Purification of conjugated linoleic acid isomers through a process including lipase-catalyzed selective esterification

Abstract

A mixture of conjugated linoleic acids (CLAs) was prepared by alkali conjugation of high purity linoleic acid. The preparation contained 45.1 wt% cis-9, trans-11 (c9, t11)-CLA, 46.8 wt% trans-10, cis-12 (t10, c12)-CLA, and 5.3 wt% other CLAs. A process comprising Candida rugosa lipase-catalyzed selective esterification with lauryl alcohol, molecular distillation, and urea adduct fractionation under strict conditions in ethanol was very effective for purification of c9, t11- and t10, c12-CLAs. In particular, the urea adduct fractionation efficiently eliminated CLAs except c9, t11- and t10, c12-isomers. Purification of c9, t11- and t10, c12-CLAs from 1.0 kg of the CLA mixture increased the c9, t11-CLA purity to 93.1% with 34% recovery of the initial content, and increased the t10, c12-CLA purity to 95.3% with 31% recovery. © 2003 by Japan Society for Bioscience, Biotechnology, and Agrochemistry.