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Anethole
Encyclopedia
Anethole is a phenylpropene
, a type of aromatic compound that occurs widely in nature, in essential oil
s. It contributes a large component of the distinctive flavors of anise
and fennel
(both in the botanical family Apiaceae
), anise myrtle (Myrtaceae
), liquorice (Fabaceae
), and star anise
(Illiciaceae
). Closely related to anethole is its double-bond isomer
estragole
, abundant in tarragon
(Asteraceae
) and basil
(Lamiaceae
), that has a flavor reminiscent of anise. Anethole has numerous commercial uses in multiple industries, and high potential for additional uses.
ether
. It has two cis-trans isomers (see also E-Z notation
), involving the double bond outside the ring. The more abundant isomer, and the one preferred for use, is the trans or E isomer: trans-anethole, t-anethole, (E)-anethole, trans-para-methoxyphenylpropene. Its full chemical name is trans-1-methoxy-4-(prop-1-enyl)benzene.
Anethole is less soluble in water
than in ethanol
, which causes certain anise-flavored liqueur
s to become opaque when diluted with water (see Ouzo effect
). It is a clear, colorless liquid with boiling point
234 °C and congealing point (freezing point
) 20 °C; below its congealing point, anethole forms white crystal
s. The crystals will precipitate from an aqueous solution, which causes a "snow globe
" effect when certain anise-flavored liqueurs are chilled. This effect is the basis of a patent for industrial purification of anethole from sources such as pine oil
. Anethole can be crystallized directly from a source essential oil by lowering the temperature of the oil; adding a crystal of anethole helps to start the process. Historically, this was used to detect adulteration.
. It is perceived as being pleasant to the taste even at higher concentrations. It is unrelated to glycyrrhizic acid, which often co-occurs with it, and also is very sweet. Anethole is used in alcoholic drinks, seasoning and confectionery applications, oral hygiene products, and in small quantities in natural berry flavor
s.
Anethole is an inexpensive chemical precursor for paramethoxyamphetamine (PMA), and used in its clandestine manufacture. Anethole is present in the essential oil from guarana
, which is alleged to have a psychoactive effect; however, the absence of PMA or any other known psychoactive derivative of anethole leads to the conclusion that any purported psychoactive effect of guarana is not due to anethole. Anethole is also present in absinthe
, a liquor with a reputation for psychoactive
effects; these effects however are attributed to ethanol
(see also Thujone
).
Pharmaceutical drugs derived from or related to anethole include anisyldithiolthione, anethole dithione (ADT), and anethole trithione
(ATT).
Anethole is responsible for the "ouzo effect
", the spontaneous formation of a microemulsion
that gives many alcoholic beverages containing anethole and water their cloudy appearance. Such a spontaneous microemulsion has many potential commercial applications in the food and pharmaceutical industries. A derivative of anethole, anethole trithione
, is being investigated for use in self-microemulsifying drug delivery system
s (SMEDDS).
Bacterial strains capable of using trans-anethole as the sole carbon source include JYR-1 (Pseudomonas putida
) and TA13 (Arthrobacter
aurescens). Because they metabolize
anethole into several aromatic chemical compounds, these bacteria are candidates for use in commercial bioconversion
of these valuable compounds from anethole and other phenylpropanoid
s. Compared to other industrial processes, such bioconversion may be less costly and more friendly to the environment.
Anethole has potent antimicrobial
properties, against bacteria
, yeast
, and fungi. Reported antibacterial properties include both bacteriostatic and bactericidal action against Salmonella enterica
but not when used against Salmonella via a fumigation
method. Antifungal activity includes increasing the effectiveness of some other phytochemical
s (e.g. polygodial
) against Saccharomyces cerevisiae
and Candida albicans
; this synergistic effect has potential medical uses.
In vitro
, anethole has antihelmintic action on eggs and larvae of the sheep
gastrointestinal nematode Haemonchus contortus
. Anethole also has nematicidal activity against the plant nematode Meloidogyne javanica
in vitro and in pots of cucumber seedlings.
