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

Abstract

The diacyl glyceryl ether composition of the liver lipids of deep-sea ratfish, Hydrolagus novaezea landiae, 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 com ponent. In contrast, those of the neutral lipids and phospholipids of the muscle contained con siderable amounts of polyenoic acids in which 22:6 acid was found to be the predominant com ponent. Diacyl glyceryl ethers are widely distributed in the various organs of marine organisms but are present only in appreciable amounts1). However, some kinds of shark, belonging to the Subclass Elasmobranchii, are known to possess liver lipids which are chiefly composed of these compounds2-6. Recently, several peculiar species of marine teleost

Seasonal changes in phospholipids of mussel (Mytilus edulis Linne)

“…The highest amount appeared in autumn and the lowest in summer and winter. This accords with the conclusion that neutral lipids serve as an energy store 9…”

Lipids and buoyancy in Southern Ocean pteropods

“…The dogfish, Squalus acanthias, has 38-45% DAGE in the liver oil, and the holocephalans Chimaera barbouri, C. ogilbye, and Hydrolagus colliei have more than 50% DAGE in the liver oil (3). Hydrolagus novaezealandiae has 66% DAGE in its liver oil (26). Methoxyglyceryl ethers, first isolated from Greenland shark liver lipids, have antibiotic activity and inhibit the growth of tumors in mice (27).…”

Buoyancy in Marine Fishes: Direct and Indirect Role of Lipids

“…The dogfish (Squalus acanthias) has 38-45% DAGE in the liver oil and other Squalus species may have up to 54% DAGE (Sargent, 1989). The holocephalans Hydrolagus colliei, Chimaera barbouri, and C. ogilbye have more than 50% DAGE in their liver oil (Sargent, 1989) and H. novaezealandiae has 66% DAGE in its liver oil (Hayashi and Takagi, 1980). Methoxy-glyceryl ethers, first isolated from the lipid of the liver of Greenland shark, account for 0.1-0.3% of liver lipid in some sharks (S. acanthias, Daliatias licha, and Scyliorhinus torazame) and ratfish (H. novaezealandiae, H. barbouri, and Rhinochimaera pacifica) (Hayashi and Takagi, 1982).…”