Sapindus

Sapindus is a genus of about five to twelve species of shrubs and small trees in the Lychee family, Sapindaceae, native to warm temperate to tropical regions in both the Old World and New World. The genus includes both deciduous and evergreen species. Members of the genus are commonly known as soapberries or soapnuts because the fruit pulp is used to make soap. The generic name is derived from the Latin words sapo, meaning "soap", and indicus, meaning "of India".

The leaves are alternate, 15–40 cm (5.9–15.7 in) long, pinnate (except in S. oahuensis, which has simple leaves), with 14-30 leaflets, the terminal leaflet often absent. The flowers form in large panicles, each flower small, creamy white. The fruit is a small leathery-skinned drupe 1–2 cm (0.39–0.79 in) in diameter, yellow ripening blackish, containing one to three seeds.

Uses

The drupes (soapnuts) contain saponins which are a natural surfactant. They have been used for washing for thousands of years by native peoples in Asia as well as Native Americans.