soapbark

American  

[sohp-bahrk] / ˈsoʊpˌbɑrk /

noun

1. a Chilean tree, Quillaja saponaria, of the rose family, having evergreen leaves and small, white flowers.

2. the inner bark of this tree, used as a substitute for soap.

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soapbark British  

/ ˈsəʊpˌbɑːk /

noun

1. Also called: quillai.  a W South American rosaceous tree, Quillaja saponaria, with undivided evergreen leaves and small white flowers

2. Also called: quillai bark.  the inner bark of this tree, formerly used as soap and as a source of saponin

3. any of several trees or shrubs that have a bark similar to this

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Etymology

Origin of soapbark

First recorded in 1860–65; soap + bark ²

Example Sentences

Osbourn had earlier teased out the many enzymatic steps involved in the soapbark tree's production of natural QS-21.

From Science Daily

Earlier this year, Osbourn and Keasling published the complete 20-step process by which the soapbark tree makes QS-21, reconstituted in tobacco.

From Science Daily

A valuable molecule sourced from the soapbark tree and used as a key ingredient in vaccines, has been replicated in an alternative plant host for the first time, opening unprecedented opportunities for the vaccine industry.

From Science Daily

Professor Anne Osbourn FRS, group leader at the John Innes Centre said: "Our study opens unprecedented opportunities for bioengineering vaccine adjuvants. We can now investigate and improve these compounds to promote the human immune response to vaccines and produce QS-21 in a way which does not depend on extraction from the soapbark tree."

From Science Daily

QS-21, a potent adjuvant, is sourced directly from the bark of the soapbark tree, raising concerns about the environmental sustainability of its supply.

From Science Daily