Cryopreservation of marine thraustochytrids (Labyrinthulomycetes)

In this research, the viability of three marine thraustochytrid isolates (fungoid protists) (WSG05, W15 and WH3) were investigated after freezing in liquid nitrogen. Five cryopreservative combinations containing horse serum, glycerol and dimethylsulfide (Me(2)SO) were used. The thraustochytrids were assessed directly after removal from liquid nitrogen and cell concentration measured for 10 days postthawing. Results indicated that a combination of horse serum and Me(2)SO were the most effective cryoprotectants for each of the strains tested. Glycerol was only successful in producing growth in one of the strains once thawed. The protocols developed and tested in this study may have further application for cryopreserving other isolates in this class. (C) 2009 Elsevier Inc. All rights reserved.