Salinity tolerance and desalination properties of a strain from eastern Hungary.

Nowadays the increasing amount of saline wastewaters has given rise to various biological desalination processes, among which the application possibilities of microalgae represents a priority research area. Next to "real" aquatic species (members of phytoplankton or phytobenthon), species from ephemeral aquatic habitats or aeroterrestrial algae also could be good candidates of research studying salt tolerance or desalination ability, since salinity stress is often referred as "physiological drought" and species from ephemeral habitats can be characterized by high drought tolerance. In this study, the salinity tolerance, salt and nutrient removal ability of a strain from eastern Hungary were investigated.

Horseradish Essential Oil as a Promising Anti-Algal Product for Prevention of Phytoplankton Proliferation and Biofouling.

Increased proliferation of algae is a current problem in natural and artificial water bodies. Controlling nutrients is the most sustainable treatment of increased algal proliferation, however in certain cases, it is not sufficiently available, or it does not provide results fast enough. Chemicals derived from natural sources, which could be effective in low concentrations and are biodegradable, may have an advantage over conventional chemical treatments.

Trait convergence and trait divergence in lake phytoplankton reflect community assembly rules.

Environmental filtering and limiting similarity are those locally acting processes that influence community structure. These mechanisms acting on the traits of species result in trait convergence or divergence within the communities. The role of these processes might change along environmental gradients, and it has been conceptualised in the stress-dominance hypothesis, which predicts that the relative importance of environmental filtering increases and competition decreases with increasing environmental stress.

Environmental filtering and limiting similarity as main forces driving diatom community structure in Mediterranean and continental temporary and perennial streams.

Climatic extreme events such as droughts (unpredictable), dry periods (predictable) or even flush floods, threaten freshwater ecosystems worldwide. The filtering mechanisms of these events and their strength on communities, however, can be different among regions. While time-for-adaptation theory defines whether or not water scarcity can be considered as disturbance, the stress-dominance theory predicts an increase in importance of environmental filtering and a decrease in the role of biotic interactions in communities with increasing environmental stress.

Effects of non-steroidal anti-inflammatory drugs on cyanobacteria and algae in laboratory strains and in natural algal assemblages.

In recent years measurable concentrations of non-steroidal anti-inflammatory drugs (NSAIDs) have been shown in the aquatic environment as a result of increasing human consumption. Effects of five frequently used non-steroidal anti-inflammatory drugs (diclofenac, diflunisal, ibuprofen, mefenamic acid and piroxicam in 0.1 mg ml(-1) concentration) in batch cultures of cyanobacteria (Synechococcus elongatus, Microcystis aeruginosa, Cylindrospermopsis raciborskii), and eukaryotic algae (Desmodesmus communis, Haematococcus pluvialis, Cryptomonas ovata) were studied.

Effects of Cylindrospermopsin Producing Cyanobacterium and Its Crude Extracts on a Benthic Green Alga-Competition or Allelopathy?

Cylindrospermopsin (CYN) is a toxic secondary metabolite produced by filamentous cyanobacteria which could work as an allelopathic substance, although its ecological role in cyanobacterial-algal assemblages is mostly unclear. The competition between the CYN-producing cyanobacterium Chrysosporum (Aphanizomenon) ovalisporum, and the benthic green alga Chlorococcum sp. was investigated in mixed cultures, and the effects of CYN-containing cyanobacterial crude extract on Chlorococcum sp.

Alterations of phytoplankton assemblages treated with chlorinated hydrocarbons: effects of dominant species sensitivity and initial diversity.

Changes in composition of phytoplankton assemblages due to short-chained chlorinated hydrocarbons (tetrachloroethane, tetrachloroethylene and trichloroethylene) were studied in microcosm experiments with different initial diversities. Diversity decreased further during treatments in the less diverse 2011 summer assemblages, dominated by the euglenid Trachelomonas volvocinopsis (its relative abundance was nearly 70 %). Diversity did not change significantly during treatments in the more diverse 2012 summer assemblages, dominated by cryptomonads (their relative abundance was 40 %).

Zinc tolerance and zinc removal ability of living and dried biomass of Desmodesmus communis.

Effects of zinc on growth, cell morphology, oxidative stress, and zinc removal ability of the common phytoplankton species Desmodesmus communis were investigated at a concentration range of 0.25-160 mg L(-1) zinc. Cell densities and chlorophyll content decreased in treated cultures, changes in coenobia morphology and elevated lipid peroxidation levels appeared above 2.

Appearance of Planktothrix rubescens bloom with [D-Asp3, Mdha7]MC-RR in gravel pit pond of a shallow lake-dominated area.

Blooms of toxic cyanobacteria are well-known phenomena in many regions of the world. Microcystin (MC), the most frequent cyanobacterial toxin, is produced by entirely different cyanobacteria, including unicellular, multicellular filamentous, heterocytic, and non-heterocytic bloom-forming species. Planktothrix is one of the most important MC-producing genera in temperate lakes.

Observation of sward destruction caused by irrigation with toxic Microcystis morphospecies containing water in Southern Hungary.

In the summer of 2006 bloom-like phenomenon occurred in a garden pond in Szeged, Southern Hungary. After regular watering of a sward with pond water containing the algal mass, destruction of garden grass occurred. Microcystis aeruginosa, Microcystis viridis, Microcystis ichthyoblabe, and Microcystis wesenbergii were identified by light microscopy in the water sample; microcystin-FR, -LR, -RR and -YR were determined by matrix-assisted laser desorption/ionization--time-of-flight analysis.

Application of external micro-spectrophotometric detection to improve sensitivity on microchips.

The goal of this work was to increase the sensitivity of a UV-Vis spectrophotometer by decreasing the background noise and lengthening the optical path. A microphotometer has been modified to precisely select very small parts of a microfluidic channel pattern of a chip and to measure light absorbance on a magnified area of the selected part of the channel. The viability of combining a projection microscope and a spectrophotometer for external absorbance measurements on disposable PDMS chips was studied.

Cylindrospermopsin induces alterations of root histology and microtubule organization in common reed (Phragmites australis) plantlets cultured in vitro.

We aimed to study the histological and cytological alterations induced by cylindrospermopsin (CYN), a protein synthesis inhibitory cyanotoxin in roots of common reed (Phragmites australis). Reed is an ecologically important emergent aquatic macrophyte, a model for studying cyanotoxin effects. We analyzed the histology and cytology of reed roots originated from tissue cultures and treated with 0.

Microcystin-LR, a cyanobacterial toxin, induces growth inhibition and histological alterations in common reed (Phragmites australis) plants regenerated from embryogenic calli.

The aim of this study was to establish the histological effects of exposure to microcystin-LR (MC-LR), a cyanotoxin, on axenic Phragmites australis plantlets. Plantlets were regenerated from embryogenic reed calli by tissue culture methods. Microcystin-LR inhibited the growth and development of embryogenic calli and the growth of reed plantlets.

Alteration of cylindrospermopsin production in sulfate- or phosphate-starved cyanobacterium Aphanizomenon ovalisporum.

The effect of sulfate and phosphate deprivation on cell growth and cylindrospermopsin level was studied in Aphanizomenon ovalisporum ILC-164. Sulfate starvation induced a characteristic reduction of cylindrospermopsin pool size on the basis of cell number and unit of dry mass of culture. Phosphorous starvation of A.