''Sapindus mukorossi'', commonly known as Indian soapberry, washnut, ritha or Chinese soapberry, is a species of tree in the family

Sapindaceae The Sapindaceae are a family (biology), family of flowering plants in the order Sapindales known as the soapberry family. It contains 138 genera and 1,858 accepted species. Examples include Aesculus, horse chestnut, maples, ackee and lychee. The ...

. It is a deciduous tree that grows in the lower foothills and midhills of the

Himalayas The Himalayas, or Himalaya ( ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the Earth's highest peaks, including the highest, Mount Everest. More than list of h ...

at altitudes of up to . It is also native to western coastal

Karnataka Karnataka ( ) is a States and union territories of India, state in the southwestern region of India. It was Unification of Karnataka, formed as Mysore State on 1 November 1956, with the passage of the States Reorganisation Act, 1956, States Re ...

Maharashtra Maharashtra () is a state in the western peninsular region of India occupying a substantial portion of the Deccan Plateau. It is bordered by the Arabian Sea to the west, the Indian states of Karnataka and Goa to the south, Telangana to th ...

, and

Goa Goa (; ; ) is a state on the southwestern coast of India within the Konkan region, geographically separated from the Deccan highlands by the Western Ghats. It is bound by the Indian states of Maharashtra to the north, and Karnataka to the ...

in India; as well as

Indochina Mainland Southeast Asia (historically known as Indochina and the Indochinese Peninsula) is the continental portion of Southeast Asia. It lies east of the Indian subcontinent and south of Mainland China and is bordered by the Indian Ocean to th ...

southern China Northern China () and Southern China () are two approximate regions that display certain differences in terms of their geography, demographics, economy, and culture. Extent The Qinling–Daba Mountains serve as the transition zone between ...

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

and

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia. The main geography of Taiwan, island of Taiwan, also known as ''Formosa'', lies between the East China Sea, East and South China Seas in the northwestern Pacific Ocea ...

as known by its many indigenous peoples. It is tolerant to reasonably poor soil, can be planted around farmers’ homes,Forestry Nepal (2014). ''Sapindus mukorossi.'' Retrieved from http://www.forestrynepal.org/resources/trees/sapindus-mukorossi and one tree can produce of fruit per year.Poudel, K. L. (2011). Trade potentiality and ecological analysis of NTFPs in Himalayan Kingdom of Nepal. ''Himalayan Research Papers Archives'', 61 . Retrieved from http://hdl.handle.net/1928/3300

Uses

The value of the tree mostly comes from its fruit, which can be used for many pharmacological and cleansing purposes.

Cleanser/insecticide

The soapnut contains the compound of

saponin Saponins (Latin ''sapon'', 'soap' + ''-in'', 'one of') are bitter-tasting, usually toxic plant-derived secondary metabolites. They are organic chemicals that become foamy when agitated in water and have high molecular weight. They are present ...

, which has natural cleansing properties, and therefore the soapnut can be used as a cleanser for hair, skin, and clothing. These saponins are also useful as

insecticide Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. The major use of insecticides is in agriculture, but they are also used in home and garden settings, i ...

s, for purposes such as removing head lice off the scalp.

Surfactant

Methods of extracting the maximum amount of oil from existing oil reserves has become a scientific focus in a world that has become dependent on fossil fuels. Researchers have found that the Ritha fruit can be used in an

enhanced oil recovery Enhanced oil recovery (abbreviated EOR), also called tertiary recovery, is the extraction of crude oil from an oil field that cannot be extracted after primary and secondary recovery methods have been completely exhausted. Whereas primary and se ...

technique. More specifically, Chhetri, Watts, Rahman, and Islam (2009) found that extracts from the soapnut can be used as an organic surfactant to increase the mobility of oil from the fields. In addition, researchers have demonstrated the potential for the soapnut to be used as a natural surfactant for washing arsenic from soils that are rich in iron.

Antimicrobial agent

Due to its saponin content, soapnuts extract may exhibit antibacterial activity. In addition, Grzywaczyk et al. (2023) found that saponins from soapnuts can support the effects of the antibiotics nitrofurantoin or furazolidone against several ''Pseudomonas'' bacteria.

References

{{Taxonbar, from=Q14530198 mukorossi Flora of the Indian subcontinent Flora of Indo-China Saponaceous plants