Cinnamaldehyde
Encyclopedia
Cinnamaldehyde is the organic compound
that gives cinnamon
its flavor
and odor
. This pale yellow viscous
liquid occurs naturally in the bark
of cinnamon tree
s and other species of the genus
Cinnamomum
. The essential oil of cinnamon bark is about 90% cinnamaldehyde.
and Péligot
and synthesized in the laboratory by Chiozza in 1854.
The natural product is trans
-cinnamaldehyde. The molecule consists of a phenyl group attached to an unsaturated aldehyde. As such, the molecule can be viewed as a derivative of acrolein
. Its color is due to the π → π* transition: increased conjugation in comparison with acrolein
shifts this band towards the visible.
of the oil of cinnamon bark. The compound can be prepared from related compounds like cinnamyl alcohol
, (the alcohol
form of cinnamaldehyde), but the first synthesis from unrelated compounds was the aldol condensation
of benzaldehyde
and acetaldehyde
.
. All such compounds are biosynthesized starting from phenylalanine
, which undergoes conversion to cinnamoyl ester of coenzyme A.
, ice cream
, candy
, and beverages range from 9 to 4900ppm(parts per million) (that is, less than 0.5%). It is also used in some perfume
s of natural, sweet, or fruit
y scents. Almond
, apricot
, butterscotch
, and other aromas may partially employ the compound for their pleasant smells.
Cinnamaldehyde can be used as a food adulterant; powdered beech
nut husk
aromatized with cinnamaldehyde can be marketed as powdered cinnamon
.
. Proven effective on over 40 different crops
, cinnamaldehyde is typically applied to the root
systems of plants. Its low toxicity
and well-known properties make it ideal for agriculture
. Cinnamaldehyde is an effective insecticide
, and its scent is also known to repel animals like cat
s and dog
s. Cinnamaldehyde has recently been recognized as a very effective insecticide for mosquito
larva
e. As little as 29 ppm (parts per million) of cinnamaldehyde kills half of Aedes aegypti
mosquito larvae in 24 hours.
, prevented oral bacterial growth by more than 50 percent. It is especially effective against bacteria living at the back of the tongue, reducing anaerobic bacteria populations by about 43 percent.
.
for steel
and other ferrous alloy
s in corrosive
fluids. It can be used in combination with additional components such as dispersing agents, solvent
s and other surfactant
s.
of cinnamaldehyde, is used to confer the fragrances of hyacinth and lilac. Cinnamic alcohol (CAS#104-54-1) similarly occurs naturally and has the odor of lilac. Dihydrocinnamaldehyde (CAS#104-53-0) is produced by the selective hydrogenation of the alkene subunit. α-Amyl- and α-hexylcinnamaldehyde are important commercial fragrances, but they are not prepared from cinnamaldehyde.
The level of coumarin
detected in 'cinnamon' extracts and powders has concerned the German BfR.
Organic compound
An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...
that gives cinnamon
Cinnamon
Cinnamon is a spice obtained from the inner bark of several trees from the genus Cinnamomum that is used in both sweet and savoury foods...
its 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...
and odor
Odor
An odor or odour is caused by one or more volatilized chemical compounds, generally at a very low concentration, that humans or other animals perceive by the sense of olfaction. Odors are also commonly called scents, which can refer to both pleasant and unpleasant odors...
. This pale yellow viscous
Viscosity
Viscosity is a measure of the resistance of a fluid which is being deformed by either shear or tensile stress. In everyday terms , viscosity is "thickness" or "internal friction". Thus, water is "thin", having a lower viscosity, while honey is "thick", having a higher viscosity...
liquid occurs naturally in the bark
Bark
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...
of cinnamon tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
s and other species of the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Cinnamomum
Cinnamomum
Cinnamomum is a genus of evergreen aromatic trees and shrubs belonging to the Laurel family, Lauraceae. The species of Cinnamomum have aromatic oils in their leaves and bark. The genus contains over 300 species, distributed in tropical and subtropical regions of North America, Central America,...
. The essential oil of cinnamon bark is about 90% cinnamaldehyde.
Structure and synthesis
Cinnamaldehyde was isolated from cinnamon essential oil in 1834 by DumasJean-Baptiste Dumas
Jean Baptiste André Dumas was a French chemist, best known for his works on organic analysis and synthesis, as well as the determination of atomic weights and molecular weights by measuring vapor densities...
and Péligot
Eugène-Melchior Péligot
Eugène-Melchior Péligot , also known as Eugène Péligot, was a French chemist who isolated the first sample of uranium metal in 1841....
and synthesized in the laboratory by Chiozza in 1854.
The natural product is trans
Geometric isomerism
In organic chemistry, cis/trans isomerism or geometric isomerism or configuration isomerism or E/Z isomerism is a form of stereoisomerism describing the orientation of functional groups within a molecule...
