mukorossi

It is cultivated, ornamental and wild. The tree is often cultivated in gardens, by temples and along roadsides in China and the Indian subcontinent, both as an ornament and also as a source of soap and as a medicine It is found in areas where the mean annual rainfall is around 1,750mm. Succeeds in a sunny position in any well-drained soil. It prefers a deep, fertile, moist soil, but plants are very tolerant of a wide range of soils, including those that are dry, stony or nutrient deficient. It propagates through seeds. Seeds can remain viable for at least 2 years. About 1-2-year-old seedlings are planted. Owing to low germination capacity and slow germination of seed due to hard covering, the species need to propagate through vegetative means for commercial exploitation. It can propagate vegetative through the cuttings.

Harvesting of Sapindus Mukorossi

The fruit ripening occurs mainly in the November. Fruits may be harvested from 8 to 10 years old trees. The plant has been used by local peoples for thousands of years as a source of saponins that can be used for cleaning clothes etc. It is also harvested from the wild for local use as a food, medicine and source of wood materials.

 

Chemical constituents of Sapindus Mukorossi

The major constituents of Sapindus mukorossi fruit are saponins (10%-11.5%), sugars (10%) and mucilage. Saponins are secondary plant metabolites with divergent biological activities

S. N	Chemical Constituents	Part of plant
1	Triglyceride  Oleo-palmito-arachidin glyceride  Oleo-di-arachidin glyceride  Di-olein	Seed
2	Lipid	Seed
3	Sesquiterpeneoidal gtlycosides	Fruits
4	Flavanoids Quercetin, Apigenin, Kaempferol, Rutin	Leaves
5	Saponin Triterpene  Oleanane (sapindosideA & B)  Dammarane(sapinmusaponin A-E)   tricullane (sapinmusaponin F-K)	Gall, fruit and roots  Fruit Gall Gall and root

Pharmacological Activity of Sapindus Mukorossi

S. N	Activity	Methods used	Part Used
1	Anti-Bacterial activity	Ethanolic and chloroform extracts.	Leaf
2	Spermicidal Activity	Saponins	Fruit Pericarp
3	Anticancer Activity	Saponin from galls extracts	galls
4	Hepatoprotective Activity	Fruit pericarp extract	fruit
5	Molluscicidal Activity	Extract	Fruit
6	Piscicidal Activity		Fruit Pericarp
7	Fungicidal Activity	Crude extract	Pericarp
8	Anti-Inflammatory Activity	Crude extract / isolated saponin and hederagenin	Plant
9	Anti-Platelet Aggregation Activity	Isolation of compounds	Gall
10	Tyrosinase Inhibition and Free Radical Scavenging	Methanolic extract	Seed

Uses of Sapindus Mukorossi

Edible use 

The most edible part of S. mukorossi is seed and its fruits. The seeds are crushed and boiled to make a liquid that is added to certain kinds of Indian milk sweets, known as 'rasgullas'. This adds a frothy quality to the dessert. The seeds have been used to bleach cardamom seeds; this treatment is reported to improve the flavor as well as the color of the spice.

Medicinal

The fruits are of considerable importance for their medicinal value for treating a number of diseases like excessive salivation, pimples, epilepsy, chlorosis, migraines, eczema and psoriasis. The powdered seeds are employed in the treatment of dental caries, arthritis, common colds, constipation and nausea. It is also regarded as a cure for epilepsy in northern India. A decoction of the fruit is used as an expectorant. A lather of the fruit is used to treat burns and also as a soap to wash the hair and rid it of lice. As an Ayurvedic medicine it is used to remove tan and freckles from the skin. It cleanses the skin of oily secretion. The leaves are used in baths to relieve joint pain and the roots are used in the treatment of gout and rheumatism. Since ancient times Sapindus mukorossi has been used as a detergent for shawls and silks.

Agroforestry Uses:

The tree has proved successful in the reforestation of eroded hill slopes at elevations below 900 meters in the western Himalayas. The seed kernels, which are a by-product of the oil extraction from the pericarp and shells, can be used as fertilizer. So, it promotes soil and water conservation, enhance soil fertility, and act as windbreaks for nearby crops

Other Uses

It is also used for restoring and brightening tarnished silverware.

The powdered seeds have insecticidal properties.

 It is used for making furniture, sawing board, plywood, and boards.

The wood is used for fuel and to make charcoal.

A surfactant obtained from the fruit pericarp has proved effective in the remediation of contaminated soils.

Trade in Nepal for Sapindus Mukorossi

Sapindus mukorossi is one of the most traded commodities in terms of MAPs from Nepal. It is either traded in crude form or extractive in the form of oil. It is mostly traded from Nepalgunj, Banke. In the fiscal year 2013/14, about 447.8 tons of Rittha is traded only from Far western development region.

Annually about 450 tones of rittha are exported to India from different village development committees (VDCs) in Darchula DistrictIn 2014–2015, about 233 tonnes of rittha from Gokuleshwor and its neighbouring VDCs were traded, with farmers earning nearly NPR 3.5 million (USD 58,000) at the existing price of NPR 15 (USD 0.25) per kilogram. (ICIMOD 2015)