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1
Content available remote Anabaena poulseniana J. Boye Petersen : a species new to Polish flora
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tom Vol. 42, No. 3
243--250
EN
Anabaena poulseniana J. Boye Petersen Bot. Iceland 2, 1923 (Cyanobacteria), a cyanobacteria species new to Polish flora, was noted during a study of phytoplankton in one of Wrocław’s clay pits. The species was noted in plankton samples among Cylindrospermopsis raciborskii (Wołoszyńska) Seenayya et Subba Raju (Cyanobacteria) and Mougeotia sp. (Chlorophyta) filaments. The green algae created a bloom characterized by vegetation mats floating on the water. The paper presents detailed characteristics for Anabaena poulseniana, and for the habitat and the ecological condition in the examined water reservoir during its presence. The paper also presents a comparison of morphological characteristics of A. poulseniana from Poland to the species from other geographical locations. The research will provide data on the morphology and ecology of the species. The species found during the study were documented in the form of original photos and illustrations.
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As a part of the study on the composition and development of microbial mats, it was attempted to develop new more effec-tive methods for the isolation and purification of cyanobacteria. The difficulty often encountered in the isolation and obtaining of axenic cultures is commonly known and well reflected by the great variety of purification methods used. Although numerous techniques have been described, most of them either failed or were not suitable for certain types of cultures. Differential gel electrophoresis and Percoll gradient centrifugation, applied by us, appear to be more effective than some other methods in reducing the number of heterotrophic bacterial 'contaminants' present in freshly isolated cultures of cyanobacteria from marine environment.
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This report presents results of the studies conducted in 2002 of eukaryotic algae and cyanobacteria found in the River Dunajec in the area of the newly built dam reservoirs in Czorsztyn and Sromowce. The studies demonstrated that diatoms were the dominant group in both the river (at 74 %) and the dam reservoirs (at 32 %), and that among the diatoms collected, eutraphenthic [van Dam et al. 1994] species usually prevailed. The diatom group, characterized by a broad ecological scale (tolerant), predominated slightly only at Station 3 located downstream from the dam reservoirs. This variation, which was probably connected with improved water quality in this part of the river, was the result of the sedimentation of pollutants in the dam reservoirs. Equally unexpected was the mass development of Didymosphenia geminata in this area. It occupied not only spots in the riverbed of the River Dunajec, but it also spread to the riversides and even to the river arms close to the confluence of the streams flowing from the Pieniny Mountains. The quantitatively dominant species in this area was Cladophora glomerata, which is an excellent habitat for other algae, particularly diatoms. The ultrastructure of its cell and cell wall is of great significance since it reflects the environmental conditions in which it lives. The ultrastructure of the Cladophora glomerata that occurred at different stations did not differ significantly, nor did it indicate the existence of any considerable hazard resulting from environmental pollution.
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Content available remote Influence of salinity on the growth of Nodularla spumigena mertens
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EN
The plankton material was sampled in August 1997 from the Gulf of Gdansk. The Cyanobacterium Nodularia spumigena strain (NSG 0897) was isolated from the samples. The effect of salinity on the growth of Nodularia spumigena was studied in the laboratory. Salinity had a significant effect on the number of cells, optical density, concentration of chlorophyll a, dry mass and growth rate. The Nodularia spumigena strain grew well in salinities 4-16 PSU. A salinity of 8 PSU is the best for the growth of this strain.
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Content available remote Mechanism and Effects of Cyanobacterial Hepatotoxin Action on Human Organism
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tom 124
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nr 3
156-159
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Eutrophication of waters and climate warming have created in the last decades favourable conditions for cyanobacteria colonization. The presence of cyanobacteria toxins in heavily polluted lake waters and fish ponds has become a current problem. These toxins belong to cyanobacteria secondary metabolites and are active in various fields of harmfulness to animals and humans. This group includes neurotoxins, dermatotoxins and hepatotoxins having a destructive influence on liver's cells. The group of hepatotoxins comprises microcystins and nodularin. The symptoms of hepatotoxin poisoning include stomach, intestine and liver disorders, intra-liver bleeding and physiological insufficiency of this organ. These compounds can induce apoptosis of liver cells and tumor promoters. From the above facts, it follows that hepatotox-ins can pose a very serious health problem on a global scale. This work presents the characteristic of cyanobacterial hepato-toxins, their chemical structure, properties, and mechanism of their action on human organism. The harmful influence caused by consuming products used in diet supplements, which contain microcystins was also pointed out.
