Quillaja saponaria

Quillaja saponaria, the soap bark tree or soapbark, is an evergreen tree in the family Quillajaceae, native to warm temperate central Chile. In Chile it occurs from 32 to 40° South Latitude approximately and at up to 2000 m (6500 ft) above sea level. It can grow to 15–20 m (50–65 ft) in height. The tree has thick, dark bark; smooth, leathery, shiny, oval evergreen leaves 3–5 cm long; white star-shaped flowers 15 mm diameter borne in dense corymbs; and a dry fruit with five follicles each containing 10–20 seeds. The tree has several practical and commercial uses.

Habitat

File:Bosque esclerófilo, Chile 001 — Inao Vásquez.jpg

Sclerophyll forests in the Santiago Metropolitan Region in Chile

This tree occurs at elevations up to 2000 metres.<ref>Encyclopedia of the Chilean Flora, 2009</ref> The species is drought resistant, and tolerates about −12 °C (10 °F) in its natural habitat.<ref>J. Taylor. 1990.</ref> Examples of specific occurrences are in central Chile in the forests of La Campana National Park and Cerro La Campana, in which locales it is associated with the Chilean wine palm, Jubaea chilensis.<ref>C. Michael Hogan. 2008</ref> It is often used for reforestation on arid soils.Template:Citation needed

The plant has been introduced as an ornamental in California, and has been acclimatized in Spain but is rarely cultivated there.Template:Citation needed

Etymology

Quillaja is derived from the Chilean vernacular name for this species, culay.<ref name= "gledhill">Gledhill, David (2008). "The Names of Plants". Cambridge University Press. Template:ISBN (hardback), Template:ISBN (paperback). pp 324, 340</ref>

Saponaria means 'soap-like'.<ref name= "gledhill" />

Uses

The wood is used in cabinetry, and scents derived from the tree are used in perfumes and cosmetics. The inner bark of Quillaja saponaria can be reduced to powder and employed as a substitute for soap, since it forms a lather with water, owing to the presence of a glycoside saponin, sometimes distinguished as quillaia saponin. The same, or a closely similar substance, is found in soapwort (Saponaria officinalis), in senega root (Polygala senega) and in sarsaparilla; it appears to be chemically related to digitonin, which occurs in digitalis.

File:Quillaja saponaria UC Berkeley July 2019 by Amber Kerr.jpg

Quillaja saponaria in bloom, University of California, Berkeley, US, July 2019 (by Amber Kerr)

Uses of the saponins

File:Chilean stamps . Medicinal Plants - Quillaja saponaria - Romero (7769410264).jpg

Q. saponaria in a Chilean medicinal plant postage stamp series

{{#invoke:Labelled list hatnote|labelledList|Main article|Main articles|Main page|Main pages}} Soap bark tree has a long history of medicinal use with the Andean people who used it as a treatment for various chest problems.<ref name=":0">Chevallier, A., The Encyclopedia of Medicinal Plants, 1996</ref> The saponin content of the bark helps to stimulate the production of a more watery mucus in the airways, thus facilitating the removal of phlegm through coughing.<ref name=":0" /> The bark is the source of quillaia, the extract of which is used as a food additive and as an ingredient in pharmaceuticals, pesticides, personal care products, fire-fighting foam, and applied as an agricultural spray adjuvant. It is used as an additive in photographic films and as a foaming agent for drinks.

The saponins in Quillaja Extract are also used as the active ingredient in commercial pesticides to inhibit the growth of pathogenic fungi and nematodes in ornamental plants, food crops and turfgrass.<ref>Template:Cite web</ref><ref>Template:Cite web</ref>

The saponins of this tree are also considered to have adjuvant properties for vaccine solutions.<ref name=":1">Singh, Manmohan, 2007. Vaccine Adjuvants and Delivery Systems, page 193</ref> QS21 adjuvant is a saponin obtainable from Quillaja saponaria extract.<ref name=":1" /><ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> The Novavax vaccine for COVID-19 uses this adjuvant,<ref>Template:Cite press release</ref> the zoster vaccine Shingrix also contains QS21 as well as the RSV vaccine Arexvy.<ref>Template:Cite web</ref>

Toxicity

First described by Edwin John Quekett, Q. saponaria wood and bark is known to contain raphides, which George Gulliver found were concentrated along the liber and mesophloeum.Template:Sfn

Sources

• C. Donoso. 2005. Árboles nativos de Chile. Guía de reconocimiento. Edición 4. Marisa Cuneo Ediciones, Valdivia, Chile. 136p.
• Encyclopedia of the Chilean Flora. 2009. Quillaja saponaria
• Template:Cite journal
• Adriana Hoffmann. 1998. Flora Silvestre de Chile, Zona Central. Edición 4. Fundación Claudio Gay, Santiago. 254p.
• C. Michael Hogan. 2008. Chilean Wine Palm: Jubaea chilensis, GlobalTwitcher.com, ed. Nicklas Stromberg
• J. Taylor. 1990. The Milder Garden. Dent
• Chevallier, Andrew, 1996. The Encyclopedia of Medicinal Plants, Dorling Kindersley, 336p.
• Singh, Manmohan, 2007. Vaccine Adjuvants and Delivery Systems, John Wiley & Sons, Hoboken, New Jersey, 457 pp.

External links

• Template:Cite web
• Template:Cite web
• Template:Cite web
• Template:Cite web
• Template:Cite web

{{#if: |

   |{{#ifeq: Soap-bark |
                |{{#ifeq: |
                             |
                             |
                           }}
                |
               }}
  }}{{#ifeq:  |
   |{{#ifeq:  |
                                    |This article
                                    |One or more of the preceding sentences
                                   }} incorporates text from a publication now in the public domain: 
  }}{{#invoke:template wrapper|{{#if:|list|wrap}}|_template=cite EB1911
   |_exclude=footnote, inline, noicon, no-icon, noprescript, no-prescript, _debug

   | noicon=1
  }}{{#ifeq:  ||}}