Analysis of fatty acid isomers in ruminant tissues by silver thin layer chromatography followed by gas chromatography

A method for the analysis of trans fatty acids is described in this paper. Separation of trans isomers from the corresponding cis was based on the different facility with which the double bonds in the alkyl chains of both types of fatty acids form polar complexes with silver, and it was carried out by Thin Layer Chromatography (TLC), using silver nitrate impregnated plates. Further separation, identification and quantification of the individual C18:1 isomers, analysed as methyl esters, was carried out by Gas Chromatography (GC). The determination of the content of the isomer t11-C18:1 in ruminant tissues can contribute to try to elucidate the metabolic pathway formation of conjugated linoleic acid (CLA), shown as a fatty acid of beneficial health effects. Furthermore, the analysis of trans fatty acids in other dietary foods seems to be interesting due to their influence on the modification of the serum lipids profile and the role of this type of compounds in human health.