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Littérature scientifique sur le sujet « Cyanobacterial toxins Analysis »

Auteur : Grafiati

Publié le 4 juin 2021

Mis à jour le 1 février 2022

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Articles de revues sur le sujet "Cyanobacterial toxins Analysis"

Codd, Geoffrey A., James S. Metcalf, Clive J. Ward, Kenneth A. Beattie, Steven G. Bell, Kunimitsu Kaya et Grace K. Poon. « Analysis of Cyanobacterial Toxins by Physicochemical and Biochemical Methods ». Journal of AOAC INTERNATIONAL 84, n^o 5 (1 septembre 2001) : 1626–35. http://dx.doi.org/10.1093/jaoac/84.5.1626.

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Abstract Cyanobacteria (blue-green algae) produce a wide range of low molecular weight metabolites that include potent neurotoxins, hepatotoxins, and cytotoxins. The accumulation of such toxins in freshwaters, and in brackish and marine waters presents hazards to human and animal health by a range of exposure routes. A review is presented of developments in the detection and analysis of cyanobacterial toxins, other than bioassays, including application of physicochemical, immunoassays, and enzyme-based methods. Analytical requirements are considered with reference to recently derived guideline levels for the protection of health and to the availability, or otherwise, of purified, quantitative cyanobacterial toxin standards.

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Mohamad, Rohaslinda, Mohd Rafatullah, Tengku Yusof, Yi Sim, Norli Ismail et Japareng Lalung. « Detection of Microcystin (Mcye) Gene in Recreational Lakes in Miri, Sarawak, Malaysia ». Current World Environment 11, n^o 3 (25 décembre 2016) : 690–99. http://dx.doi.org/10.12944/cwe.11.3.02.

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Toxic cyanobacteria blooms became a worldwide problems as many countries encounter the presence of the blooms in most of water bodies. As part to develop monitoring of cyanobacterial toxins in Malaysia, samples taken in twelve points in five different lakes in Miri, Sarawak. Polymerase chain reaction (PCR) amplification of cyanobacterial 16S rRNA were carried out to detect the presence of cyanobacteria in the water samples. Cyanobacterial 16S rRNA were detected in all the samples collected. While molecular analysis for detection of cyanobacterial toxin encoding gene were done using specific primers. PCR amplification of cyanobacterial toxin-encoding gene were carried using the combination of forward primer; mcyE-F2 and reverse primer; mcyE-R4 to amplify generic microcystin (mcyE) gene in the samples. Out of twelve samples collected, microcystin (mcyE) producing gene was detected in one of the samples tested. Presence of microcystin encoding gene indicates the risk of cyanobacterial toxins in Miri, Sarawak.

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Kormas, Konstantinos Ar, et Despoina S. Lymperopoulou. « Cyanobacterial Toxin Degrading Bacteria : Who Are They ? » BioMed Research International 2013 (2013) : 1–12. http://dx.doi.org/10.1155/2013/463894.

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Cyanobacteria are ubiquitous in nature and are both beneficial and detrimental to humans. Benefits include being food supplements and producing bioactive compounds, like antimicrobial and anticancer substances, while their detrimental effects are evident by toxin production, causing major ecological problems at the ecosystem level. To date, there are several ways to degrade or transform these toxins by chemical methods, while the biodegradation of these compounds is understudied. In this paper, we present a meta-analysis of the currently available 16S rRNA andmlrA(microcystinase) genes diversity of isolates known to degrade cyanobacterial toxins. The available data revealed that these bacteria belong primarily to the Proteobacteria, with several strains from the sphingomonads, and one from each of theMethylobacillusandPaucibactergenera. Other strains belonged to the generaArthrobacter, Bacillus, andLactobacillus. By combining the ecological knowledge on the distribution, abundance, and ecophysiology of the bacteria that cooccur with toxic cyanobacterial blooms and newly developed molecular approaches, it is possible not only to discover more strains with cyanobacterial toxin degradation abilities, but also to reveal the genes associated with the degradation of these toxins.

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Ikehara, Tsuyoshi, Kyoko Kuniyoshi, Haruyo Yamaguchi, Yuuhiko Tanabe, Tomoharu Sano, Masahiro Yoshimoto, Naomasa Oshiro, Shihoko Nakashima et Mina Yasumoto-Hirose. « First Report of Microcystis Strains Producing MC-FR and -WR Toxins in Japan ». Toxins 11, n^o 9 (9 septembre 2019) : 521. http://dx.doi.org/10.3390/toxins11090521.

