Composition of diacyl glyceryl ethers in the liver lipids of ratfish, Hydrolagus novaezealandiae.

The diacyl glyceryl ether composition of the liver lipids of deep-sea ratfish, Hydrolagus novaezealandiae, was investigated. The liver of this deep-sea ratfish yielded high lipid content (64.1%), of which neutral lipids were the predominant classes accounting for more than 99% of the total lipid content. This is in contrast with the muscle lipids which yielded a low lipid content (0.7%), of which phospholipids accounted for 78%. The amount of diacyl glyceryl ethers (65.8%) was much greater than that of triglycerides (10.4%) in the liver lipids. The component glyceryl ethers of diacyl glyceryl ethers were found to consist mostly of saturates (29.3%) and monoenes (66.9%) of 14-22 carbon atoms for the alkyl moiety. The principle components found were 18:1 (51.2%), 16:0 (14.9%), 18:0 (9.6%), and 16:1 (8.7%). The fatty acid composition of diacyl glyceryl ethers from liver lipids was similar to that of triglycerides which consist mainly of monoenoic acids having 18:1 acid as its predominant component. In contrast, those of the neutral lipids and phospholipids of the muscle contained considerable amounts of polyenoic acids in which 22:6 acid was found to be the predominant component.