Cyanobacterial Toxins Research Papers - Academia.edu (original) (raw)

- by and +1
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- Cyanobacteria, Cyanobacterial Toxins

The paper provides a brief generalization on algal toxins as risk factors for national security and defense with special attention to Bulgaria. With the changing environmental conditions, globalization and increased human migration the... more

- by Maya Stoyneva and +1
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- Cyanobacteria, Algae, Cyanobacterial Toxins, Cyanotoxins

Cyanobacteria, also known as blue-green algae, blue-green bacteria or cyanophyta, is a phylum of bacteria that obtain their energy through photosynthesis. They are a significant component of the marine nitrogen cycle and an important primary producer in many areas of the ocean, but are also found in habitats other than the marine environment; in particular, cyanobacteria are known to occur in both freshwater and hypersaline inland lakes. They are found in almost every conceivable environment, from oceans to fresh water to bare rock to soil. Cyanobacteria are the only group of organisms that are able to reduce nitrogen and carbon in aerobic conditions, a fact that may be responsible for their evolutionary and ecological success. Certain cyanobacteria also produce cyanotoxins. This new book presents a broad variety of international research on this important organism.

- by Maya Stoyneva
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- Cyanobacteria, Harmful algal blooms, Harmful Algal Blooms (Biology), Algology

Cyanobacteria are present in all aquatic ecosystems throughout the world. They are able to produce toxic secondary metabolites, and microcystins are those most frequently found. Research has displayed a negative influence of microcystins and closely related nodularin on fish, and various histopathological alterations have been observed in many organs of the exposed fish. The aim of this article is to summarize the present knowledge of the impact of microcystins and nodularin on the histology of fish. The observed negative effects of cyanotoxins indicate that cyanobacteria and their toxins are a relevant medical (due to irritation, acute poisoning, tumor promotion, and carcinogenesis), ecotoxicological, and economic problem that may affect both fish and fish consumers including humans.

- by Zorica Svircev and +1
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- Cyanobacteria, Multidisciplinary, FISH TOXICOLOGY, Cyanobacterial Toxins

Cyanobacteria are well known producers of a wide variety of allelochemicals, which positively or negatively affect sympatric organisms from similar or even different taxons. In the traditional approach for studying allelopathy in water systems, cyanobacteria and photoautotrophic micro-eukaryotes were grouped together under the term of micro-algae. Because these two groups are phylogenetically and phenotypically distinct and the production of allelopathic compounds is often highly species- and even strain-dependent, it is appealing to assess the present available knowledge concerning allelopathy within and among cyanobacteria separately.
In this chapter, information is reviewed about i) cyanobacterial production of alleopathic substances, ii) the chemical nature of these allelopathic secondary metabolites, and iii) the mechanisms of the allelopathic inhibition. Furthermore, (iv) the possibility to use allelopathy to control harmful cyanobacterial blooms is discussed.

- by Miro Svercel
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- Bacteriology, Cyanobacteria, Allelopathy, Cyanobacterial blooms

Cylindrospermopsin (CYN) is a cytotoxic alkaloid produced by cyanobacteria. The distribution of this toxin is expanding around the world and the number of cyanobacteria species producing this toxin is also increasing. CYN was detected for the first time in Turkey during the summer months of 2013. The responsible species were identified as Dolichospermum (Anabaena) mendotae and Chrysosporum (Aphanizomenon) ovalisporum. The D. mendotae increased in May, however, C. ovalisporum formed a prolonged bloom in August. CYN concentrations were measured by LC-MS/MS and ranged from 0.12 μg·mg−1 to 4.92 μg·mg−1 as dry weight, respectively. Both species were the only cyanobacteria actively growing and CYN production was attributed solely to these species. Despite CYN production by C. ovalisporum being a well-known phenomenon, to our knowledge, this is the first report of CYN found in D. mendotae bloom.

