Seasonal Lipid Composition in Macroalgae of the Northeastern Pacific Ocean

Abstract

The lipid classes and fatty acid profiles of macrophytic algae from the Phaeophyta (Egregia menziesii), Rhodophyta (Chondracanthus canaliculatus) and Chlorophyta (Ulva lobata) were determined. Ulva lobata contained the highest amounts of lipids (20-29 mg g - 1 dry mass), followed by Egregia menziesii (9-16 mg) and Chondracanthus canaliculatus (2-3 mg), with increased lipids in winter and spring. This was reflected in total fatty acid content (14-24, 6-13 and 1-2 mg g - 1 dry mass, respectively). Major lipid classes were polar lipids (44-94 % of total lipids) and sterols (3-8 %). Higher levels of triacylglycerols occurred in Egregia menziesii during spring (22 %) and in Ulva lobata during summer (12 %). Free fatty acids were also variable (0-26 %). Triacylglycerols were not detected in Chondracanthus canaliculatus. Low levels of wax esters and diacylglyceryl ethers were detected in Ulva lobata (0.1 %). The major fatty acid common to all species was 16:0. Egregia menziesii and Chondracanthus canaliculatus contained 14:0, 18:1(n-9), 20:4(n-6) and 20:5(n-3) as major components. Egregia menziesii and Ulva lobata also contained 18:2(n-6), 18:3(n-3) and 18:4(n-3), and Chondracanthus canaliculatus and Ulva lobata contained 18:1(n-7). Large amounts of C 1 6 polyunsaturated fatty acids and the presence of 22:0 and C 2 2 polyunsaturated fatty acids were unique to U. lobata. Knowledge gained regarding macroalgal lipid composition may prove useful in raising mariculture species.