South African fish products. Part XXIV.—The occurrence of α‐glyceryl ethers in the un‐saponifiable fractions of natural fats

Abstract

Tho amounts of farmaldehyde generated in the oxidation with periodic acid of the unsaponifiable fractions of a wide variety of fats from marine and other sources have been determined,1 and the results recorded in terms of percentage α‐glyceryl ethers, calculated as selachyl alcohol. It is demonstrated in this way that α‐glyceryl ethers are of wide occurrence in the unsaponifiable fractions from marine fats of many different types. They have been found less frequently, and in smaller amounts in the unsaponifiable fractions of land animal and vegetable fats.

Lipids: Their Distribution and Metabolism

“…(Karnovsky et al, 1946;Thompson and Lee, 1965;Isay et al, 1976). High amounts of glyceryl ethers were found in the hepatopancreas of Octopus rugosus, O. dofleini, and Octopus sp.…”

Glyceryl-ether monooxygenase [EC 1.14.16.5]. A microsomal enzyme of ether lipid metabolism

“…Since high levels of glyceryl ethers are toxic to some cells, a property which has been used to advantage in developing anticancer drugs (see below), the monooxygenase plays an important role in regulating the levels of these ethers. In tissues in which the ether levels are low, as in human liver, 16 the monooxygenase levels are high. Some neoplastic tissues were found to have low levels of the monooxygenase resulting in high levels of 1-alkyl-2,3-diacylglycerols.…”

“…They have been found in intestinal fat, cavity fat and liver oil of rat, in the domestic hen (particularly in the egg yolk), 16,47 bone marrow and milk of cattle and man, 48 spleen of pigs, 49 erythrocytes, 50 and in atherosclerotic arteries of man, 51 to name a few tissues. Glyceryl ethers are present in neonatal calf but their concentrations decrease rapidly after birth.…”

“…These alcohols exist mainly as diacyl derivatives of long chain fatty acids. [15][16][17][18] The elucidation of the structures of these alcohols took several years by separate research groups which involved oxidation procedures and finally unequivocal syntheses. [19][20][21][22][23][24][25] The experimental difficulties were due to the low melting and waxy nature, and close similarities of the physical properties of these alcohols.…”

Ether-Linked Lipids in Molluscs

“…The first broad survey for alkyl glyceryl ethers in organisms was con ducted by Karnovsky et al (1946). They estimated the alkyl ether content of tissue glycerolipids by oxidizing the nonsaponifiable fraction with periodate and quantifying any formaldehyde produced.…”