- by Reyhan Akçaalan
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- Cyanobacterial Toxins
- by Maya Stoyneva and +1
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- Cyanobacteria, Algology, Cyanobacterial blooms, Cyanobacterial Toxins

Cyanobacteria thrive in many aquatic environments, where they can produce cyanotoxins with different toxicological profiles. This report provides the guidelines for the management of cyanobacterial blooms in bathing water, put together by a group of experts. The first part summarizes the current scientific knowledge on various aspects, including their presence in the Italian lakes, chemical and toxicological characteristics of different cyanotoxins, the observed effects on human health and the risk assessment. The second part defines the guidelines to prevent harmful effects on the health of bathers and manage the risk associated with blooms. It provides recommendations for planning environmental monitoring activities and a health surveillance system in most critical areas. It also introduces an environmental and health reporting system, with the purpose to standardize the information at national level too. The report is supplemented by technical information aimed at territorial aut...

- by Nico Salmaso
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- Aquatic Ecology, Limnology, Phytoplankton Ecology, Aquatic Toxicology

Cyanobacterial blooms in fresh water bodies have a serious negative impact on human, animal and environmental health. The impact of electro-oxidation of water containing Planktothrix rubescens in electrolytic cell equipped with diamond electrodes has been tested. The treatment had an immediate effect on cyanobacterial phycocyanin and chlorophyll fluorescence response and total cell biovolume. Cyano-bacterial number reduced for 80 % 130 h after a single treatment of 500 mL of a water sample through electrolytic cell with a flow rate 1 L/min. Obtained results indicate a great potential of the method for in-lake cyanobacterial control. Izvleček: Pojav cianobakterijskega cveta v sladkih vodah negativno vpliva na zdravje ljudi, na živali in okolje. Z elektrolitsko celico, opremljeno z borom dopiranima diamantima elektrodama, smo povzročili elektrooksidacijo in testirali njen vpliv na Planktotrix rubescens. Tretiranje je imelo takojšen vpliv na fluorescenco klorofila, na fluorescenco cianobakterijskega fikocianina in na celotni biovolumen cianobakterijskih celic. Volumen vzorca je bil 500 ml, pretok skozi elektrolitsko celico pa je znašal 1l/ min. 130 ur po tretiranju se je število cianobakterijskih celic zmanjšalo za 80 %. Rezultati kažejo na velik potencial te metode pri nadzoru cianobakterijske populacije. Ključne besede: elektrolitska celica, z borom dopirana diamantna elektroda, cianobakterijski cvet, hidroksilni radikali

- by Maša Čater and +1
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- Microbiology, Water quality, Cyanobacterial Toxins

The present research work explores the important physico-chemical parameters of
waste water collected from different areas i.e. Domestic sewage area, Hospital sewage area and
Industrial sewage area of Sagar (M.P.), India. An intensive analytical program was followed by
January to December (2013) for monitoring waste water. Monthly changes in physical and chemical
parameters of water such as pH, Temperature, Total Dissolved Solids (TDS), Dissolved Oxygen
(DO), Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Hardness,
Chlorides, Alkalinity, Phosphate and Nitrate were recorded and their correlations were estimated.
The study reveals that dumping of waste materials in different drainage systems pollute aquatic and
surroundings of terrestrial environment thereby affecting the growth of vegetation and aquatic life.
The outcome of the present investigation points out that it requires to implement common
objectives, compatible policies and programs for improvement in the waste water treatment
methods. Waste should be properly disposed or recycled. Relevant agencies should make
continuous efforts to educate, regulate and control people for environmental changes and suggest
them to change their policies of waste water management.
Keywords:- BOD, COD, DO, TDS

The occurrence of n-saturated, branched, and unsaturated fatty acids of 3 wild terrestrial strains of the genus Chroococcidiopsis (Order Chroococcales): C. supralittoralis, C. umbratilis, and C. ver-satilis collected from Lake Kinneret, Dead Sea, and Ein Kerem (Jerusalem) was investigated and individual compounds identified by gas chromatography–mass spectrometry. Polar lipids also were examined. Among polar lipids (studied using two-dimensional thin-layer chromatography) were as major glycolipids isolated: monogalactosyl-diacylglycerols, digalactosyl-diacylglycerols, 6-sulfoquinovosyl-diacylglycerols and phos-phatidylglycerol. Nonphosphorus betaine-containing lipid, viz. N,N,N-trimethylhomoserin-4-O-yl-diacylgly-
cerol, was found for the first time in cyanobacterial species.

