1Department of Biological Production and Environmental Science, Faculty of Agriculture, Miyazaki University, Miyazaki, Miyazaki 889-2192, 2Graduate School of Food Science and Technology, Minami-Kyushu University, Takanabe, Miyazaki 884-0003, 3Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Fukuoka 812-8581, 4Nagase ChemteX Corporation, Fukuchiyama Factory 1, Fukuchiyama, Kyoto 620-0853, 5Graduate School of Agriculture, Kyoto University, Kyoto, Kyoto 606-8502, Japan
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.