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Content available remote Characterization of phycotoxins produced by cyanobacteria
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EN
Cyanobacteria (blue-green algae), photosynthetic prokaryotes, are essential elements of aquatic ecosystems. They produce a great variety of secondary metabolites; some of which have potentially useful pharmaceutical properties as anti-tumour, antibacterial and antiviral agents. Some species of cyanobacteria form blooms and become dominant over other forms of aquatic life. Blooms can deteriorate water quality in a variety of ways. Blooms formed by toxic species are the most harmful, as they can cause poisoning and death of organisms that come into contact with them. In this review, the structure and activity of cyanobacterial toxins are described. The toxins are classified into: hepatotoxins, neurotoxins, dermatotoxins and endotoxic lipopolysaccharides. Hepatotoxic cyclic pentapeptides, microcystins and nodularins, are the most common cyanobacterial toxins that have been identified in strains of Microcystis, Anabaena, Nodularia, Planktothrix (Oscillatoria), Nostoc, Hapalosiphon and Anabaenopsis. Cylindrospermopsin, another cyanobacterial hepatotoxin, is produced mainly by Cylindrospermopsis raciborskii. There are several neurotoxins produced by the cyanobacterial genera Anabaena, Aphanizomenon, Planktothrix and Cylindrospermopsis. Based on their activity, these neurotoxins were classified into anatoxin-a, anatoxin-a(S) and saxitoxins. BMAA is a novel cyanobacterial neurotoxin implicated in the ALS/PDC syndrome in the Chamorro people of Guam. The occurrence and harmful effects of cyanobacterial dermatotoxins and endotoxic lipopolysaccharides are less well recognised.
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Content available remote The potential causes of cyanobacterial blooms in Baltic Sea estuaries
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Nodularia spumigena Mertens, Aphanizomenon flos-aquae (L.) Ralfs and some species of the genus Anabaena are the dominant cyanobacterial taxa occurring in the Gulf of Gdańsk. The heterocystous cyanobacteria use dissolved molecular N2 as an additional nitrogen source, and this allows them to bloom during the summer when growth of other phytoplankton species is normally nitrogen-limited. Although cyanobacterial blooms have been reported in the Baltic Sea since the mid-19th century, the extent and intensity of blooms have recently increased due to anthropogenic sources of eutrophication. Increased river phosphorus input and changes in the phosphorus to nitrogen ratio are implicated as causal factors. After us the initial cause of the cyanobacterial bloom is a low N:P ratio, which indicates phosphorus excess, i.e. favourable nutrient conditions for nitrogen-fixing algae. An N:P ratio of 10 has been considered an approximate value for the N:P requirements of Baltic phytoplankton. For several years this ratio has been lower than 10. The mean annual value of the N:P ratio for the water of the Gulf of Gdańsk ranged from 3 to 7. Differences in the intensity of blooms observed in different years could be linked to temperature. During hot summers, when the seawater temperature increased to 20°C, large blooms were noted. For the cyanobacterial blooms in the Baltic Sea, the low N:P ratio is the primary factor and high temperature is a starting point.
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EPR spectroscopy using 5-doxylstearic acid (5-SASL) and 16-doxylstearic acid (16-SASL) spin probes was used to study the fluidity of thylakoid membranes. These were isolated from wild type Synechocystis and from several mutants in genes encoding selected enzymes of the carotenoid biosynthesis pathway and/or acyl-lipid desaturases. Cyanobacteria were cultivated at 25°C and 35°C under different light regimes: photoautotrophically (PAG) and/or in light-activated heterotrophic conditions (LAHG). The relative fluidity of membranes was estimated from EPR spectra based on the empirical outermost splitting parameter in a temperature range from 15°C to 40°C. Our findings demonstrate that in native thylakoid membranes the elimination of xanthophylls decreased fluidity in the inner membrane region under optimal growth conditions (25°C) and increased it under sublethal heat stress (35°C). This indicated that the overall fluidity of native photosynthetic membranes in cyanobacteria may be influenced by the ratio of polar to non-polar carotenoid pools under different environmental conditions.
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Microorganisms modify their biochemical composition in response to environmental factors, including nutrient availability, light, temperature and salinity. This research was carried out in order to establish ways of modifying the biochemical composition of marine cyanobacteria through the optimization of environmental parameters e.g. light, temperature and salinity. The effect of salinity stress in combination with variable temperature and light intensity was studied on Synechocystis sp., strain Ol 86, isolated from the North Sea. In nature, all microorganisms are exposed to different factors. Hence, we considered all the essential factors together in different groupings. Experiments were conducted at three different temperatures, two different light intensities and four different salinities. The influence of these factors on the growth and physiology of cyanobacteria from a microbial mat of the North Sea is reported.
