Names | |
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Preferred IUPAC name (13Z)-Docos-13-enoic acid | |
Other names C22:1 (Lipid numbers) | |
Identifiers | |
3D model (JSmol) | |
1728049 | |
ChEBI | |
ChEMBL | |
ChemSpider | |
ECHA InfoCard | 100.003.647 |
EC Number |
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177365 | |
KEGG | |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
| |
| |
Properties | |
C22H42O2 | |
Molar mass | 338.576 g·mol−1 |
Appearance | White waxy solid |
Density | 0.860 g/cm3 |
Melting point | 33.8 °C (92.8 °F; 306.9 K) |
Boiling point | 381.5 °C (718.7 °F; 654.6 K) (decomposes) |
Insoluble | |
Solubility in methanol and ethanol | Soluble |
Hazards | |
GHS labelling: [1] | |
Warning | |
H315, H319, H335 | |
P261, P264, P271, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P403+P233, P405, P501 | |
Flash point | 349.9 °C (661.8 °F; 623.0 K) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Erucic acid is a monounsaturated omega-9 fatty acid, denoted 22:1ω9. It has the chemical formula: CH3(CH2)7CH=CH(CH2)11CO2H. It is prevalent in wallflower seed and other plants in the family Brassicaceae, with a reported content of 20 to 54% in high erucic acid rapeseed oil [2] and 42% in mustard oil. Erucic acid is also known as cis-13-docosenoic acid and the trans isomer is known as brassidic acid.
Erucic acid is a precursor to brassylic acid, a C13-dicarboxylic acid that is used to make specialty polyamides and polyesters. The conversion entails ozonolysis, which selectively cleaves the C=C bond in erucic acid:
Amides of erucic acid are used as lubricants and surfactants. [3]
Hydrogenation of erucic acid gives behenyl alcohol, CH3(CH2)21OH, a pour point depressant (enabling liquids to flow at a lower temperature), and silver behenate, for use in photography. [4]
The name erucic means "of or pertaining to Eruca ", which is a genus of flowering plants in the family Brassicaceae. The genus includes colewort ( E. sativa ), which today is better known as arugula (US) or rocket (UK).
Erucic acid is produced naturally (together with other fatty acids) across a great range of green plants, but especially so in members of the genus Brassica . For industrial purposes and production of erucic acid, rapeseed is used; for food purposes a 'low-erucic acid rapeseed' (LEAR) has been developed (canola), which contains fats derived from oleic acid instead of erucic acid. [3]
Erucic acid is produced by elongation of oleic acid via oleoyl-coenzyme A and malonyl-CoA. [5] Erucic acid is broken down into shorter-chain fatty acids in the human liver by the long-chain acyl CoA dehydrogenase enzyme.
Studies done on laboratory animals in the early 1970s [6] show that erucic acid appears to have toxic effects on the heart at high enough doses. However, more recent research has cast doubt on the relevance of rat studies to the human health of erucic acid. Rats are unusual in their inability to process erucic acid, and the symptoms in rats caused by a diet with high levels of erucic acid have not been observed in pigs, primates, or any other animals. [7] An association between the consumption of rapeseed oil and increased myocardial lipidosis, or heart disease, has not been established for humans. [8] While there are reports of toxicity from long-term use of Lorenzo's oil (which contains erucic acid and other ingredients), there are no reports of harm to people from dietary consumption of erucic acid. [9] : 646–657
Publication of animal studies with erucic acid through the 1970s led to governments worldwide moving away from oils with high levels of erucic acid, [6] and tolerance levels for human exposure to erucic acid have been established based on the animal studies. [8] [10] [11]
In 2003, Food Standards Australia set a provisional tolerable daily intake (PTDI) for an average adult of about 500 mg/day of erucic acid, extrapolated based on "the level that is associated with increased myocardial lipidosis in nursing pigs." [8] "There is a 120-fold safety margin between this level and the level that is associated with increased myocardial lipidosis in nursing pigs. The dietary exposure assessment has concluded that the majority of exposure to erucic acid by the general population would come from the consumption of colza oil. The dietary intake of erucic acid by an individual consuming at the average level is well below the PTDI; therefore, there is no cause for concern in terms of public health and safety. However, the individual consuming at a high level has the potential to approach the PTDI. This would be particularly so if the level of erucic acid in colza oil were to exceed 2% of the total fatty acids." [8]
Food-grade rapeseed oil (also known as canola oil, rapeseed 00 oil, low erucic acid rapeseed oil, LEAR oil, and rapeseed canola-equivalent oil) is regulated to a maximum of 2% erucic acid by weight in the US [10] and 2% in the EU [12] (was 5% [11] before 2019-11-19), with special regulations for infant food. Canola was bred from rapeseed cultivars of B. napus and B. rapa by Dr. Baldur Stefansson at the University of Manitoba, Canada in addition to being cultivated by ancient Chinese, Indian, and Japanese cultures. Canola oil is derived from a variety of rapeseed that is low in erucic acid, as opposed to colza oil.
In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food.
A triglyceride is an ester derived from glycerol and three fatty acids. Triglycerides are the main constituents of body fat in humans and other vertebrates, as well as vegetable fat. They are also present in the blood to enable the bidirectional transference of adipose fat and blood glucose from the liver, and are a major component of human skin oils.
Essential fatty acids, or EFAs, are fatty acids that humans and other animals must ingest because the body requires them for good health, but cannot synthesize them.
α-Linolenic acid, also known as alpha-linolenic acid (ALA), is an n−3, or omega-3, essential fatty acid. ALA is found in many seeds and oils, including flaxseed, walnuts, chia, hemp, and many common vegetable oils.
