Conjugated linoleic acid isomer enrichment

McNeill, GP, Rawlins, C and Peilow, AC (1999) Enzymatic enrichment of conjugated linoleic acid isomers and incorporation into triglycerides. J. Am. Oil Chem. Soc., 76, 1265-1268. 

Over the last two decades, the conjugated fats and, particularly, conjugated linoleic acid (CLA) have been intensively studied for their biological activity. As a result of the ease of synthesis, blends of two CLA isomers, namely 9,11-ct and 10,12-tc-CLA, have been the focus of most research into biological activity. Recent research, however, has been expanding to include pure or enriched isomer preparations. 

Kim, Y.J., Liu, R.H., Rychlik, J.L., and Russell, J.B. 2002. The enrichment of a ruminal bacterium (Megasphaera elsdenii YJ-4) that produces the trans-10, cis-12 isomer of conjugated linoleic acid. 

Isomers of conjugated linoleic acids (CLA) have anticancer activity, and immnne-enhancing-weight reductions, and antiatherogenic properties. CLA are fonnd in food prodnced from ruminant animals. The development of CLA-enriched eggs showed a redaction in monoenoic FA and non-CLA PUFA after CLA feeding, and an increase in ERA and DHA. The incorporation rates of different CLA isomers into the whole lipids of egg yolk and TAG, PC, and PE-lipid classes were different. cis-9,trans-ll and cis-l0,trans-l2 CLA were deposited more in TAG, bnt cis-11,trans-l3 CLA was less. There are large differences in the concentrations of cis-8,trans-10 CLA in PC and PE (Table 14.10C). 

CLA and their metabolites have been shown to be incorporated mainly into neutral lipids from different tissues (Table 15.1). This shows that for acylation, CLA is behaving more like oleic acid than like linoleic acid. When fed in the same quantity, more 9c,llt-isomer than lOt, 12c-18 2 was found in the different tissues studied. Similarly, very few CLA metabolites were incorporated into the phospholipids (Table 15.2). On the contrary, using diets low in essential fatty acids (butter fat), Banni et al. (4) demonstrated that the conjugated arachidonic acid was enriched predominantly in phosphatidylserine and phosphatidylinositol. On the contrary, arachidonic acid was incorporated mainly into phosphatidylcholine and to a lesser extent into phosphatidylethanolamine. In mice, even using diets equilibrated in essential fatty acids, lOt, 12c-18 2 was shown to be converted into conjugated arachidonic acid (Table 15.3). This metabolite was incorporated preferentially into phospholipids, thus confirming the data of Banni et al (4). 

Jerome, D and Skarie, C (ConUnCo) (2001a) Method of using isomer enriched conjugated linoleic acid compositions. US Patent 6,214,372. 

Bessa, R. J. B., Santos-Silva, J., Ribeiro, J. M. R., Portugal, A. V. (2000). Reticulo-rumen biohydrogenation and the enrichment of ruminant edible products with linoleic acid conjugated isomers. Livestock Production Science, 63, 201-211. 

The metabolites formed depend on the type of fatty acids present in the diet (Fig. 15.1). When fed to rats along with a diet deficient in both linoleic and Unolenic acids, both CLA isomers are transformed into conjugated isomers of arachidonic acid. Again the conjugated 20 4 metabolite was also found in liver of rats fed a high or low CLA-enriched butter fat, which are diets containing low quantities of essential fatty acids (3). In tissues of rats fed an equilibrated diet and either pure or mixtures of CLA isomers, the 9c,llf isomer was converted mainly into 8c,llc,13f-20 3, whereas the 10f,12c-18 2 was converted into 6c,10f,12c-18 3 and into 6,10c-16 2. Banni et al. (4) also reported the presence of 8c,llc,13t-20 3 as the major CLA metabolite in liver lipids of rats fed either a low or high CLA-enriched butter fat diet, both of which... 

---