TOXICITY TESTS IN 8 SPECIES OF CHRYSOCHROMULINA (HAPTOPHYTA)

Blooms of the marine flagellate Chrysochromulina have resulted in mort ality of marine organisms in Scandinavian waters, including fish in aq uaculture. Eight species of Chrysochromulina, namely C. apheles, C. br evifilum, C. ericina, C. hirta, C. leadbeateri, C. parva, C. polylepis , and C. simplex, isolated into unialgal culture, were examined for ha emolytic activity and toxicity to the brine shrimp, Artemia salina. Ha emolytic fractions were obtained from all species, but only C. polylep is cells were toxic to Artemia. Thin-layer chromatography (TLC) analys is in chloroform-methanol-water (75:25:4) and in chloroform-methanol ( 9:1) yielded up to six haemolytic spots. Except for one spot, these al l occurred in extracts of the species examined, including Isochrysis s p., which was used as a control, C. polylepis, and the well-known fish killer Prymnesium parvum. The single unique haemolytic spot (R-f valu es 0.45 and 0.16 in solvents I and II, respectively) occurred in the e xtract from C. polylepis. When isolated by TLC, the contents of the si ngle spot were toxic to Artemia.