Toxic cyanobacterial blooms in urban lakes present serious health hazards to humans and animals and require effective management strategies. Managing such blooms requires a sufficient understanding of the controlling environmental factors. A range of them has been proposed in the literature as potential triggers for cyanobacterial biomass development and cyanotoxin (e.g. microcystin) production in freshwater systems. However, the environmental triggers of cyanobacteria and microcystin variability remain a subject of debate due to contrasting findings. This issue has raised the question of whether the relevance of environmental triggers may depend on site-specific combinations of environmental factors. In this study, we investigated the site-specificity of environmental triggers for cyanobacterial bloom and microcystin dynamics in three urban lakes in Western Australia. Our study suggests that cyanobacterial biomass, cyanobacterial dominance and cyanobacterial microcystin content variability were significantly correlated to phosphorus and iron concentrations. However, the correlations were different between lakes, thus suggesting a site specific effect of these environmental factors. The discrepancies in the correlations could be explained by differences in local nutrient concentration. For instance, we found no correlation between cyanobacterial fraction and total phosphorous (TP) in the lake with the highest TP concentration, while correlations were significant and negative in the other two lakes. In addition, our study indicates that the difference of the correlation between total iron (TFe) and the cyanobacterial fraction between lakes might have been a consequence of differences in the cyanobacterial community structure, specifically the presence or absence of nitrogen-fixing species. In conclusion, our study suggests that identification of significant environmental factors under site-specific conditions is an important
strategy to enhance successful outcomes in cyanobacterial
bloom control measures.

- by Elke S Reichwaldt
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- Cyanobacteria, Harmful algal blooms, Cyanobacterial Toxins, Microcystin

Zebra mussel invasion of northern American lakes during the last century may play an important role in the occurrence of toxic cyanobacteria blooms. Herein, large-scale data from the USEPA National Lake Assessment (> 1,000 lakes) were used to study the potential linkage between zebra mussels, cyanobacteria community composition, and cyanotoxin levels in the lakes. ANOVA Based on Dissimilarities tests (Adonis) showed that there was a significant difference in cyanobacterial communities between lakes located in areas with and without established zebra mussel populations. Meanwhile, significantly higher microcystin levels and cyanobacteria abundance were observed, but lower concentrations of phosphorous in lakes located in areas with established zebra mussels. Structural equation modeling was used to confirm and estimate the effect of zebra mussels on microcystin concentrations via different pathways. The results suggest three potential pathways whereby zebra mussels influence microcystin production: 1) altering phosphorous concentration; 2) increasing cyanobacteria abundance; and 3) shifting cyanobacteria community structure. The total effect of zebra mussel establishment resulted in an overall 1.40 times net increase in microcystin level, which presumably resulted from three contributing factors: 1) a 1.06 times increase through an increased cyanobacteria abundance; 2) a 1.53 times increase through a selective force, resulting in increased cyanobacteria toxicity; and 3) a 0.86 times decrease in microcystin level through total phosphorus decrease. The study suggested the important potential role of zebra mussel invasion in altering cyanobacterial composition and influencing microcystin levels in the US lakes.

- by Ozeas Costa
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- Toxicology, Aquatic Toxicology, Cyanobacteria, Great Lakes

Supplied water in semiarid region was analyzed concerning heavy metals, cyanobacteria and radiation. Indoor radon and gamma emitters (U, K and Th) concentrations were measured. High radon levels are present inside urban residences. It was found high frequencies of micronuclei and nuclear alterations in human oral mucosa. High background radioactivity could explain the observed mutagenic effect observed. a b s t r a c t Lucr ecia city, known to harbor a high cancer rate, is located in a semiarid region characterized by the presence of mineral reservoirs, facing a high exposure to metal and natural radioactivity. The present study aimed to assess the environmental scenario at a semiarid region located in Northeastern Brazil. Metal concentration, alpha and beta radiation, and cyanobacteria content in tap water along with indoor radon and gamma emitters (U, K and Th) concentrations were measured. In addition, mutagenic and nuclear instability effects were assessed using buccal micronucleus cytome assay. The study included five samplings corresponding to a period between 2007 and 2009. Drinking water from Lucr ecia city presented levels of Mn, Ni and Cr along with cyanobacteria in concentrations one to four times higher than regulatory guidelines considered. Furthermore, high levels of all the tested radionuclides were found. A high percentage of the houses included in this study presented indoor radon concentrations over 100 Bq m À3. The mean annual effective dose from Lucr ecia houses was six times higher than observed in a control region. The levels of exposure in most of the Lucr ecia houses were classified as middle to high. A significant mutagenic effect, represented as an increase of micronuclei (MN) frequency and nuclear abnormalities as nuclear buds (NB), binucleated cells (BN), and pyknotic cells (PYC) were found. The results obtained highlight the role of high background radioactivity on the observed mutagenic effect and could help to explain the exacerbated cancer rate reported in this locality.

