Lipid class and fatty acid composition of Calanus finmarchicus (Gunnerus), Pseudocalanus sp. and Temora longicornis Muller from a nutrient-enriched seawater enclosure

Abstract

Adult and late copepodite stages of Calanus finmarchicus (Gunnerus), Pseudocalanus sp. and Temora longicornis Muller sampled from a nutrient-enriched seawater enclosure containing a natural phytoplankton population were all rich in neutral lipid. Pseudocalanus sp. and C. finmarchicus contained mainly wax esters (WE) whereas T. longicornis contained mainly triacylglycerols (TAG). The WE of C. finmarchicus were characteristically rich in 16:0,20:1(n-9) and 22:1(n-11) fatty alcohols and 28% of the WE fatty acids were (n-3) polyunsaturated fatty acids (PUFA). Low levels of TAG in C. finmarchicus contained 28% of their fatty acids as (n-3) PUFA. The fatty alcohols of WE in Pseudocalanus sp. were primarily 16:0 and 14:0, with traces of 20:1(n-9) and 22:1(n-11). Of the WE fatty acids, 37% were (n-3) PUFA which was similar to the percentage of (n-3) PUFA in the TAG of this species. Triacylglycerols of T. longicornis contained 48 % of their fatty acids as (n-3) PUFA while the small amounts of WE in this species contained 45% (n-3) PUFA. The WE of T. longicornis contained primarily 16:0, 18:0, 20:1(n-9),22:1(n-11) and 24:0 fatty alcohols. The data are discussed with particular reference to the abundance and retention of (n-3) PUFA in marine food chains.