Effect of fish oil supplementation on the composition of molecular species of choline and ethanolamine glycerophospholipids in ruminant muscle.

Choline glycerophospholipids and ethanolamine glycerophospholipids of ruminant skeletal muscle contain approximately 40% and 65% plasmalogen, respectively. In the 1,2-diacyl-sn-glycero-3-phosphocholine (diacyl CPG), 16:0-18:2(n-6) and 16:0-18:1(n-9) accounted for about 50% of the total molecular species; in the 2-acyl-1(1-alkenyl)-sn-glycero-3-phosphocholine (alkenyl CPG), 16:0-18:2(n-6) was the predominant species. Fish oil supplementation resulted in a sixfold increase in the proportion of 16:0-20:5(n-3) and a two- to threefold increase in the proportion of 18:1-20:5(n-3) and 16:0-22:6(n-3) in the diacyl CPG, and there was a 40% decrease in the proportion of 16:0-18:1(n-9). In the alkenyl CPG, fish oil supplementation increased the proportion of molecular species containing C20 and C22 polyenoic fatty acids from 34% to 64%; in both sheep and cattle, the proportion of 16:0-20:5(n-3) was greater than any other molecular species. In contrast to the diacyl CPG, there was also an increase in the proportion of 18:0-20:5(n-3) in the alkenyl CPG. In the 1,2-diacyl-sn-glycero-3-phosphoethanolamine (diacyl EPG), 18:0-20:4(n-6) represented about 30% of the molecular species and this was reduced to less than 20% by fish oil supplementation.(ABSTRACT TRUNCATED AT 250 WORDS)