2017 Volume 33 Issue 1 Pages 19-29
To evaluate the occurrence of polyunsaturated fatty acids as phenotypic markers, we analyzed the fatty acid compositions of 235 strains of microalgae within the divisions Heterokontophyta, Cryptophyta, and Haptophyta held in the Microbial Culture Collection at the National Institute for Environmental Studies. Eicosapentaenoic acid (EPA, 20:5) was present at >10% of the total fatty acid composition in 119 strains. Docosahexaenoic acid (DHA, 22:6) DHA was present at >10% of the total in 16 strains, most in the Haptophyta, in addition to two unidentified strains in the Pelagophyceae (Heterokontophyta). Strains of the Heterokontophyta other than the Chrysophyceae and the Pelagophyceae and the strains of Cryptophyta typically contained more EPA than DHA. The Heterokontophyta, with 11 classes, including the newly recognized Aurearenophyceae, Pelagophyceae, and Schizocladiophyceae, showed diverse fatty acid profiles, although clear phenotypic results defining each taxonomic group were not confirmed.