-cinnamaldehyde. The molecule consists of a phenyl group attached to an unsaturated aldehyde. As such, the molecule can be viewed as a derivative of acrolein
Acrolein
Acrolein is the simplest unsaturated aldehyde. It is produced widely but is most often immediately reacted with other products due to its instability and toxicity...
. Its color is due to the π → π* transition: increased conjugation in comparison with acrolein
Acrolein
Acrolein is the simplest unsaturated aldehyde. It is produced widely but is most often immediately reacted with other products due to its instability and toxicity...
shifts this band towards the visible.
Synthesis
Several methods of laboratory synthesis exist, but cinnamaldehyde is most economically obtained from the steam distillationSteam distillation
Steam distillation is a special type of distillation for temperature sensitive materials like natural aromatic compounds....
of the oil of cinnamon bark. The compound can be prepared from related compounds like cinnamyl alcohol
Cinnamyl alcohol
Cinnamyl alcohol is an organic compound that is found in esterified form in storax, balsam Peru and cinnamon leaves. It forms a white crystalline solid when pure, or a yellow oil when even slightly impure. It can be produced by the hydrolysis of storax....
, (the alcohol
Alcohol
In chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....
form of cinnamaldehyde), but the first synthesis from unrelated compounds was the aldol condensation
Aldol condensation
An aldol condensation is an organic reaction in which an enol or an enolate ion reacts with a carbonyl compound to form a β-hydroxyaldehyde or β-hydroxyketone, followed by a dehydration to give a conjugated enone....
of benzaldehyde
Benzaldehyde
Benzaldehyde is an organic compound consisting of a benzene ring with a formyl substituent. It is the simplest aromatic aldehyde and one of the most industrially useful. This colorless liquid has a characteristic pleasant almond-like odor...
and acetaldehyde
Acetaldehyde
Acetaldehyde is an organic chemical compound with the formula CH3CHO or MeCHO. It is one of the most important aldehydes, occurring widely in nature and being produced on a large scale industrially. Acetaldehyde occurs naturally in coffee, bread, and ripe fruit, and is produced by plants as part...
.
Biosynthesis
Cinnamaldehyde occurs widely and closely related compounds give rise to ligninLignin
Lignin or lignen is a complex chemical compound most commonly derived from wood, and an integral part of the secondary cell walls of plants and some algae. The term was introduced in 1819 by de Candolle and is derived from the Latin word lignum, meaning wood...
. All such compounds are biosynthesized starting from phenylalanine
Phenylalanine
Phenylalanine is an α-amino acid with the formula C6H5CH2CHCOOH. This essential amino acid is classified as nonpolar because of the hydrophobic nature of the benzyl side chain. L-Phenylalanine is an electrically neutral amino acid, one of the twenty common amino acids used to biochemically form...
, which undergoes conversion to cinnamoyl ester of coenzyme A.
As a flavorant
The most obvious application for cinnamaldehyde is as flavoring in items like chewing gumChewing gum
Chewing gum is a type of gum traditionally made of chicle, a natural latex product, or synthetic rubber known as polyisobutylene. For economical and quality reasons, many modern chewing gums use rubber instead of chicle...
, ice cream
Ice cream
Ice cream is a frozen dessert usually made from dairy products, such as milk and cream, and often combined with fruits or other ingredients and flavours. Most varieties contain sugar, although some are made with other sweeteners...
, candy
Candy
Candy, specifically sugar candy, is a confection made from a concentrated solution of sugar in water, to which flavorings and colorants are added...
, and beverages range from 9 to 4900ppm(parts per million) (that is, less than 0.5%). It is also used in some perfume
Perfume
Perfume is a mixture of fragrant essential oils and/or aroma compounds, fixatives, and solvents used to give the human body, animals, objects, and living spaces "a pleasant scent"...
s of natural, sweet, or fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
y scents. Almond
Almond
The almond , is a species of tree native to the Middle East and South Asia. Almond is also the name of the edible and widely cultivated seed of this tree...
, apricot
Apricot
The apricot, Prunus armeniaca, is a species of Prunus, classified with the plum in the subgenus Prunus. The native range is somewhat uncertain due to its extensive prehistoric cultivation.- Description :...
, butterscotch
Butterscotch
Butterscotch is a type of confectionery whose primary ingredients are brown sugar and butter, although other ingredients such as corn syrup, cream, vanilla, and salt are part of some recipes...
, and other aromas may partially employ the compound for their pleasant smells.
Cinnamaldehyde can be used as a food adulterant; powdered beech
Beech
Beech is a genus of ten species of deciduous trees in the family Fagaceae, native to temperate Europe, Asia and North America.-Habit:...
nut husk
Husk
Husk in botany is the outer shell or coating of a seed. It often refers to the leafy outer covering of an ear of maize as it grows on the plant. Literally, a husk or hull includes the protective outer covering of a seed, fruit or vegetable...
aromatized with cinnamaldehyde can be marketed as powdered cinnamon
Cinnamon
Cinnamon is a spice obtained from the inner bark of several trees from the genus Cinnamomum that is used in both sweet and savoury foods...
