Omega-9 fatty acid
Encyclopedia
n−9 fatty acids are a family of unsaturated
fatty acid
s which have in common a final carbon–carbon double bond in the n−9 position; that is, the ninth bond from the end of the fatty acid.
and vegetable oil. Two n−9 fatty acids important in industry are:
Unlike n−3 and n−6 fatty acids, n−9 fatty acids are not classed as essential fatty acids (EFA). This is both because they can be created by the human body from unsaturated fat
, and are therefore not essential in the diet, and because the lack of an n−6 double bond keeps them from participating in the reactions that form the eicosanoid
s.
Under severe conditions of EFA
deprivation, mammals will elongate and desaturate oleic acid to make mead acid
, (20:3, n−9). This also occurs to a lesser extent in vegetarians and semi-vegetarians.
Unsaturated fat
An unsaturated fat is a fat or fatty acid in which there is at least one double bond within the fatty acid chain. A fat molecule is monounsaturated if it contains one double bond, and polyunsaturated if it contains more than one double bond. Where double bonds are formed, hydrogen atoms are...
fatty acid
Fatty acid
In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...
s which have in common a final carbon–carbon double bond in the n−9 position; that is, the ninth bond from the end of the fatty acid.
Background
Some n−9s are common components of animal fatAnimal fat
Animal fats are rendered tissue fats that can be obtained from a variety of animals.- Pet nutrition :In pet nutrition, the source of animal fat concerns food manufacturers. AAFCO states that animal fat is "obtained from the tissues of mammals and/or poultry in the commercial processes of rendering...
and vegetable oil. Two n−9 fatty acids important in industry are:
- Oleic acidOleic acidOleic acid is a monounsaturated omega-9 fatty acid found in various animal and vegetable fats. It has the formula CH37CH=CH7COOH. It is an odorless, colourless oil, although commercial samples may be yellowish. The trans isomer of oleic acid is called elaidic acid...
(18:1, n−9), which is a main component of olive oilOlive oilOlive oil is an oil obtained from the olive , a traditional tree crop of the Mediterranean Basin. It is commonly used in cooking, cosmetics, pharmaceuticals, and soaps and as a fuel for traditional oil lamps...
and other monounsaturated fatMonounsaturated fatIn biochemistry and nutrition, monounsaturated fats or MUFA are fatty acids that have one double bond in the fatty acid chain and all of the remainder of the carbon atoms in the chain are single-bonded...
s - Erucic acidErucic acidErucic acid is a monounsaturated omega-9 fatty acid, denoted 22:1 ω-9. It has the formula CH37CH=CH11COOH. It is prevalent in rapeseed, wallflower seed, and mustard seed, making up 40-50% of their oils...
(22:1, n−9), which is found in rapeseedRapeseedRapeseed , also known as rape, oilseed rape, rapa, rappi, rapaseed is a bright yellow flowering member of the family Brassicaceae...
, wallflowerWallflowerErysimum is a genus that includes about 180 species, both popular garden plants and many wild forms. The genus Cheiranthus is sometimes included herein whole or in part. Erysimum has recently adscribed to a monogeneric cruciferous tribe, Erysimeae...
seed, and mustard seedMustard seedMustard seeds are the small round seeds of various mustard plants. The seeds are usually about 1 or 2 mm in diameter. Mustard seeds may be colored from yellowish white to black. They are important spices in many regional foods. The seeds can come from three different plants: black mustard , brown...
. Rapeseed with high erucic acid content is grown for commercial use in paintings and coatings as a drying oilDrying oilA drying oil is an oil that hardens to a tough, solid film after a period of exposure to air. The oil hardens through a chemical reaction in which the components crosslink by the action of oxygen . Drying oils are a key component of oil paint and some varnishes...
. Rapeseed oil, with some of the acid removed, is commonly known as canola oil.
