Toxic compounds to Artemia from blooms and isolates of the cyanobacterium Planktothrix rubescens

Toxicity of Planktothrix (= Oscillatoria) rubescens from laboratory strains and natural blooms (from Lakes Leman and Nantua) was determined using the Brine Shrimp (Artemia salina) test and the microcystin content was analyzed by HPLC. Strains and blooms were toxic but the fractionation of the cell crude extract by solid-phase extraction revealed a toxicity for the Nantua and Paladru strains not related to microcystins, whereas for blooms and other strains the main toxins are forms of microcystin-RR.