Anethole also is a promising insecticide. Several essential oils consisting mostly of anethole have insecticidal
action against larva
e of the mosquito
s Ochlerotatus
caspius and Aedes aegypti
. In similar manner, anethole itself is effective against the fungus gnat
Lycoriella ingenua (Sciaridae
) and the mold mite Tyrophagus putrescentiae. Against the mite, anethole is a slightly more effective pesticide
than DEET
but anisaldehyde
, a related natural compound that occurs with anethole in many essential oils, is 14 times more effective. The insecticidal action of anethole is greater as a fumigant
than as a contact agent. (E)-anethole is highly effective as a fumigant against the cockroach
Blattella germanica and against adults of the weevil
s Sitophilus oryzae, Callosobruchus chinensis and beetle
Lasioderma serricorne
.
As well as an insect pesticide, anethole is an effective insect repellent
against
mosquitos.
(GRAS), after a hiatus anethole was reaffirmed by Flavor and Extract Manufacturers Association
(FEMA) as GRAS. The hiatus was due to concerns about liver toxicity and possible carcinogenic activity, reported in rats
. Anethole is associated with a slight increase in liver cancer
in rats, although the evidence is scant and generally regarded as evidence that anethole is not a carcinogen
. An evaluation of anethole by the Joint FAO/WHO Expert Committee on Food Additives
(JECFA) found its notable pharmacologic
properties to be reduction in motor activity, lowering of body temperature
, and hypnotic
, analgesic
, and anticonvulsant
effects. A subsequent evaluation by JECFA found some reason for concern re carcinogenicity but insufficient data. At this time, the JECFA summary of these evaluations is that anethole has no safety concern at current levels of intake when used as a flavoring agent.
In large quantities, anethole is slightly toxic and may act as an irritant.
Phenylpropene
Phenylpropenes, propenylphenols or allylbenzenes are a class of phenylpropanoids, a type of polyphenols.The phenylpropenes, including eugenol, chavicol, safrole and estragole, are derived from the monolignols. These compounds are the primary constituents of various essential oils....
, a type of aromatic compound that occurs widely in nature, in essential oil
Essential oil
An essential oil is a concentrated hydrophobic liquid containing volatile aroma compounds from plants. Essential oils are also known as volatile oils, ethereal oils or aetherolea, or simply as the "oil of" the plant from which they were extracted, such as oil of clove...
s. It contributes a large component of the distinctive flavors of anise
Anise
Anise , Pimpinella anisum, also called aniseed, is a flowering plant in the family Apiaceae native to the eastern Mediterranean region and Southwest Asia. Its flavor resembles that of liquorice, fennel, and tarragon.- Biology :...
and fennel
Fennel
Fennel is a plant species in the genus Foeniculum . It is a member of the family Apiaceae . It is a hardy, perennial, umbelliferous herb, with yellow flowers and feathery leaves...
(both in the botanical family Apiaceae
Apiaceae
The Apiaceae , commonly known as carrot or parsley family, is a group of mostly aromatic plants with hollow stems. The family is large, with more than 3,700 species spread across 434 genera, it is the sixteenth largest family of flowering plants...
), anise myrtle (Myrtaceae
Myrtaceae
The Myrtaceae or Myrtle family are a family of dicotyledon plants, placed within the order Myrtales. Myrtle, clove, guava, feijoa, allspice, and eucalyptus belong here. All species are woody, with essential oils, and flower parts in multiples of four or five...
), liquorice (Fabaceae
Fabaceae
The Fabaceae or Leguminosae, commonly known as the legume, pea, or bean family, is a large and economically important family of flowering plants. The group is the third largest land plant family, behind only the Orchidaceae and Asteraceae, with 730 genera and over 19,400 species...
), and star anise
Star anise
Illicium verum, commonly called Star anise, star aniseed, or Chinese star anise, is a spice that closely resembles anise in flavor, obtained from the star-shaped pericarp of Illicium verum, a small native evergreen tree of northeast Vietnam and southwest China...
(Illiciaceae
Illiciaceae
Illiciaceae is the botanical name of a family of flowering plants. The family has been recognized by most taxonomists, at least for the past several decades....
