Analysis of Variation in cis-9, trans-11 Conjugated Linoleic Acid (CLA) in Milk Fat of Dairy Cows

摘要

Conjugated linoleic acid (CLA) is a fatty acid with numerous putative health benefits and is a natural com- ponent of ruminant-derived food products. An interme- diate in rumen biohydrogenation is cis-9, trans-11 CLA, the major CLA isomer in milk fat. However, the major source of cis-9, trans-11 CLA in milk is endogenous synthesis by △~9-desaturase conversion of trans-11 C_18:1, another rumen biohydrogenation intermediate. The de- saturease indices serve as a proxy for △~9-desaturase ac- tivity and are calculated from the ratios of fatty acid pairs that represent product/substrate for this enzyme.