Estragole (''p''-allylanisole, methyl chavicol) is a

phenylpropene Phenylpropene is the organic compound with the formula C6H5CH2CH=CH2. It is a colorless liquid. The compound consists of a phenyl group attached to allyl. Phenylpropene isomerizes to trans-propenylbenzene. In plant biochemistry, the phenylprop ...

, a natural organic compound. Its chemical structure consists of a benzene ring substituted with a

methoxy group In organic chemistry, a methoxy group is the functional group consisting of a methyl group bound to oxygen. This alkoxy group has the formula . On a benzene ring, the Hammett equation classifies a methoxy substituent at the ''para'' position as ...

and an

allyl In organic chemistry, an allyl group is a substituent with the structural formula , where R is the rest of the molecule. It consists of a methylene bridge () attached to a vinyl group (). The name is derived from the scientific name for garlic, ...

group. It is an isomer of

anethole Anethole (also known as anise camphor) is an organic compound that is widely used as a flavoring substance. It is a derivative of phenylpropene, a type of aromatic compound that occurs widely in nature, in essential oils. It is in the class of p ...

, differing with respect to the location of the double bond. It is a colorless liquid, although impure samples can appear yellow. It is a component of various trees and plants, including turpentine (pine oil),

anise Anise (; '), also called aniseed or rarely anix is a flowering plant in the family Apiaceae native to Eurasia. The flavor and aroma of its seeds have similarities with some other spices and herbs, such as star anise, fennel, licorice, and ta ...

, fennel,

bay A bay is a recessed, coastal body of water that directly connects to a larger main body of water, such as an ocean, a lake, or another bay. A large bay is usually called a Gulf (geography), gulf, sea, sound (geography), sound, or bight (geogra ...

, tarragon, and basil. It is used in the preparation of fragrances.. The compound is named for ''estragon'', the French name of tarragon.

Production

Hundreds of tonnes of basil oil are produced annually by steam distillation of '' Ocimum basilicum'' (common basil). This oil is mainly estragole but also contains substantial amounts of linalool. Estragole is the primary constituent of

essential oil An essential oil is a concentrated hydrophobic liquid containing volatile (easily evaporated at normal temperatures) chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the o ...

of tarragon (comprising 60–75%). It is also present in pine oil, turpentine, fennel,

(2%), ''

Clausena anisata :''Should not be confused with syzygium anisatum, a tree native to eastern Australian rainforests, used as a culinary herb.'' ''Clausena anisata'' (Willd.) Hook.f. ex Benth. is a deciduous shrub or small tree, belonging to the Rutaceae or Citrus ...

'' and ''

Syzygium anisatum :''Should not be confused with Clausena anisata, a small tree native to Southeast Asia and Australia.'' ''Syzygium anisatum'', with common names ringwood and aniseed tree, is a rare Australian rainforest tree with an aromatic leaf that has an ...

''. Estragole is used in perfumes and is restricted in flavours as a biologically active principle: it can only be present in a flavour by using an essential oil. Upon treatment with potassium hydroxide, estragole converts to

. A known use of estragole is in the synthesis of magnolol.

Safety

Estragole is suspected to be carcinogenic and genotoxic, as is indicated by a report of the European Union Committee on Herbal Medicinal Products.EMEA/HMPC/137212/2005, Committee on Herbal Medicinal Products. Final Public Statement on the Use of Herbal Medicinal Products Containing Estragole http://www.ema.europa.eu/docs/en_GB/document_library/Scientific_guideline/2010/04/WC500089960.pdf Several studies have clearly established that the profiles of metabolism, metabolic activation, and covalent binding are dose dependent and that the relative importance diminishes markedly at low levels of exposure (that is, these events are not linear with respect to dose). In particular, rodent studies show that these events are minimal probably in the dose range of 1–10 mg/kg body weight, which is approximately 100 to 1,000 times the anticipated human exposure to this substance. For these reasons it is concluded that the present exposure to estragole resulting from consumption of herbal medicinal products (short time use in adults at recommended posology) does not pose a significant cancer risk. In the meantime exposure of estragole to sensitive groups such as young children, pregnant and breastfeeding women should be minimized. The Scientific Committee on Food from the Health and Consumer Protection Directorate took a more concerned position and concluded that "Estragole has been demonstrated to be genotoxic and carcinogenic. Therefore the existence of a threshold cannot be assumed and the Committee could not establish a safe exposure limit. Consequently, reductions in exposure and restrictions in use levels are indicated."SCF/CS/FLAV/FLAVOUR/6, 26 September 2001, Opinion of the Scientific Committee on Food on Estragole (1-Allyl-4-methoxybenzene)

References

External links

Opinion by the Scientific Committee on Food of the European Union on Estragole
{{Phenylpropene Food additives Perfume ingredients Phenylpropenes Phenol ethers Allyl compounds O-methylated natural phenols

Production

Safety

See also

References

External links