Composition and metabolism of phospholipids in Octopus vulgaris and Sepia officinalis hatchlings

The objective of the present study was to characterise the fatty acid (FA) profiles of the major phospholipids, of Octopus vulgaris and Sepia officinalis hatchlings, namely phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylethanolamine (PE); and to evaluate the capability of both cephalopod species on dietary phospholipid remodelling. Thus, O. vulgaris and S. officinalis hatchlings were in vivo incubated with 0.3 μM of L-∝-1-palmitoyl-2-[1-14C]arachidonyl-PC or L-∝-1-palmitoyl-2-[1-14C]arachidonyl-PE. Octopus and cuttlefish hatchlings phospholipids showed a characteristic FA profiles with PC presenting high contents of 16:0 and 22:6n-3 (DHA); PS having high 18:0, DHA and 20:5n-3 (EPA); PI a high content of saturated FA; and PE showing high contents of DHA and EPA. Interestingly, the highest content of 20:4n-6 (ARA) was found in PE rather than PI. Irrespective of the phospholipid in which [1-14C]ARA was initially bound (either PC or PE), the esterification pattern of [1-14C]ARA in octopus lipids was similar to that found in their tissues with high esterification of this FA into PE. In contrast, in cuttlefish hatchlings [1-14C]ARA was mainly recovered in the same phospholipid that was provided. These results showed a characteristic FA profiles in the major phospholipids of the two species, as well as a contrasting capability to remodel dietary phospholipids, which may suggest a difference in phospholipase activities.