Non-methylene-interrupted Fatty Acids with Δ5 Unsaturation in Sargassum Species

• Published in: Journal of Oleo Science Vol. 61; no. 6; pp. 311 - 319
• Main Authors: Gwang-Woo, Kim, Yutaka, Itabashi
• Format: Journal Article
• Language: Japanese
• Published: 公益社団法人 日本油化学会 2012; Japan Oil Chemists' Society
• Subjects: 5,9-eicosadienoic acid; brown algae; non-methylene-interrupted fatty acids; Sargassum species; Δ5 unsaturation
• ISSN: 1345-8957; 1347-3352
• DOI: 10.5650/jos.61.311

Detailed fatty acid compositions of five species of the brown algae Sargassum (S. fulvellum, S. horneri, S. boreale, S. thunbergii, and S. yezoense) were determined using silver ion solid phase extraction, gas chromatography (GC), and GC-mass spectrometry (GC-MS) techniques. In addition to a high number of typical saturated and unsaturated fatty acids, the GC-MS spectra of the 4,4-dimethyloxazoline derivatives of fatty acids revealed the occurrence of small amounts of unusual non-methylene-interrupted (NMI) fatty acids with Δ5 unsaturation, namely, 5,9-eicosadienoic (5,9-20:2), 5,11,14-eicosatrienoic (5,11,14-20:3), and 5,11,14,17-eicosatetraenoic (5,11,14,17-20:4) acids. Of these three NMI acids, the 5,9-20:2 acid was found to be the most abundant (0.4%–2.3% of the total fatty acids) and was detected for the first time in algae.