Production and sedimentation of peptide toxins nodularin-R and microcystin-LR in the northern Baltic Sea.

This seven-year survey was primarily targeted to quantification of production of nodularin-R (NOD-R), a cyclic pentapeptide hepatotoxin, in Baltic Sea cyanobacteria waterblooms. Additionally, NOD-R and microcystin-LR (MC-LR; a cyclic heptapeptide toxin) sedimentation rates and NOD-R sediment storage were estimated. NOD-R production (70-2450 microg m(-3); approximately 1 kg km(-2) per season) and sedimentation rates (particles; 0.

Accumulation and effects of nodularin from a single and repeated oral doses of cyanobacterium Nodularia spumigena on flounder (Platichthys flesus L.).

Nodularin (NODLN) is a cyclic pentapeptide hepatotoxin produced by the cyanobacterium Nodularia spumigena, which occurs regularly in the Baltic Sea during the summer season. In this study flounder (Platichthys flesus L.) was orally exposed to NODLN either as a single dose or as three repeated doses 3 days apart.

Chromatographic characterization of substance P endopeptidase in the rat brain reveals affected enzyme activity following heat stress.

This paper describes a study of substance P endopeptidase (SPE)-like activity in various regions of the brain from male rats subjected to heat stress (HS). The enzyme activity was found to be affected in several brain areas including cerebellum, cerebral cortex, hippocampus, hypothalamus[sol ]thalamus and the spinal cord following HS. Significant increases in SPE activity were observed in, for example, hippocampus and the spinal cord.

Quantitative LC-ESI-MS analyses of microcystins and nodularin-R in animal tissue--matrix effects and method validation.

The matrix effects and signal response in LC-MS analysis of six microcystins and nodularin-R were studied in mussels and liver samples from the common eider and rainbow trout. The instrumentation used in the study was a triple quadrupole MS with electrospray ionization. The results from the spiked tissue samples showed that both signal suppression and enhancement occurred.

Oxidation of the cyanobacterial hepatotoxin microcystin-LR by chlorine dioxide: reaction kinetics, characterization, and toxicity of reaction products.

Cyanobacteria are known producers of cytotoxins, hepatotoxins, and neurotoxins. The main toxins are microcystins, cyclic heptapeptide hepatotoxins, produced by strains of several cyanobacterial genera frequently found in eutrophied freshwaters. Due to the acute and chronic toxicity of microcystins, successful removal of these toxins in drinking water treatment processes is of increasing concern.

Eiders (Somateria mollissima) obtain nodularin, a cyanobacterial hepatotoxin, in Baltic Sea food web.

Nodularin (NODLN) is a cyclic pentapeptide hepatotoxin produced by the cyanobacterium Nodularia spumigena, which occurs regularly in the Baltic Sea during the summer season. Nodularia blooms have caused several animal kills in the Baltic Sea area, and NODLN has been found in mussels and fish caught from the northern Baltic Sea in 1996 to 2002. We analyzed liver samples of common eider (Somateria mollissima) for NODLN by enzyme-linked immunosorbent assay (ELISA) and liquid chromatography/mass spectrometry (LC-MS).

Mass spectrometric detection and quantification of nodularin-R in flounder livers.

Livers of flounders caught during August 1995 from the western Gulf of Finland and the Archipelago Sea were analyzed for nodularin-R (NODLN) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and liquid chromatography-electrospray ionization-mass spectrometry (LC-MS). Results showed that NODLN was detected in samples by both MS techniques. NODLN content in samples varied between 0.

Mass spectrometric detection of nodularin and desmethylnodularin in mussels and flounders.

Samples of mussels and flounders from the Baltic Sea were analysed for nodularin content on two different LC-MS instruments (triple quadrupole and ion trap). The triple quadrupole instrument was well suited for the quantitative analysis. The limit of detection in the selected ion recording mode was 5 pg and in the multiple reactant monitoring mode 500 pg on column for extracts of Nodularia spumigena.