). Closely related to anethole is its double-bond isomer
Isomer
In chemistry, isomers are compounds with the same molecular formula but different structural formulas. Isomers do not necessarily share similar properties, unless they also have the same functional groups. There are many different classes of isomers, like stereoisomers, enantiomers, geometrical...
estragole
Estragole
Estragole is a phenylpropene, a natural organic compound. Its chemical structure consists of a benzene ring substituted with a methoxy group and a propenyl group. Estragole is a double-bond isomer of anethole. It is a colorless to pale yellow liquid...
, abundant in tarragon
Tarragon
Tarragon or dragon's-wort is a perennial herb in the family Asteraceae related to wormwood. Corresponding to its species name, a common term for the plant is "dragon herb". It is native to a wide area of the Northern Hemisphere from easternmost Europe across central and eastern Asia to India,...
(Asteraceae
Asteraceae
The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...
) and basil
Basil
Basil, or Sweet Basil, is a common name for the culinary herb Ocimum basilicum , of the family Lamiaceae , sometimes known as Saint Joseph's Wort in some English-speaking countries....
(Lamiaceae
Lamiaceae
The mints, taxonomically known as Lamiaceae or Labiatae, are a family of flowering plants. They have traditionally been considered closely related to Verbenaceae, but in the 1990s, phylogenetic studies suggested that many genera classified in Verbenaceae belong instead in Lamiaceae...
), that has a flavor reminiscent of anise. Anethole has numerous commercial uses in multiple industries, and high potential for additional uses.
Structure and properties
In chemical terms, anethole is an aromatic, unsaturatedSaturation (chemistry)
In chemistry, saturation has six different meanings, all based on reaching a maximum capacity...
ether
Ether
Ethers are a class of organic compounds that contain an ether group — an oxygen atom connected to two alkyl or aryl groups — of general formula R–O–R'. A typical example is the solvent and anesthetic diethyl ether, commonly referred to simply as "ether"...
. It has two cis-trans isomers (see also E-Z notation
E-Z notation
E-Z notation, or the E-Z convention, is the IUPAC preferred method of describing the stereochemistry of double bonds in organic chemistry...
), involving the double bond outside the ring. The more abundant isomer, and the one preferred for use, is the trans or E isomer: trans-anethole, t-anethole, (E)-anethole, trans-para-methoxyphenylpropene. Its full chemical name is trans-1-methoxy-4-(prop-1-enyl)benzene.
Anethole is less soluble in water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
than in ethanol
Ethanol
Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...
, which causes certain anise-flavored liqueur
Liqueur
A liqueur is an alcoholic beverage that has been flavored with fruit, herbs, nuts, spices, flowers, or cream and bottled with added sugar. Liqueurs are typically quite sweet; they are usually not aged for long but may have resting periods during their production to allow flavors to marry.The...
s to become opaque when diluted with water (see Ouzo effect
Ouzo effect
The ouzo effect is a phenomenon observed when water is added to ouzo and other anise-flavored liqueurs and spirits, such as pastis, raki, arak and absinthe, forming a milky oil-in-water microemulsion...
). It is a clear, colorless liquid with boiling point
Boiling point
The boiling point of an element or a substance is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid....
234 °C and congealing point (freezing point
Freezing Point
Freezing Point is a news journal in the People's Republic of China which has been the subject of controversy over its criticism of Communist Party officials and the sympathetic ear it lent to a Chinese historian who had criticized official history textbooks...
) 20 °C; below its congealing point, anethole forms white crystal
Crystal
A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...
s. The crystals will precipitate from an aqueous solution, which causes a "snow globe
Snow globe
A snow globe is a transparent sphere, usually made of glass, enclosing a miniaturized scene of some sort, often together with a model of a landscape. The sphere also encloses the water in the globe; the water serves as the medium through which the "snow" falls. To activate the snow, the globe is...
" effect when certain anise-flavored liqueurs are chilled. This effect is the basis of a patent for industrial purification of anethole from sources such as pine oil
Pine oil
Pine oil is an essential oil obtained by the steam distillation of needles, twigs and cones from a variety of species of pine, particularly Pinus sylvestris....
. Anethole can be crystallized directly from a source essential oil by lowering the temperature of the oil; adding a crystal of anethole helps to start the process. Historically, this was used to detect adulteration.