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A two-year study on cyanobacterial development and the dynamics of intracellular microcystins was carried out in a shallow dam reservoir. Potentially toxic cyanobacteria (Microcystis wesenbergii, M. aeruginosa, Woronichinia naegeliana, Anabaena spp., Planktothrix agardhii) were observed to be the main component (70-94% total biomass) of the phytoplankton community, in which species composition was unstable and was very different between the 2005 and 2006 summer seasons. Generally, total phytoplankton, cyanobacterial biomass and total microcystin (MC) concentrations in the reservoir were much higher in 2006 than in 2005. The highest MC concentration (173.8 žg MC-LR equivalent dm-3) was seen in 2006 during P. agardhii (Oscillatoriales) domination (max. fresh biomass 50.3 mg dm-3; above 91% of phytoplankton biomass). Positive correlations between microcystin concentrations and cyanobacterial biomass suggest that populations of Nostocales and Oscillatoriales in 2005 and Oscillatoriales (P. agardhii) in 2006 may have been the main producers of MCs in the reservoir. The strong increase in P. agardhii biomass concomitant with a decrease in the total biomass of Chroococcales and Nostocales was responsible for the increase in MC concentration in the Siemianówka dam reservoir.
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During a monitoring programme the diet composition of Asplanchna priodonta was studied. Samples were collected every month from the deepest part of the Dobczycki dam reservoir (Southern Poland). The diet of A. priodonta, which included colonial cyanobacteria, diatoms, dinoflagelates and protozoa, indicated that it is both a grazer and a predator. These results support the hypothesis that A. priodonta is an opportunistic feeder. Additionally these results include the first observations of the protozoan Tintinnopsis sp. as a food source of Asplanchna.
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We report the first observation of large red cyanobacterial mats in the southern Baltic Sea. The mats (up to 2.5 m in diameter) were observed by SCUBA divers at 7.7 m depth on loamy sediments in the Gulf of Gdańsk in mid-November 2013. The main structure of the mat was formed by cyanobacteria Spirulina subsalsa Oersted ex Gomont; a number of other cyanobacteria, diatoms and nematode species were also present. After a few days in the laboratory, the red trichomes of S. subsalsa started to turn blue-green in colour, suggesting the strong chromatic acclimation abilities of this species.
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With the aid of epifluorescence microscopy, picoplankton (0.2-2mum) in the coastal zone of the Gulf of Gdansk (southern Baltic) was studied from March to December 1997. The main portion of the picoplankton biovolume was comprised of bacteria, making up on average 70% of picoplankton. Autotrophic picoplankton (APP) prevailed over the bacterioplankton only in late August and early September. The main components of APP were cyanobacteria. The APP proportion in the total phytoplankton biomass was highest in summer. The assessment of this share in terms of quantity varied depending on the picoplankton separation method. In the microscopic analysis of unfiltered samples, all cells 2mum were counted as picoplankton, including colony-forming types. Based on the analysis of unfiltered samples, the amount of APP in the overall phytoplankton biomass was assessed at 16-22% in summer, and 0.5-6% in the remaining period. Initial filtration of samples through a 2mum filter caused great losses in APP, resulting mainly in the elimination of colony-forming cyanobacteria cells from samples. Prefiltered samples were also contaminated by cells 2mum. In prefiltered samples the APP proportion in the total phytoplankton biomass was 1-7% in summer and 0.2-3% in the remaining period.
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tom Vol. 32, No. 1
27-38
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The structure, dynamics and chlorophyll a content of lithoreophilous communities of Cyanobacteria and algae in two periodically drying sectors of the stream: in its upper (alpine), and middle part (forest) zones were investigated. In both sectors the diversity of species was low. After snow melt, in the upper part, the stones were successively colonized by Cyanobacteria (with Chamaesiphon polonicus (Rostafiński) Hansgirg prevailing), and green alga Klebsormidium rivulare (Kütz.) Starmach, finally obtaining stable and abundant communities. In the middle part of the stream, a spring explosion of Klebsormidium rivulare and species from the Chlorococcales group was observed. They developed temporary, since they disappeared after the June spate. Later this area was colonised mainly by Homoeothrix janthina (Bornet et Flahault) Starmach, Hydrurus foetidus (Villars) Trevisan, and diatoms, coming from a neighbouring non drying part of the stream. The chlorophyll a content in both sectors was low (2 - 55.8 mg m –2) .