.
As an agrichemical
Cinnamaldehyde is also used as a fungicideFungicide
Fungicides are chemical compounds or biological organisms used to kill or inhibit fungi or fungal spores. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality and profit. Fungicides are used both in agriculture and to fight fungal infections in animals...
. Proven effective on over 40 different crops
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
, cinnamaldehyde is typically applied to the root
Root
In vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...
systems of plants. Its low toxicity
Toxicity
Toxicity is the degree to which a substance can damage a living or non-living organisms. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell or an organ , such as the liver...
and well-known properties make it ideal for agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
. Cinnamaldehyde is an effective insecticide
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...
, and its scent is also known to repel animals like cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
s and dog
Dog
The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...
s. Cinnamaldehyde has recently been recognized as a very effective insecticide for 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...
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. As little as 29 ppm (parts per million) of cinnamaldehyde kills half of 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...
mosquito larvae in 24 hours.
As an antimicrobial
Another use for cinnamaldehyde is as an antimicrobial. Researchers from the University of Illinois at Chicago (who were funded by the Wm. Wrigley Jr. Company) have found that cinnamic aldehyde, when used in Big RedBig Red (gum)
Big Red is a cinnamon-flavored chewing gum introduced by the William Wrigley Jr. Company in 1976.Big Red was available in the UK and Ireland in the mid-to-late 1990s, but is no longer available there . It is a popular souvenir for visitors to the US from Ireland or the UK. Big Red was also...
, prevented oral bacterial growth by more than 50 percent. It is especially effective against bacteria living at the back of the tongue, reducing anaerobic bacteria populations by about 43 percent.
As an anti-cancer agent
Recent research documents anti-cancer activity of cinnamaldehyde/cinnamic aldehyde observed in cell culture and animal models of the disease. Proliferation, invasion, and tumor growth were inhibited in a murine A375 model of human melanomaMelanoma
Melanoma is a malignant tumor of melanocytes. Melanocytes are cells that produce the dark pigment, melanin, which is responsible for the color of skin. They predominantly occur in skin, but are also found in other parts of the body, including the bowel and the eye...
.
Miscellaneous uses
Cinnamaldehyde is also known as a corrosion inhibitorCorrosion inhibitor
A corrosion inhibitor is a chemical compound that, when added to a liquid or gas, decreases the corrosion rate of a material, typically a metal or an alloy. The effectiveness of a corrosion inhibitor depends on fluid composition, quantity of water, and flow regime...
for steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
and other ferrous alloy
Alloy
An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...
s in corrosive
Corrosive
A corrosive substance is one that will destroy or irreversibly damage another surface or substance with which it comes into contact. The main hazards to people include damage to the eyes, the skin, and the tissue under the skin; inhalation or ingestion of a corrosive substance can damage the...
fluids. It can be used in combination with additional components such as dispersing agents, solvent
Solvent
A solvent is a liquid, solid, or gas that dissolves another solid, liquid, or gaseous solute, resulting in a solution that is soluble in a certain volume of solvent at a specified temperature...
s and other surfactant
Surfactant
Surfactants are compounds that lower the surface tension of a liquid, the interfacial tension between two liquids, or that between a liquid and a solid...
s.
Derivatives of cinnamaldehyde
Numerous derivatives of cinnamaldehyde are commercially useful. Dihydrocinnamic alcohol (CAS#122-97-4), which occurs naturally but is produced by double hydrogenationHydrogenation
Hydrogenation, to treat with hydrogen, also a form of chemical reduction, is a chemical reaction between molecular hydrogen and another compound or element, usually in the presence of a catalyst. The process is commonly employed to reduce or saturate organic compounds. Hydrogenation typically...
of cinnamaldehyde, is used to confer the fragrances of hyacinth and lilac. Cinnamic alcohol (CAS#104-54-1) similarly occurs naturally and has the odor of lilac. Dihydrocinnamaldehyde (CAS#104-53-0) is produced by the selective hydrogenation of the alkene subunit. α-Amyl- and α-hexylcinnamaldehyde are important commercial fragrances, but they are not prepared from cinnamaldehyde.
Toxicology
Cinnamaldehyde is used in agriculture because of its low toxicity. It is however a skin irritant.The level of coumarin
Coumarin
Coumarin is a fragrant chemical compound in the benzopyrone chemical class, found in many plants, notably in high concentration in the tonka bean , vanilla grass , sweet woodruff , mullein , sweet grass , cassia cinnamon and sweet clover...
detected in 'cinnamon' extracts and powders has concerned the German BfR.