Seasonal changes in lipid, fatty acid, α-tocopherol and phytosterol contents of seaweed, Undaria pinnatifida, in the Marlborough Sounds, New Zealand

Abstract

Monthly changes of lipids, fatty acids, phytosterol and α-tocopherol in New Zealand brown macroalgae, Undaria pinnatifida, were investigated. U. pinnatifida lipid content ranged from 17 to 45mg/g in the blade and between 21 and 63mg/g in the sporophyll. It was a rich source of polyunsaturated fatty acids (PUFAs) with n-6 PUFAs reaching a maximum in December. The unsaponifiable lipid was comprised of α-tocopherol, fucosterol and 24-methylenecholesterol, that were found in higher concentrations in the winter. The content of fucosterol ranged from 146 to 338μg/g, and that of 24-methylenecholesterol between 8.4 and 48μg/g. The contents of α-tocopherol were 13, 14 and 9.6μg/g in winter, spring and summer, respectively. New Zealand U. pinnatifida sporophyll had a high level of beneficial lipids and could potentially be further processed as a source of functional food lipids instead of being discarded as a waste product.