Production
Commercial sources of anethole include some essential oils:Essential oil | World production | trans-anethole |
---|---|---|
Anise | 8 tons (1999) | 95% |
Star anise | 400 tons (1999), mostly from China | 87% |
Fennel | 25 tons (1999), mostly from Spain | 70% |
Uses
Anethole is a flavoring substance of commercial value. In addition, it is distinctly sweet, measuring 13 times sweeter than sugarSugar
Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...
. It is perceived as being pleasant to the taste even at higher concentrations. It is unrelated to glycyrrhizic acid, which often co-occurs with it, and also is very sweet. Anethole is used in alcoholic drinks, seasoning and confectionery applications, oral hygiene products, and in small quantities in natural berry flavor
Flavor
Flavor or flavour is the sensory impression of a food or other substance, and is determined mainly by the chemical senses of taste and smell. The "trigeminal senses", which detect chemical irritants in the mouth and throat as well as temperature and texture, are also very important to the overall...
s.
Anethole is an inexpensive chemical precursor for paramethoxyamphetamine (PMA), and used in its clandestine manufacture. Anethole is present in the essential oil from guarana
Guarana
Guarana , Paullinia cupana, syn. P. crysan, P. sorbilis) is a climbing plant in the maple family, Sapindaceae, native to the Amazon basin and especially common in Brazil. Guarana features large leaves and clusters of flowers, and is best known for its fruit, which is about the size of a coffee bean...
, which is alleged to have a psychoactive effect; however, the absence of PMA or any other known psychoactive derivative of anethole leads to the conclusion that any purported psychoactive effect of guarana is not due to anethole. Anethole is also present in absinthe
Absinthe
Absinthe is historically described as a distilled, highly alcoholic beverage. It is an anise-flavoured spirit derived from herbs, including the flowers and leaves of the herb Artemisia absinthium, commonly referred to as "grande wormwood", together with green anise and sweet fennel...
, a liquor with a reputation for psychoactive
Psychedelics, dissociatives and deliriants
This general group of pharmacological agents can be divided into three broad categories: psychedelics, dissociatives, and deliriants. These classes of psychoactive drugs have in common that they can cause subjective changes in perception, thought, emotion and consciousness...
effects; these effects however are attributed to ethanol
Ethanol
Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...
(see also Thujone
Thujone
Thujone is a ketone and a monoterpene that occurs naturally in two diastereomeric forms: -α-thujone and -β-thujone. It has a menthol odor. Even though it is best known as a chemical compound in the spirit absinthe, recent tests show absinthe contains only small quantities of thujone, and may or may...
).
Pharmaceutical drugs derived from or related to anethole include anisyldithiolthione, anethole dithione (ADT), and anethole trithione
Anethole trithione
Anethole trithione, anetholtrithione, or anetholtrithion is a drug used in the treatment of dry mouth. It is listed in the U.S...
(ATT).
Research
![](http://image.absoluteastronomy.com/images/encyclopediaimages/p/pr/preparing_absinthe.jpg)
Ouzo effect
The ouzo effect is a phenomenon observed when water is added to ouzo and other anise-flavored liqueurs and spirits, such as pastis, raki, arak and absinthe, forming a milky oil-in-water microemulsion...
", the spontaneous formation of a microemulsion
Microemulsion
Microemulsions are clear, thermodynamically stable, isotropic liquid mixtures of oil, water and surfactant, frequently in combination with a cosurfactant. The aqueous phase may contain salt and/or other ingredients, and the "oil" may actually be a complex mixture of different hydrocarbons and olefins...
that gives many alcoholic beverages containing anethole and water their cloudy appearance. Such a spontaneous microemulsion has many potential commercial applications in the food and pharmaceutical industries. A derivative of anethole, anethole trithione
Anethole trithione
Anethole trithione, anetholtrithione, or anetholtrithion is a drug used in the treatment of dry mouth. It is listed in the U.S...
, is being investigated for use in self-microemulsifying drug delivery system
Self-microemulsifying drug delivery system
A self-microemulsifying drug delivery system is a drug delivery system that uses a microemulsion achieved by chemical rather than mechanical means. That is, by an intrinsic property of the drug formulation, rather than by special mixing and handling. It employs the familiar ouzo effect displayed...
s (SMEDDS).
