Lipids of marine cold-water fishes

The study deals with the lipid and fatty acid compositions of the muscles, gills and liver of marine fishes inhabiting cold waters (0.5-6 degrees C) and caught in Peter the Great Bay (3 species) and Vostok Bay (2 species), as well as with the fatty acid compositions of the main phospholipids in the muscle tissues of fish from Olyutorskii Bay (4 species). The average content of phosphatidylcholine was about 60% in muscles and in the liver and 53.8% of the sum of all phospholipids in gills. The phosphatidylethanolamine content was on the average 24.3, 25.1 and 22.3% in muscles, liver and gills, respectively. Increased contents of phosphatidylserine and sphingomyeline were recorded in the gills. The mean (S.D.) molar ratios of cholesterol/phospholipids were 0.20, 0.32, and 0.58 in the muscles, liver, and gills, respectively. It was established that phosphatidylcholine has a higher content of saturated fatty acids, whereas phosphatidylethanolamine was richer in monoenic acids and docosahexaenoic acid (DHA). It was noted that the level of polyenic fatty acids was increasing and the level of monoenic and saturated acids was decreasing in the series from gills-liver-muscles. The species with a more active mode of life were distinguished by an increased content of docosahexaenoic acid.