| Abstract
| - Seafood from Gilbert Bay, southern Labrador, was sampled for lipid classes, fatty acid, and sterolcomposition. Gilbert Bay is a proposed Marine Protected Area, and the composition of seafood fromthis region is interesting from both human health and ecological perspectives. Analyses includedfour species of bivalves and flesh and liver samples from four fish species. Lipids from a locallyisolated population of northern cod (Gadus morhua) were also compared to lipids from other codpopulations. Lipid classes were analyzed by Chromarod/Iatroscan TLC-FID, fatty acids by GC, andsterols by GC-MS. Three cod populations had similar levels of total lipid per wet weight (0.6%) withtriacylglycerols (TAG), sterols, and phospholipids comprising on average 13, 11, and 51%, respectively,of their total lipids. Fatty fish such as capelin and herring contained on average 8.4% lipid with 86%present as TAG. Fish livers from cod and herring showed opposite trends, with cod having elevatedlipid (27%) and TAG (63%) and herring containing only 3.8% lipid and 20% TAG. Shellfish averaged0.6% lipid; however, significant lipid class differences existed among species. Fatty acid analysisshowed few significant differences in cod populations with on average 57% polyunsaturated fattyacids (PUFA), 18% monounsaturated fatty acids (MUFA), and 24% saturated fatty acids (SFA). Codlivers had lower PUFA (34%) and elevated MUFA (44%) relative to flesh. Bivalves averaged 25%SFA, 18% MUFA, and 57% PUFA, whereas scallop adductor muscle had the highest PUFA levels(63%). Bivalves contained 20 different sterols with cholesterol present as the major sterol (19−39%).trans-22-Dehydrocholesterol, brassicasterol, 24-methylenecholesterol, and campesterol individuallyaccounted for >10% in at least one species. High levels of PUFA and non-cholesterol sterols observedin Gilbert Bay seafood demonstrate their positive attributes for human nutrition. Keywords: Cholesterol; docosahexaenoic acid; eicosahexaenoic acid; ω−3 fatty acids; phytosterols
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