Isolation of highly DHA-accumulated Labyrinthulales and their utilization for nutritional enrichment of rotifers and Artemia

Abstract

Twelve strains of highly DHA-accumulated Labyrinthulales were isolated from coastal sea water in Japan. The lipid contents in the cells and the DHA contents in the total fatty acids of these isolates were 13.7-23.0% and 21.5-55.4%, respectively. For the utilization of these isolates as a feed for nutritional enrichment of rotifers and Artemia, dispersibility of the cells in the water was evaluated. The cells of several isolates were agglutinated in sea water or tap water, and cawsed high mortality of rotifers and Artemia during their nutritional enrichment. Strain KY-1, however, showed high DHA content and good dispersibility in the water. Moreover, the DHA in KY-1 cells was rapidly transferred into rotifer and Artemia fed on KY-1 cells during their nutritional enrichment. These results showed that the strain KY-1 would be a novel and profitable feed for nutritional enrichment of rotifers and Artemia.