Seven strains (NPCA-5, - 10, - 15, - 16, - 19, - 23, and - 29) of picoplanktonic cyanobacteria from Caruaru reservoirs were identified and analyzed for toxicity.
We tested the toxicity of these strains by mouse bioassay, by HPLC, and by enzyme-linked immunosorbent assay (ELISA).
Strains NPCA-15 and - 23 were toxic when tested by mouse bioassay (LD100=600 mgDW/kg body weight).
The toxin from strain NPCA-15 had the same UV spectrum as microcystin-LR.
All of the strains showed the presence of microcystin by ELISA analysis.
The microcystin concentration varied between 0.08 ng/mgDW (NPCA-5) and 3.7 ng/mgDW (NPCA-15).
Confirmation of microcystin production by picoplankton opens the possibility that these organisms may have contributed to human poisoning in Caruaru and defines a new source of microcystin in water supplies.
Mots-clés Pascal : Toxicité, Santé et environnement, Eau potable, Chromatographie HPLC, Cyanobacteria, Bactérie, Brésil, Amérique du Sud, Amérique, Milieu eau douce, Lac artificiel, Phytoplancton, Heptapeptide, Toxine, Microcystine
Mots-clés Pascal anglais : Toxicity, Health and environment, Drinking water, HPLC chromatography, Cyanobacteria, Bacteria, Brazil, South America, America, Freshwater environment, Artificial lake, Phytoplankton, Heptapeptide, Toxin
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 99-0327582
Code Inist : 002A05B10. Création : 16/11/1999.