Brassidic acid: structure and properties

Brassidic acid, a carboxylic acid with a 22 carbon chain, was first prepared from erucic acid by Reimer W. in 1886. In fact, hydrogenation of erucic acid gives behenic acid and, as by-product, brassidic acid.
It belongs to the group of unsaturated fatty acids, with a single trans double bond which originates from position 9 from the methyl end, and is the trans-isomer of erucic acid. Because it is a trans fatty acids, shorthand nomenclature cannot be used to name it. It is a member of the sub-group called very long chain fatty acids or VLCFA, namely, fatty acids with 20 carbon atoms or more.

Molecular weight: 338.56768 g/mol
Molecular formula: C22H42O2
IUPAC name: (E)-docos-13-enoic acid
CAS registry number: 506-33-2
PubChem: 5282772

Skeletal formula of brassidic acid, a trans fatty acid
Brassidic Acid

In purified form it presents as thin, crystalline plates insoluble in water, with melting point at 61-62 °C (141.8-143.6 °F; 334.15-335.15 K) and boiling point at 282 °C (539.6 °F; 555.15 K) at 30 mmHg

(E)-13-docosenoic acid
trans-13-docosenoic acid
13-docosenoic acid, (E)-(8CI)(9CI)


  1. Akoh C.C. and Min D.B. “Food lipids: chemistry, nutrition, and biotechnology” 3th ed. 2008
  2. Chow Ching K. “Fatty acids in foods and their health implication” 3th ed. 2008

Biochemistry, metabolism, and nutrition