Docosapentaenoic acid

Docosapentaenoic acid designates any straight chain 22:5 fatty acid.
 * See essential fatty acid for nomenclature.

Two isomers are of particular interest 
 * all-cis-7,10,13,16,19-docosapentaenoic acid is an &omega;-3 fatty acid with the trivial name clupanodonic acid, commonly called DPA. It is an intermediary between eicosapentaenoic acid (EPA, 20:5 ω-3) and docosahexaenoic acid (DHA, 22:6 ω-3). Seal oil is a rich source.
 * all-cis-4,7,10,13,16-docosapentaenoic acid is an &omega;-6 fatty acid with the trivial name Osbond acid.  It is formed by an elongation and desaturation of arachidonic acid 20:4 ω-6.  In mammals, clupanodonic acid deficiency is accompanied by an increase of this isomer; the Osbond/DHA ratio is thus a marker of dietary DHA sufficiency.  However, this usage has been questioned.