Quillaia is the milled inner bark or small stems and branches of the

soapbark ''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&nb ...

( ''Quillaja saponaria'', Molina). Other names include ''Murillo bark extract'', ''Panama bark extract'', ''Quillaia extract'', ''Quillay bark extract'', and ''Soapbark extract''. Quillaia contains high concentrations of

saponin Saponins (Latin "sapon", soap + "-in", one of), also selectively referred to as triterpene glycosides, are bitter-tasting usually toxic plant-derived organic chemicals that have a foamy quality when agitated in water. They are widely distributed ...

s that can be increased further by processing. Highly purified saponins from quillaia are used as

adjuvants In pharmacology, an adjuvant is a drug or other substance, or a combination of substances, that is used to increase the efficacy#Pharmacology, efficacy or Potency (pharmacology), potency of certain drugs. Specifically, the term can refer to: * Adju ...

to enhance the effectiveness of vaccines. Other compounds in the crude extract include

tannin Tannins (or tannoids) are a class of astringent, polyphenolic biomolecules that bind to and precipitate proteins and various other organic compounds including amino acids and alkaloids. The term ''tannin'' (from Anglo-Norman ''tanner'', ...

s and other

polyphenol Polyphenols () are a large family of naturally occurring organic compounds characterized by multiples of phenol units. They are abundant in plants and structurally diverse. Polyphenols include flavonoids, tannic acid, and ellagitannin, some of ...

s, and

calcium oxalate Calcium oxalate (in archaic terminology, oxalate of lime) is a calcium salt of oxalic acid with the chemical formula . It forms hydrates , where ''n'' varies from 1 to 3. Anhydrous and all hydrated forms are colorless or white. The monohydrate ...

.EFSA Panel on Food Additives and Flavourings (FAF) et al
Re-evaluation of Quillaia extract (E 999) as a food additive and safety of the proposed extension of use.
EFSA Journal. 06 March 2019. Quillaia is used in the manufacture of

food additives Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives have been used for centuries as part of an effort to preserve food, for example vinegar (pickling), salt (salt ...

, and it is listed as an ingredient in

root beer Root beer is a sweet North American soft drink traditionally made using the root bark of the sassafras tree ''Sassafras albidum'' or the vine of ''Smilax ornata'' (known as sarsaparilla, also used to make a soft drink, Sarsaparilla (soft drink ...

and cream soda. The extract also is used as a

humectant A humectant is a hygroscopic (water-absorbing) substance used to keep things moist. They are used in many products, including food, cosmetics, medicines and pesticides. When used as a food additive, a humectant has the effect of keeping moisture ...

in baked goods, frozen dairy products, and puddings and as a

foaming agent A foaming agent is a material such as a surfactant or a blowing agent that facilitates the formation of foam. A surfactant, when present in small amounts, reduces surface tension of a liquid (reduces the work needed to create the foam) or increase ...

soft drink A soft drink (see § Terminology for other names) is a drink that usually contains water (often carbonated), a sweetener, and a natural and/or artificial flavoring. The sweetener may be a sugar, high-fructose corn syrup, fruit juice, a su ...

s. It is used in agriculture for some "natural" spray adjuvant formulations.Biopesticides Registration Action Document
Saponins of Quillaja Saponaria
U.S. Environmental Protection Agency. 11 September 2009.

Saponin adjuvants

The saponins from ''

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&nb ...

'' are used in several approved

veterinary Veterinary medicine is the branch of medicine that deals with the prevention, management, diagnosis, and treatment of disease, disorder, and injury in animals. Along with this, it deals with animal rearing, husbandry, breeding, research on nutri ...

vaccines A vaccine is a biological preparation that provides active acquired immunity The adaptive immune system, also known as the acquired immune system, is a subsystem of the immune system that is composed of specialized, systemic cells and pro ...

(e.g.,

foot-and-mouth disease Foot-and-mouth disease (FMD) or hoof-and-mouth disease (HMD) is an infectious and sometimes fatal viral disease that affects cloven-hoofed animals, including domestic and wild bovids. The virus causes a high fever lasting two to six days, followe ...

vaccines). Initially a crude preparation was used, but more recently purified products have been developed. Two of these (''Quil A'' and ''Matrix-M'') have been shown to be more effective and cause less local

irritation Irritation, in biology and physiology, is a state of inflammation or painful reaction to allergy or cell-lining damage. A stimulus or agent which induces the state of irritation is an irritant. Irritants are typically thought of as chemical age ...

. Sarah Jane Tribble and Rachana Pradhan
Novavax’s Effort to Vaccinate the World, From Zero to Not Quite Warp Speed
Kaiser Health News, Kaiser Family Foundation, July 19, 2021. ''Quil A'' is still a mixture of more than 25 different saponin molecules. One of them, the saponin

QS21 QS-21 is a purified plant extract used as a vaccine adjuvant. It is derived from the soap bark tree (''Quillaja saponaria''), which is native to the countries of Chile, Peru, and Bolivia. The crude drug (''Quillajae cortex'') is imported from ...

, has been investigated for as an adjuvant for human vaccines.

Novavax Novavax, Inc. is an American biotechnology company based in Gaithersburg, Maryland that develops vaccines to counter serious infectious diseases. Prior to 2020, company scientists developed experimental vaccines for influenza and respiratory s ...

uses a highly purified quillaja extract as an adjuvant in its veterinary and human vaccines. The adjuvant, ''Matrix-M'', is made at facilities in Sweden and Denmark.

References

External links

WHO report
Food additives E-number additives {{Ingredient-stub