Objective: To evaluate the protective efficacy of certain chemoprotectants against cyclic peptide hepatotoxic microcystin-LR in mice. Material and Methods: Swiss albino female mice were used in all experiments for screening antidotes against the lethal dose of microcystin-LR (100 μg/kg body weight, i.p.). The agents, Dglucose, mannitol, dihydroxyacetone, Trolox, L-cysteine, N-acetylcysteine, am...

Toxic blooms of cyanobacteria are ubiquitous in both freshwater and brackish water sources throughout the world. One class of cyanobacterial toxins, called microcystins, is cyclic peptides. In addition to ingestion and dermal, inhalation is a likely route of human exposure. A significant increase in reporting of minor symptoms, particularly respiratory symptoms was associated with exposure to h...

The occurrence of toxic cyanobacterial blooms in aquatic environments, associated with human health problems and animal deaths, has increased the need for rapid, reliable and sensitive methods to determine the toxicity of microcystin produced by cyanobacteria. An in vitro Microtox(®) system and a commercially available microcystin ELISA were used to screen out the potential risk associated with...

Harmful, bloom-forming cyanobacteria (CyanoHABs) are occurring with increasing regularity in freshwater and marine ecosystems. The most commonly occurring cyanobacterial toxins are the hepatotoxic microcystin and nodularin. These cyclic hepta- and pentapeptides are synthesised nonribosomally by the gene products of the toxin gene clusters mcy and nda, respectively. Understanding of the regulati...

Both organic pollution and eutrophication are prominent environmental issues concerning water pollution in the world. It is important to reveal the effects of organic pollutants on algal growth and toxin production for assessing ecological risk of organic pollution. Since nonylphenol (NP) is a kind of persistent organic pollutant with endocrine disruptive effect which exists ubiquitously in env...

Due to the increasing oligotrophy of Lake Ammersee, southern Germany, metalimnic Planktothrix have become one of the dominant planktonic species causing regular blooms. Whitefish (Coregonus lavaretus) is the dominant local fish species with great importance for the fishing industry. Recently, whole age groups of this fish species have disappeared and since 1991, average body-weight has decrease...

Cyanobacteria, such as the toxin producer Microcystis aeruginosa, are predicted to be favored by global warming both directly, through elevated water temperatures, and indirectly, through factors such as prolonged stratification of waterbodies. M. aeruginosa is able to produce the hepatotoxin microcystin, which causes great concern in freshwater management worldwide. However, little is known ab...

The final purpose of our series of studies is to establish a biological removal method of cyanobacteria and their toxic products using immobilized microorganisms that can lyse cyanobacteria and decompose microcystins. To establish the biological removal method in non-point areas and water purification plants, as the first step, we explored bacteria active against the cyanobacterial hepatotoxin ...

Microcystin is a potent inhibitor of eukaryotic protein phosphatases and has been implicated in causing hepatotoxicity to humans and animals worldwide. It is produced primarily by the bloom-forming cyanobacterium Microcystis aeruginosa, although the function of the peptide in this micro-organism is unknown. In this study, a microcystin-related protein, MrpA, was identified using a microcystin-l...

AIMS The aims of present study were to evaluate the abundances, genetic diversity of total and microcystin-producing Microcystis over temporal and spatial scales, and to investigate relationships among Microcystis and water parameters in Tai and Yang-cheng lakes. METHODS AND RESULTS Abundances of total and microcystin-producing Microcystis varied across sampling periods and locations, which w...