Bacterial strains capable of using trans-anethole as the sole carbon source include JYR-1 (Pseudomonas putida
Pseudomonas putida
Pseudomonas putida is a gram-negative rod-shaped saprotrophic soil bacterium. Based on 16S rRNA analysis, P. putida has been placed in the P. putida group, to which it lends its name....
) and TA13 (Arthrobacter
Arthrobacter
Arthrobacter is a genus of bacteria that is commonly found in soil. All species in this genus are Gram-positive obligate aerobes that are rods during exponential growth and cocci in their stationary phase....
aurescens). Because they metabolize
Metabolism
Metabolism is the set of chemical reactions that happen in the cells of living organisms to sustain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. Metabolism is usually divided into two categories...
anethole into several aromatic chemical compounds, these bacteria are candidates for use in commercial bioconversion
Bioconversion
The term Bioconversion, also known as biotransformation refers to the use of live organisms often microorganisms to carry out a chemical reaction that is more costly or not feasible nonbiologically. These organisms converts a substance to a chemically modified form. An example is the industrial...
of these valuable compounds from anethole and other phenylpropanoid
Phenylpropanoid
The phenylpropanoids are a diverse family of organic compounds that are synthesized by plants from the amino acid phenylalanine. Their name is derived from the six-carbon, aromatic phenyl group and the three-carbon propene tail of cinnamic acid, which is synthesized from phenylalanine in the first...
s. Compared to other industrial processes, such bioconversion may be less costly and more friendly to the environment.
Anethole has potent antimicrobial
Antimicrobial
An anti-microbial is a substance that kills or inhibits the growth of microorganisms such as bacteria, fungi, or protozoans. Antimicrobial drugs either kill microbes or prevent the growth of microbes...
properties, against bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
, yeast
Yeast
Yeasts are eukaryotic micro-organisms classified in the kingdom Fungi, with 1,500 species currently described estimated to be only 1% of all fungal species. Most reproduce asexually by mitosis, and many do so by an asymmetric division process called budding...
, and fungi. Reported antibacterial properties include both bacteriostatic and bactericidal action against Salmonella enterica
Salmonella enterica
Salmonella enterica is a rod-shaped flagellated, facultative anaerobic, Gram-negative bacterium, and a member of the genus Salmonella.- Epidemiology :...
but not when used against Salmonella via a fumigation
Fumigation
Fumigation is a method of pest control that completely fills an area with gaseous pesticides—or fumigants—to suffocate or poison the pests within. It is utilized for control of pests in buildings , soil, grain, and produce, and is also used during processing of goods to be imported or...
method. Antifungal activity includes increasing the effectiveness of some other phytochemical
Phytochemical
Phytochemicals are biologically active chemical compounds that occur naturally in plants . Phytochemicals are the molecules responsible for the color and organoleptic properties . For example, the deep purple color of blueberries and the smell of garlic...
s (e.g. polygodial
Polygodial
Polygodial is an active constituent of Dorrigo Pepper, Mountain Pepper, Horopito, Canelo, Paracress and Water-pepper.Chemically it is a drimane-type sesquiterpene dialdehyde of formula C15H22O2.It elicits a warm and pungent flavour....
) against Saccharomyces cerevisiae
Saccharomyces cerevisiae
Saccharomyces cerevisiae is a species of yeast. It is perhaps the most useful yeast, having been instrumental to baking and brewing since ancient times. It is believed that it was originally isolated from the skin of grapes...
and Candida albicans
Candida albicans
Candida albicans is a diploid fungus that grows both as yeast and filamentous cells and a causal agent of opportunistic oral and genital infections in humans. Systemic fungal infections including those by C...
; this synergistic effect has potential medical uses.
