Successful cultivation of the toxic dinoflagellate Dinophysis tripos (Dinophyceae)

Abstract

Since Park et al. (2006) succeeded in cultivating the toxic dinoflagellate Dinophysis acuminata and maintaining them by feeding them the ciliate Myrionecta rubra grown with a cryptophyte Teleaulax sp., the present study is the fifth report of propagation of a Dinophysis species (Dinophysis tripos) under laboratory conditions and describes the maintenance of clonal strains kept at relatively high abundance (>2,000 cells mL-1) for a relatively long period (>6 months) when fed on M. rubra with the addition of Teleaulax amphioxeia. Dinophysis tripos grew at a growth rate of 0.54 divisions day-1, reaching a maximum concentration of ca. 2,200 cells mL-1 during the first 14-day growth experiment. At the end of the incubations, the total amounts of pectenotoxin-2 and dinophysistoxin-1 in the D. tripos culture reached up to 2,780±216 (mean±SD) and 1.8±3.2 ng mL-1, respectively, therefore, we confirmed active toxin production. However okadaic acid (OA) was not detected from this culture before or after the incubation. These data clearly indicate that D. tripos needs to feed on their ciliate prey to actively produce the toxins.