Erucic acid

Uses

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:

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Amides of erucic acid are used as lubricants and surfactants.

Hydrogenation of erucic acid gives behenyl alcohol, , a pour point depressant (enabling liquids to flow at a lower temperature), and which can be made into silver behenate, for use in photography.

Sources of erucic acid

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.

Biochemistry

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.

Health effects

As early as 1977, the use of rapeseed oil was deemed safe as a food additive in the United States.

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." "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 (rapeseed oil, but not from the cultivar developed to produce canola 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."

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 and Europe.

References

References

1. "Erucic acid".
2. Sahasrabudhe, M. R.. (1977). "Crismer values and erucic acid contents of rapeseed oils". Journal of the American Oil Chemists' Society.
3. Economic Research Service, USDA. (1996). "Crambe, Industrial Rapeseed, and Tung Provide Valuable Oils". Fats and Oils, Industrial Uses.
4. (2006). "Ullmann's Encyclopedia of Industrial Chemistry".
5. (1998). "The Biosynthesis of Erucic Acid in Developing Embryos of Brassica rapa". Plant Physiol.
6. U.S. Dept. of Health and Human Services, [https://web.archive.org/web/20030510181406/http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?FR=184.1555 CFR – Code of Federal Regulations Title 21] 1 April 2010.
7. Food Standards Australia New Zealand (June 2003) [http://www.foodstandards.gov.au/publications/documents/Erucic%20acid%20monograph.pdf Erucic acid in food: A Toxicological Review and Risk Assessment] {{Webarchive. link. (23 November 2018 Technical report series No. 21; Page 4 paragraph 1; {{ISBN). 0-642-34526-0, ISSN 1448-3017
8. "EUR-Lex – 32019R1870R(01) – EN – EUR-Lex".