FATTY CHAIN COMPOSITION OF ETHER AND ESTER GLYCEROPHOSPHOLIPIDS IN THE JAPANESE OYSTER CRASSOSTREA-GIGAS (THUNBERG)

The fatty chain compositions of 1-O-alk-1′-enyl-2-acyl, 1-0-alkyl-2-acyl, and 1,2-diacyl glycerophospholipids of the Japanese oyster Crassostrea gigas (Thunberg) were investigated. Major fatty chains in the sn-1 position of 1-alk-1′-enyl-2-acyl ethanolamine phospholipids (EPL) were 18:0 (64.7%) and 20:1 (11.1%). Major sn-1 chains of alkenylacyl choline phospholipids (CPL) were 18:0 (63.3%) and 16:0 (22.2%). In the case of 1-alkyl-2-acyl EPL, the predominant fatty chains in the sn-1 position were 18:0 (51.5%), 16:0 (16.0%) and 20:1 (12.5%); in the case of 1-alkyl-2-acyl CPL, the major sn-1 chains were 16:0 (44.0%) and 14:0 (23.4%). Saturated fatty chains were predominant in both EPL and CPL. Prominent fatty acids in the sn-2 position of the alkenylacyl EPL were 22:6n-3 (29.0%), 20:5n-3 (19.0%) and 22:2 NMID (non-methylene interrupted dienes, 16.6%) contributing to about 65% of the total fatty acids, while alkenylacyl CPL was rich in the saturated acids 16:0 (32.0%) and 18:0 (9.2%). In the alkylacyl EPL, 16:0, 18:1n-9, 18:0 and 16:1n-7 were prominent sn-2 fatty acids and accounted for 30.6%, 10.0%, 9.8%, and 8.3%, respectively. Polyunsaturated fatty acids were detected, but were present at extremely low percentages. Major sn-2 fatty acids in alkylacyl CPL were 16:0 (25.4%), 22:6n-3 (16.0%) and 20:5n-3 (8.4%). The major fatty acids of diacyl EPL were 20:5n-3 (22.3%), 16:0 (17.9%), and 18:0 (16.1%), and those of diacyl CPL were 16:0 (30.4%), 20:5n-3 (17.6%) and 18:1n-7 (7.4%). © 1990 American Oil Chemists' Society.