OCTADECAPENTAENOIC ACID IN A RAPHIDOPHYTE ALGA, HETEROSIGMA-AKASHIWO

Total fatty acids from Heterosigma akashiwo contained 4.8-8.9 wt% of o ctadecapentaenoic acid (18:5n-3) through the growth cycle. This polyun saturated fatty acid was preferentially located in monogalactosyldiacy lglycerols and digalactosyldiacylglycerols (20.1% and 10.2% of fatty a cids, respectively, at day 18) with 0.3% or less in sulphoquinovosylgl ycerol (SQDG) +phosphatidylglycerol (PG) and phosphatidylcholine. The SQDG+PG fraction contained six cis 16:1 isomers. These findings are di scussed in relation to algal taxonomy. (C) 1997 Elsevier Science Ltd.