Fatty acid Isomers, Deuterated

Cyclopentyl and cyclohexyl fatty acid monomers are present in heated vegetable oils. Sebedio et al. (1989) have used GC/MS to identify the major products from heated linseed oil as a mixture of 1 1 cis and trans cyclopentyl and cyclohexyl isomers the products of heated sunflower oil were found to be mostly cyclopentyl isomers. The major cyclopentyl isomers were the cis and trans isomers of methyl 7-(2 -hexyl cyclopentyl)-heptanoates and methyl 10-(2 -propylcyclopentyl)-decanoates. The major cyclohexyl isomers were trans and cis methyl 9-(2 -propylcyclohexyl)-nonanoates and made up 50% of the cyclic fatty acid isomers of linseed oil. Dobson et al (1995) have used AgNOs and GC/MS for the structural analysis of cyclic diene fatty acids, and Mossoba et al (1996) have presented confirmatory MS data for cyclic fatty acid monomers by using deuteration. 

Dual-Labeled Technique for Human Lipid Metabolism Studies Involving Deuterated Fatty Acid Isomers 66th Annual Mtg., AOCS, Dallas, Texas... 

The calculation of selectivity values showed that there was discrimination against the incorporation of the deuterated CLA isomers into TAG and CE and a preferential incorporation into PC and phosphatidyl ethanolamine (PE) relative to 9-18 1- /8 and 9, l2-18 2- Q. Comparison of selectivity values for the CLA isomers to r9, l2-18 2- 2 values and values previously reported for c- and r-18 1 positional isomers and 18 0 (17-22) showed that the incorporation of cS,t - and rlO,rl2-CLA matches the r-18 l isomers more than 18 0, 9-18 1, or 9, 12-18 2. This observation is an interesting anomaly since several positive health benefits have been reported for CLA (4), but tram fatty acids (TEA) are considered to have a negative effect on serum cholesterol. Epidemiological studies found a relationship between coronary heart disease risk and dietary intake of TEA from partially hydrated vegetable oils, which mainly contain the t9-, rlO-, and rl 1-18 1 isomers, but no such relationship was found for TEA intake from animal derived foods, whose major TEA isomer is t9-18 1 (vaccenic acid, VA) (19,23,24). 

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