In vitro
In vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
, anethole has antihelmintic action on eggs and larvae of the sheep
Domestic sheep
Sheep are quadrupedal, ruminant mammals typically kept as livestock. Like all ruminants, sheep are members of the order Artiodactyla, the even-toed ungulates. Although the name "sheep" applies to many species in the genus Ovis, in everyday usage it almost always refers to Ovis aries...
gastrointestinal nematode Haemonchus contortus
Haemonchus contortus
Haemonchus contortus, also known as red stomach worm, wire worm or Barber's pole worm, is very common parasite and one the most pathogenic nematode of ruminants. Adult worms are attached to abomasal mucosa and feed on the blood...
. Anethole also has nematicidal activity against the plant nematode Meloidogyne javanica
Meloidogyne javanica
Meloidogyne javanica is a plant pathogenic nematode. It is one of the tropical Root-knot Nematodes and a major agricultural pest in many countries. Meloidogyne javanica reproduces by obligatory mitotic parthenogenesis .- External links :*...
in vitro and in pots of cucumber seedlings.
Anethole also is a promising insecticide. Several essential oils consisting mostly of anethole have insecticidal
Insecticide
An insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
action against larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e of the mosquito
Mosquito
Mosquitoes are members of a family of nematocerid flies: the Culicidae . The word Mosquito is from the Spanish and Portuguese for little fly...
s Ochlerotatus
Ochlerotatus
Ochlerotatus is a genus of mosquito. It was formerly part of Aedes, but now they are two separate genera....
caspius and Aedes aegypti
Aedes aegypti
The yellow fever mosquito, Aedes aegypti is a mosquito that can spread the dengue fever, Chikungunya and yellow fever viruses, and other diseases. The mosquito can be recognized by white markings on legs and a marking in the form of a lyre on the thorax...
. In similar manner, anethole itself is effective against the fungus gnat
Fungus gnat
Fungus gnats are small, dark, short-lived flies, of the families Sciaridae, Diadocidiidae, Ditomyiidae, Keroplatidae, Bolitophilidae and Mycetophilidae , sometimes placed in the superfamily Mycetophiloidea, whose larvae feed on plant roots or fungi and aid in the decomposition of organic matter...
Lycoriella ingenua (Sciaridae
Sciaridae
Sciaridae is a family of flies, commonly known as dark-winged fungus gnats. Commonly found in moist environments, they are known to be a pest of mushroom farms and are commonly found in household plant pots. This is one of the least studied of the large Diptera families, probably due to the small...
) and the mold mite Tyrophagus putrescentiae. Against the mite, anethole is a slightly more effective pesticide
Pesticide
Pesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.A pesticide may be a chemical unicycle, biological agent , antimicrobial, disinfectant or device used against any pest...
than DEET
DEET
N,N-Diethyl-meta-toluamide, abbreviated DEET, is a slightly yellow oil. It is the most common active ingredient in insect repellents...
but anisaldehyde
Anisaldehyde
Anisaldehyde, or anisic aldehyde, is an organic compound that consists of a benzene ring substituted with an aldehyde and a methoxy group. It is a clear colorless liquid with a strong aroma. It comes in 3 varieties, ortho, meta, and para in which the two functional groups are alpha, beta, and...
, a related natural compound that occurs with anethole in many essential oils, is 14 times more effective. The insecticidal action of anethole is greater as a fumigant
Fumigation
Fumigation is a method of pest control that completely fills an area with gaseous pesticides—or fumigants—to suffocate or poison the pests within. It is utilized for control of pests in buildings , soil, grain, and produce, and is also used during processing of goods to be imported or...
than as a contact agent. (E)-anethole is highly effective as a fumigant against the cockroach
Cockroach
Cockroaches are insects of the order Blattaria or Blattodea, of which about 30 species out of 4,500 total are associated with human habitations...
Blattella germanica and against adults of the weevil
Weevil
A weevil is any beetle from the Curculionoidea superfamily. They are usually small, less than , and herbivorous. There are over 60,000 species in several families, mostly in the family Curculionidae...
s Sitophilus oryzae, Callosobruchus chinensis and beetle
Beetle
Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...
Lasioderma serricorne
Lasioderma serricorne
Lasioderma serricorne, commonly known as the cigarette beetle, cigar beetle, or tobacco beetle, is very similar in appearance to the drugstore beetle and the common furniture beetle , and all three species belong to the family Anobiidae.L. serricorne is around 2–3 mm long, and brown in colour...
.