Vegetable oils, or vegetable fats, are oils extracted from seeds or from other parts of fruits. Like animal fats, vegetable fats are mixtures of triglycerides. Soybean oil, grape seed oil, and cocoa butter are examples of seed oils, or fats from seeds. Olive oil, palm oil, and rice bran oil are examples of fats from other parts of fruits. In common usage, vegetable oil may refer exclusively to vegetable fats which are liquid at room temperature. Vegetable oils are usually edible.
Margarine is a spread used for flavoring, baking, and cooking. It is most often used as a substitute for butter. Although originally made from animal fats, most margarine consumed today is made from vegetable oil. The spread was originally named oleomargarine from Latin for oleum and Greek margarite. The name was later shortened to margarine.
Rapeseed, also known as oilseed rape, is a bright-yellow flowering member of the family Brassicaceae, cultivated mainly for its oil-rich seed, which naturally contains appreciable amounts of erucic acid. The term "canola" denotes a group of rapeseed cultivars that were bred to have very low levels of erucic acid and which are especially prized for use as human and animal food. Rapeseed is the third-largest source of vegetable oil and the second-largest source of protein meal in the world.
Stearic acid is a saturated fatty acid with an 18-carbon chain. The IUPAC name is octadecanoic acid. It is a soft waxy solid with the formula CH3(CH2)16CO2H. The triglyceride derived from three molecules of stearic acid is called stearin. Stearic acid is a prevalent fatty-acid in nature, found in many animal and vegetable fats, but is usually higher in animal fat than vegetable fat. It has a melting point of 69.4 °C and a pKa of 4.50.
Lorenzo's oil is a liquid solution made of 4 parts glycerol trioleate and 1 part glycerol trierucate, which are the triacylglycerol forms of oleic acid and erucic acid. It is prepared from olive oil and rapeseed oil. It is used in the investigational treatment of asymptomatic patients with adrenoleukodystrophy (ALD), a nervous system disorder.
Oleic acid is a fatty acid that occurs naturally in various animal and vegetable fats and oils. It is an odorless, colorless oil, although commercial samples may be yellowish. In chemical terms, oleic acid is classified as a monounsaturated omega-9 fatty acid, abbreviated with a lipid number of 18:1 cis-9, and a main product of Δ9-desaturase. It has the formula CH3−(CH2)7−CH=CH−(CH2)7−COOH. The name derives from the Latin word oleum, which means oil. It is the most common fatty acid in nature. The salts and esters of oleic acid are called oleates. It is a common component of oils, and thus occurs in many types of food, as well as in soap.
Mustard oil can mean either the pressed oil used for cooking, or a pungent essential oil also known as volatile oil of mustard. The essential oil results from grinding mustard seed, mixing the grounds with water, and isolating the resulting volatile oil by distillation. It can also be produced by dry distillation of the seed. Pressed mustard oil is used as cooking oil in some cultures, but sale is restricted in some countries due to high levels of erucic acid. Varieties of mustard seed also exist that are low in erucic acid.
Linoleic acid (LA) is an organic compound with the formula HOOC(CH2)7CH=CHCH2CH=CH(CH2)4CH3. Both alkene groups are cis. It is a fatty acid sometimes denoted 18:2 (n-6) or 18:2 cis-9,12. A linoleate is a salt or ester of this acid.
In biochemistry and nutrition, a monounsaturated fat is a fat that contains a monounsaturated fatty acid (MUFA), a subclass of fatty acid characterized by having a double bond in the fatty acid chain with all of the remaining carbon atoms being single-bonded. By contrast, polyunsaturated fatty acids (PUFAs) have more than one double bond.
Ethyl oleate is a fatty acid ester formed by the condensation of oleic acid and ethanol. It is a colorless oil although degraded samples can appear yellow.
Sunflower oil is the non-volatile oil pressed from the seeds of the sunflower. Sunflower oil is commonly used in food as a frying oil, and in cosmetic formulations as an emollient.
Omega-9 fatty acids are a family of unsaturated fatty acids which have in common a final carbon–carbon double bond in the omega−9 position; that is, the ninth bond from the methyl end of the fatty acid.
Behenic acid is a carboxylic acid, the saturated fatty acid with formula C21H43COOH. In appearance, it consists of white solid although impure samples appear yellowish.
Camelina oil or False flax oil is a pressed seed oil, derived from the Camelina sativa or false flax, also called gold of pleasure. False flax has long been grown in Europe, and its oil used as a lamp oil until the 18th century. In recent times, it has been explored for use in cosmetic and skin care products. It has a high content of omega-3 and is used as a food supplement by some cultures. It is registered under the name "Olej rydzowy tradycyjny" as a Traditional Speciality Guaranteed product in the European Union and the United Kingdom.
Cooking oil is a plant or animal liquid fat used in frying, baking, and other types of cooking. Oil allows higher cooking temperatures than water, making cooking faster and more flavorful, while likewise distributing heat, reducing burning and uneven cooking. It sometimes imparts its own flavor. Cooking oil is also used in food preparation and flavoring not involving heat, such as salad dressings and bread dips.
Rapeseed oil is one of the oldest known vegetable oils. There are both edible and industrial forms produced from rapeseed, the seed of several cultivars of the plant family Brassicaceae. Historically, it was restricted as a food oil due to its content of erucic acid, which in laboratory studies was shown to be damaging to the cardiac muscle of laboratory animals in high quantities and which imparts a bitter taste, and glucosinolates, which made many parts of the plant less nutritious in animal feed. Rapeseed oil from standard cultivars can contain up to 54% erucic acid.