- by Maya Stoyneva and +2
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- Cyanobacteria, Algae, Cyanobacterial Toxins, Blue Green Algae

- by Dario Andrinolo
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- Cyanobacteria, Argentina, Environmental Monitoring, Rivers

- by Elke S Reichwaldt and +1
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- Bioaccumulation, Cyanobacteria, Daphnia, Harmful algal blooms

""Microcystins are produced by several species of cyanobacteria and can harm aquatic organisms and human beings. Sediments have the potential to contribute to the removal of dissolved microcystins from the water body through either adsorption to sediment particles or biodegradation by the sediment’s bacterial community. However, the relative contribution of these two removal processes remains unclear and little is known about the significance of sediment’s overall contribution. To study this, changes in the concentration of microcystin-LR (MCLR) in the presence of sediment, sediment with microbial inhibitor, and non-sterile lake water were quantified in a laboratory experiment. Our results show that, in the presence of sediment, MCLR concentration decreased significantly in an exponential way without a lag phase, with an average degradation rate of 9 mg d-1 in the first 24 h. This indicates that sediment can contribute to the removal of MCLR from the water immediately and effectively. Whilst both, the biodegradation and adsorption ability of the sediment contributed significantly to the removal of MCLR from the water body, biodegradation was shown to be the dominant removal process. Also, the sediment’s ability to degrade MCLR from the water was shown to be faster than the biodegradation through the bacterial community in the water. The present study emphasizes the importance of sediments for the removal of microcystins from a water body. This will be especially relevant in shallow systems where the interaction between the water and the sediment is naturally high. Our results are also useful for the application of sediments to remove microcystins at water treatment facilities.""

- by Haihong Song and +2
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- Adsorption, Biodegradation, Cyanobacterial Toxins, Microcystin

Cyanobacteria are well known producers of a wide variety of allelochemicals, which positively or negatively affect sympatric organisms from similar or even different taxons. In the traditional approach for studying allelopathy in water systems, cyanobacteria and photoautotrophic micro-eukaryotes were grouped together under the term of micro-algae. Because these two groups are phylogenetically and phenotypically distinct and the production of allelopathic compounds is often highly species- and even strain-dependent, it is appealing to assess the present available knowledge concerning allelopathy within and among cyanobacteria separately. In this chapter, information is reviewed about i) cyanobacterial production of alleopathic substances, ii) the chemical nature of these allelopathic secondary metabolites, and iii) the mechanisms of the allelopathic inhibition. Furthermore, (iv) the possibility to use allelopathy to control harmful cyanobacterial blooms is discussed.

- by Miro Svercel
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- Bacteriology, Cyanobacteria, Allelopathy, Cyanobacterial blooms
- by Maya Stoyneva
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- Cyanobacteria, Lakes, Algology, Cyanobacterial blooms