As well as an insect pesticide, anethole is an effective insect repellent
Insect repellent
An insect repellent is a substance applied to skin, clothing, or other surfaces which discourages insects from landing or climbing on that surface. There are also insect repellent products available based on sound production, particularly ultrasound...
against
mosquitos.
Safety
Formerly generally recognized as safeGenerally recognized as safe
Generally recognized as safe is an American Food and Drug Administration designation that a chemical or substance added to food is considered safe by experts, and so is exempted from the usual Federal Food, Drug, and Cosmetic Act food additive tolerance requirements.-History:On January 1, 1958,...
(GRAS), after a hiatus anethole was reaffirmed by Flavor and Extract Manufacturers Association
Flavor and Extract Manufacturers Association
The Flavor and Extract Manufacturers Association of the United States was founded in 1909 by several flavor firms in response to the passage of the Pure Food and Drug Act of 1906. Founding members were McCormick & Company, Ulman Driefus & Company, Jones Brothers, Blanke Baer Chemical Company,...
(FEMA) as GRAS. The hiatus was due to concerns about liver toxicity and possible carcinogenic activity, reported in rats
RATS
RATS may refer to:* RATS , Regression Analysis of Time Series, a statistical package* Rough Auditing Tool for Security, a computer program...
. Anethole is associated with a slight increase in liver cancer
Liver cancer
Liver tumors or hepatic tumors are tumors or growths on or in the liver . Several distinct types of tumors can develop in the liver because the liver is made up of various cell types. These growths can be benign or malignant...
in rats, although the evidence is scant and generally regarded as evidence that anethole is not a carcinogen
Carcinogen
A carcinogen is any substance, radionuclide, or radiation that is an agent directly involved in causing cancer. This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes...
. An evaluation of anethole by the Joint FAO/WHO Expert Committee on Food Additives
Joint FAO/WHO Expert Committee on Food Additives
The Joint FAO/WHO Expert Committee on Food Additives is a scientific expert committee that is jointly run by the United Nations Food and Agriculture Organization and the World Health Organization....
(JECFA) found its notable pharmacologic
Pharmacology
Pharmacology is the branch of medicine and biology concerned with the study of drug action. More specifically, it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function...
properties to be reduction in motor activity, lowering of body temperature
Normal human body temperature
Normal human body temperature, also known as normothermia or euthermia, is a concept that depends upon the place in the body at which the measurement is made, and the time of day and level of activity of the person...
, and hypnotic
Hypnotic
Hypnotic drugs are a class of psychoactives whose primary function is to induce sleep and to be used in the treatment of insomnia and in surgical anesthesia...
, analgesic
Analgesic
An analgesic is any member of the group of drugs used to relieve pain . The word analgesic derives from Greek an- and algos ....
, and anticonvulsant
Anticonvulsant
The anticonvulsants are a diverse group of pharmaceuticals used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of bipolar disorder, since many seem to act as mood stabilizers, and in the treatment of neuropathic pain. The goal of an...
effects. A subsequent evaluation by JECFA found some reason for concern re carcinogenicity but insufficient data. At this time, the JECFA summary of these evaluations is that anethole has no safety concern at current levels of intake when used as a flavoring agent.
In large quantities, anethole is slightly toxic and may act as an irritant.
See also
- :Category:Anise liqueurs and spirits
- List of liqueurs#Anise-flavored liqueurs
- ChavicolChavicolChavicol, or p-allylphenol, is a natural phenylpropene, a type of organic compound. Its chemical structure consists of a benzene ring substituted with a hydroxy group and a propenyl group. It is a colorless liquid found together with terpenes in betel oil. It is miscible with alcohol, ether, and...
- SafroleSafroleSafrole, also known as shikimol, is a phenylpropene. It is a colorless or slightly yellow oily liquid. It is typically extracted from the root-bark or the fruit of sassafras plants in the form of sassafras oil , or synthesized from other related methylenedioxy...
- FenchoneFenchoneFenchone is a natural organic compound classified as a monoterpene and a ketone. It is a colorless oily liquid. It has a structure and an odor similar to camphor.Fenchone is a constituent of absinthe and the essential oil of fennel....