The soapberry is from the sope nut tree (Fam. Sapindaceae), commonly known as Indian filbert. The pericarp of the fruits is a rich source of saponins which are natural surfactants (e.g. detergents). Because the saponins of S. trifoliatus fruits are such mild detergents, they have been used in East Asia and the Himalayas to wash shawls and fine silks. In addition, jewelers have used them for cleaning silver.

 

Traditionally, the soap nut saponins were used as an expectorant, a mild shampoo for the hair, a hair tonic, and as an ingredient for the management of dental caries. Current research conducted on the pharmacological properties of the soap nut saponins of Sapindus species have confirmed its functions as a mild detergent, cleanser, anti-microbial, and anti-inflammatory agent.