Cyanobacteria constitute the main toxin producers in inland water ecosystems and have extensive global distribution. The presence of hepatotoxins in aquatic environments is hazardous to human and animal health; even though the presence and identification of hepatotoxic microcystins in rivers and reservoirs of the world have been confirmed by several studies in the last few years. Herein, we studied the abundance and toxicity of Microcystis aeruginosa in the Argentine section of the Paraná River at the beginning of the Middle Paraná (Corrientes Hydrometer), near Corrientes city (27o28 ́ S - 58o51 ́ W) and approximately 220 km downstream of the Yacyretá dam (High Paraná). The Paraná River basin, with a drainage area of 3.1 x 10 6 km 2 and 3 965 km in length, is the second largest catchment of South America, after that of the Amazon. The Paraná River is the main source of drinking water supply for the Northeastern Argentine region. Phytoplankton samples were collected and environmental variables were measured in a monthly basis (exceptionally fortnightly), from March 2004 to June 2008. Fifty-eight samples were analyzed for phytoplankton density and biomass. Five samples were used for toxicity testing; the latter were obtained during the cyanobacteria blooms from 2005 to 2008. Phytoplankton counts were performed with an inverted microscope, and biomass was expressed as biovolume. Bioassays with mice and high-performance liquid chromatography (HPLC) analysis were performed to evaluate the presence of cyanotoxins. Phytoplankton mainly consisted of Cryptophyta, Chlorophyta and Bacillariophyta. Microcystis aeruginosa was identified during the warmer months each year (November to March). Density varied between 189 and 25 027 cells/mL (1-10 colonies/mL) and biomass from 0.34 to 44 mm 3 /L. Taking into account the number of cells, the highest abundance occurred in April 2004 (25 027 cells/mL), coinciding with the largest biovolume (44 mm 3 /L). All mice subjected to intraperitoneal injections with samples obtained during bloom episodes showed positive results for the presence of hepatotoxins. Three microcystins variants: LR, RR and [D-Leu 1] Mcyst-LR were detected by analysis with semi-preparative high-performance liquid chromatography with diode array detector system (HPLC-PDA). This constitutes the first report of microcystins recorded dur- ing M. aeruginosa blooms in the Argentine stretch of the Paraná River at the beginning of the Middle Paraná (Corrientes Hydrometer), approximately 220 km downstream of the Yacyretá dam (High Paraná). Rev. Biol. Trop. 64 (1): 203-211. Epub 2016 March 01.

- by Biología Tropical
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- Cyanobacteria, Cyanobacterial Toxins, Microcystins, Hepatotoxins

Alert level frameworks advise agencies on a sequence of monitoring and management actions, and are implemented so as to reduce the risk of the public coming into contact with hazardous substances. Their effectiveness relies on the detection of the hazard, but with many systems not receiving any regular monitoring, pollution events often go undetected. We developed toxicological risk assessment models for acute and chronic exposure to pollutants that incorporate the probabilities that the public will come into contact with undetected pollution events, to identify the level of risk a system poses in regards to the pollutant. As a proof of concept, we successfully demonstrated that the models could be applied to determine probabilities of acute and chronic illness types related to recreational activities in waterbodies containing cyanotoxins. Using the acute model, we identified lakes that present a 'high' risk to develop Day Away From Work illness, and lakes that present a 'low' or 'medium' risk to develop First Aid Cases when used for swimming. The developed risk models succeeded in categorising lakes according to their risk level to the public in an objective way. Modelling by how much the probability of public exposure has to decrease to lower the risks to acceptable levels will enable authorities to identify suitable control measures and monitoring strategies. We suggest broadening the application of these models to other contaminants.

- by Estela Stenico and +2
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- Cyanobacteria, Eutrophication, Genotoxicity, Allium Cepa
- by Dane Hardin and +1
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- Marine Biology, Global Health, Invertebrates, Cyanobacteria
- by Riks Laanbroek
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- Ecological Engineering, Ecological Modeling, Freshwater Biology, Life Sciences

The present paper is intended to serve as alarm in order to sharpen the attention of scientists to the benthic heterocytous cyanoprokaryote Calothrix confervicola, which seems to be the most probable potential causative agent for a human skin irritation (seewed dermatitis, or swimmer's itch), detected recently in one site on the southern Black Sea coast of Bulgaria.

- by Maya Stoyneva and +1
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- Algae, Cyanobacterial Toxins, Cyanotoxins
- by Haihong Song
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- Cyanobacteria, Adsorption, Biodegradation, Cyanobacterial Toxins

The occurrence of volatile nitrogen-containing compounds in
the cyanobacterium Aphanizomenon flos-aquae has been studied. Twenty
compounds belonging to four groups—amides of carboxylic and fatty acids,
heterocyclic compounds and their derivatives, aromatics, and alkoxyamines
and amides were identified by gas chromatography–mass spectrometry that
used serially coupled capillary columns with different polarity of stationary
phases. Distribution of bioactive non-toxic and toxic nitrogen-containing
metabolites in cyanobacteria are discussed