Unlike n−3 and n−6 fatty acids, n−9 fatty acids are not classed as essential fatty acids (EFA). This is both because they can be created by the human body from unsaturated fat
Unsaturated fat
An unsaturated fat is a fat or fatty acid in which there is at least one double bond within the fatty acid chain. A fat molecule is monounsaturated if it contains one double bond, and polyunsaturated if it contains more than one double bond. Where double bonds are formed, hydrogen atoms are...
, and are therefore not essential in the diet, and because the lack of an n−6 double bond keeps them from participating in the reactions that form the eicosanoid
Eicosanoid
In biochemistry, eicosanoids are signaling molecules made by oxidation of twenty-carbon essential fatty acids, ....
s.
Under severe conditions of EFA
Essential fatty acid
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...
deprivation, mammals will elongate and desaturate oleic acid to make mead acid
Mead acid
Mead acid is an omega-9 fatty acid, first characterized by James F. Mead. Like some other omega-9 polyunsaturated fatty acids animals can make Mead acid de novo. Its elevated presence in the blood is an indication of essential fatty acid deficiency...
, (20:3, n−9). This also occurs to a lesser extent in vegetarians and semi-vegetarians.
List of n−9 fatty acids
| Common name | Lipid name | Chemical name |
|---|---|---|
| oleic acid Oleic acid Oleic acid is a monounsaturated omega-9 fatty acid found in various animal and vegetable fats. It has the formula CH37CH=CH7COOH. It is an odorless, colourless oil, although commercial samples may be yellowish. The trans isomer of oleic acid is called elaidic acid... |
18:1 (n−9) | 9-octadecenoic acid |
| Elaidic acid Elaidic acid Elaidic acid is the major trans fat found in hydrogenated vegetable oils and occurs in small amounts in caprine and bovine milk . It is the trans isomer of oleic acid. The name of the elaidinization reaction comes from elaidic acid.Elaidic acid increases CETP activity, which in turn raises VLDL... |
18:1 (n−9) | (E)-octadec-9-enoic acid |
| eicosenoic acid Eicosenoic acid Eicosenoic acid is a monounsaturated omega-9 fatty acid found in a variety of plant oils.... |
20:1 (n−9) | 11-eicosenoic acid |
| mead acid Mead acid Mead acid is an omega-9 fatty acid, first characterized by James F. Mead. Like some other omega-9 polyunsaturated fatty acids animals can make Mead acid de novo. Its elevated presence in the blood is an indication of essential fatty acid deficiency... |
20:3 (n−9) | 5,8,11-eicosatrienoic acid |
| erucic acid Erucic acid Erucic acid is a monounsaturated omega-9 fatty acid, denoted 22:1 ω-9. It has the formula CH37CH=CH11COOH. It is prevalent in rapeseed, wallflower seed, and mustard seed, making up 40-50% of their oils... |
22:1 (n−9) | 13-docosenoic acid |
| nervonic acid Nervonic acid Nervonic acid is a monounsaturated omega-9 fatty acid. Nervonic acid has been identified as important in the biosynthesis of nerve cell myelin... |
24:1 (n−9) | 15-tetracosenoic acid |
See also
- Polyunsaturated fatty acidPolyunsaturated fatty acidPolyunsaturated fatty acids are fatty acids that contain more than one double bond in their backbone. This class includes many important compounds, such as essential fatty acids and those that give drying oils their characteristic property....
, lists of fatty acids including n−3, n−6, and n−9 fatty acids - n−3 fatty acidOmega-3 fatty acidN−3 fatty acids are essential unsaturated fatty acids with a double bond starting after the third carbon atom from the end of the carbon chain....
- n−6 fatty acidOmega-6 fatty acidn−6 fatty acids are a family of unsaturated fatty acids that have in common a final carbon–carbon double bond in the n−6 position, that is, the sixth bond, counting from the methyl end.The biological effects of the n−6 fatty acids are largely mediated by their conversion to n-6 eicosanoids...