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Phosphatized biomorphs, resembling modern and ancient bacteria, were identified for the first time in phosphate nodules, present at the base of the Bílá Hora Formation (uppermost Cenomanian - lower Turonian), and in phosphate coprolites at the base of the Teplice Formation (upper Turonian) in the Bohemian Cretaceous Basin. They are present in colonies as filaments, coccoids, strings, rods and outgrowths, associated with the phosphate as part of the rock constituents and display the characteristics of fossilized bacteria. Two types of bacteria were identified: chemotrophic, sulphur-reducing bacteria in the phosphate nodules and phototrophic cyanobacteria in the phosphate coprolites. Microanalysis of some of the fossil bacteria revealed a fluoride-rich calcium phosphate composition, compatible with the composition of bulk samples, in which carbonate-fluorapatite is the main mineral in the phosphate nodules and coprolites. The environmental indications of these fossil bacteria support the interpretation of an anoxic environment of phosphogenesis in the latest Cenomanian - earliest Turonian and variable redox conditions of coprolite phosphatization in the late Turonian. The potential microbial role in phosphogenesis in the former may have involved the suboxic breakdown of P-rich organic matter by sulphur-reducing bacteria and the release of phosphorus in the pore water, leading to the biochemical precipitation of phosphate. The latter involved initial P-storage by phototrophic bacteria in an oxic environment, followed by P-release below the sediment-water interface under suboxic conditions and subsequent phosphatization of the coprolites.
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A mathematical model of the mechanism of the appearance of antisymmetric vortices during the propagation of freshwater into the seawater which is observed, in particular, at the exit from the Baltic Canal connecting the Vistula Lagoon and the Baltic Sea is constructed in the work. In particular it is shown that the main reason for the vortex formation in this case is the Coriolis force. The exact dependence of the circulation of velocity on time for the three simplest types of the “tongue” of the intrusion of freshwater is calculated analytically in the work as well.
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During the twenty-five years of existence, water quality has declined and severe blooms of cyanobacteria have occurred in the Grlište Reservoir. Changes in phytoplankton functional groups over time and along horizontal and vertical gradients were investigated in the course of a one-year study in this water-supply reservoir. We identified 19 dominant taxa, classified into 12 phytoplankton associations. The presence of the codons C, P, D and S1 differentiated the transitional from the lacustrine part of the reservoir. The nitrogen-fixing cyanobacteria Dolichospermum viguieri dominated the phytoplankton community in the epilimnion during August and September, when the reservoir showed P-limitation, but the bloom was not observed. The driving factors that accounted for the main variability in phytoplankton functional groups along the seasonal and vertical profile were identified using the direct gradient analysis (RDA). Our results revealed the importance of two bipolar factors. The first factor explained the variability in phytoplankton due to thermal stratification and physical mixing, each process affecting the algal community in contrasting ways. The second factor was interpreted as reduction vs. oxidation processes. Positive correlation between stratification and water pumping by a drinking water plant indicated that human activities were not severe enough to break down the thermal stability of the reservoir and to cause a cyanobacterial bloom.
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Cylindrospermopsin (CYN) is a cytotoxin produced by several species of cyanobacteria, which occur all over the world. It was demonstrated that CYN has a wide spectrum of biological activity in animal cells, involving hepatotoxicity, genotoxicity, cytotoxicity and carcinogenic potential, and is considered as one of the factors that caused human poisoning in Palm Island (Australia) and in Caruaru (Brazil). This compound may be introduced into organism by several ways, including consumption of water, fishes and seafood as well as accidental swallowing or aerosol spray inhalation during recreational using of reservoirs covered by cyanobacterial blooms. The information about the CYN impact on environment and its degradation processes under natural conditions is scant. Taking this into consideration CYN should be regarded as a potential threat to human health and life. This review presents physicochemical characteristic and biological activity of CYN, occurrence in freshwaters and its sensitivity to the influence of some environmental factors.
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Związki bioaktywne sinic wykazują różnorodne właściwości, które potencjalnie mogą być wykorzystane w wielu sektorach przemysłu. W artykule tym szczególny nacisk położono na wykorzystanie sinic i ich cyjanometabolitów, zarówno w przemyśle farmaceutycznym, jak i medycznym. Scharakteryzowano związki wyizolowane ze szczepów sinic, które można stosować do wytwarzania leków o działaniu przeciwwirusowym, przeciwgrzybiczym, przeciwnowotworowym, przeciwdrobnoustrojowym oraz przeciwbakteryjnym. Pokazano również pozytywne aspekty hodowli sinic i możliwości ich komercyjnego wykorzystania.
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The aim of this paper was a taxonomic verification of cyanobacteria of the genus Anabaena that occur in the Gulf of Gdańsk. Classical taxonomic methods were combined with modern molecular taxonomic methods (polyphasic approach). Analysis of the species diversity of cyanobacteria from the genus Anabaena was based on the microscopic analysis and on the analysis of 16S rRNA and ITS region. Comparison of the obtained results with sequences in GenBank showed 97.8-100% similarity for 16S rRNA and 98.8-100% similarity in the case of the ITS fragment. Similarity of the 16S rRNA and ITS sequence of 98.5% seems to be sufficient to determine the species.
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