Erucic acid

Erucic acid is a monounsaturated omega-9 fatty acid, denoted 22:1ω9. It has the chemical formula CH3(CH2)7CH=CH(CH2)11COOH. It is prevalent in wallflower seed with a reported content of 20 to 54% in high erucic acid rapeseed oil, 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 has many of the same uses as mineral oils, but it is more readily biodegradable than some. It has limited ability to polymerize and dry for use in oil paints. Like other fatty acids, it can be converted into surfactants or lubricants, and can be used as a precursor to biodiesel fuel. Derivatives of erucic acid have many further uses, such as behenyl alcohol (CH3(CH2)21OH), a pour point depressant (enabling liquids to flow at a lower temperature), and silver behenate, for use in photography. The name 'erucic' means: of or pertaining to Eruca; which is a genus of flowering plants in the family Brassicaceae. It is also the Latin for colewort, which today is better known as arugula. 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. Erucic acid is produced by elongation of oleic acid via oleoyl-coenzyme A and malonyl-CoA. 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 show that erucic acid appears to have toxic effects on the heart at high enough doses. An association between the consumption of rapeseed oil and increased myocardial lipidosis, or heart disease, has not been established for humans. 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.: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, and tolerance levels for human exposure to erucic acid have been established based on the animal studies.