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Microcystins (MCs) are a group of cyclic heptapeptide hepatotoxins produced by Microcystis and several other genera of cyanobacteria. Many structural variants have been characterized using various methods such as liquid chromatography–mass spectrometry (LC-MS) analysis, enzyme-linked immunosorbent assay (ELISA) and protein phosphatase 2A (PP2A) inhibition assay. The representative MC, MC-LR, and related cyanobacterial toxins strongly inhibit PP2A activity and can therefore be assayed by measuring the extent of PP2A inhibition. However, these methods require reference toxin standards for the quantification and identification of known MCs. To obtain various MC-producing cyanobacterial strains, we surveyed and collected MC-producing cyanobacteria from environmental sources of water in Okinawa, Japan. Using a dual assay (LC-MS analysis and PP2A inhibition assay), we identified and isolated Microcystis strains producing five MC variants (MC-LR, -RR, -LA, -FR and -WR). Approximately 4 mg of MC-WR and -FR toxins were purified from the laboratory culture of the Microcystis isolate NIES-4344. Pure MC-WR and -FR variants were prepared for future use as toxin standards in LC-MS analysis. Phylogenetic analysis based on ftsZ revealed that the NIES-4344 strain belongs to the identified groups in Microcystis aeruginosa. This is the first report of Microcystis strains producing mainly MC-WR and -FR toxins in Japan.

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Andeden, Enver Ersoy, Sahlan Ozturk et Belma Aslim. « Antiproliferative, neurotoxic, genotoxic and mutagenic effects of toxic cyanobacterial extracts ». Interdisciplinary Toxicology 11, n^o 4 (1 décembre 2018) : 267–74. http://dx.doi.org/10.2478/intox-2018-0026.

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Abstract Cyanobacteria are the rich resource of various secondary metabolites including toxins with broad pharmaceutical significance. The aim of this work was to evaluate the antiproliferative, neurotoxic, genotoxic and mutagenic effects of cyanobacterial extracts containing Microcystin-LR (MCLR) in vitro. ELISA analysis results showed that MCLR contents of five cyanobacterial extracts were 2.07 ng/mL, 1.43 ng/mL, 1.41 ng/mL, 1.27 ng/mL, and 1.12 ng/mL for Leptolyngbya sp. SB1, Phormidium sp. SB4, Oscillatoria earlei SB5, Phormidium sp. SB2, Uncultured cyanobacterium, respectively. Phormidium sp. SB4 and Phormidium sp. SB2 extracts had the lowest neurotoxicity (86% and 79% cell viability, respectively) and Oscillatoria earlei SB5 extracts had the highest neurotoxicity (47% cell viability) on PC12 cell at 1000 µg/ml extract concentration. Leptolyngbya sp. SB1 and Phormidium sp. SB2 showed the highest antiproliferative effect (92% and 77% cell death) on HT29 cell. On the other hand, all concentrations of five toxic cyanobacterial extracts induced DNA damage between 3.0% and 1.3% of tail intensity and did not cause any direct mutagenic effect at the 1000 µg/plate cyanobacterial extracts. These results suggest that cyanobacteria-derived MCLR is a promising candidate for development of effective agents against colon cancer.

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Everson, Sally, Larelle Fabbro, Susan Kinnear, Geoff Eaglesham et Paul Wright. « Distribution of the cyanobacterial toxins cylindrospermopsin and deoxycylindrospermopsin in a stratified lake in north-eastern New South Wales, Australia ». Marine and Freshwater Research 60, n^o 1 (2009) : 25. http://dx.doi.org/10.1071/mf08115.

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This paper describes the vertical water column distribution of the cyanobacterial toxins cylindrospermopsin and deoxycylindrospermopsin in a water body containing the cyanobacteria Aphanizomenon ovalisporum and Cylindrospermopsis raciborskii. The study site was Cobaki Village Lake, a small stratified anthropogenic lake in north-eastern New South Wales, Australia. Water quality analysis indicated that stratification and oxygenation of the water column were significant in both the distribution of the cyanobacterial populations and their associated toxin concentrations. Toxin was distributed throughout the entire water column, but the highest concentrations were recorded in the hypolimnion. Maximum toxin concentrations were detected in February 2007 (38.2 μg L–1 cylindrospermopsin (CYN) and 42.2 μg L–1 deoxy-CYN). The relative distribution of CYN and deoxy-CYN paralleled the distribution of NH3H and NOX within the water column, with oxygenated chemical species dominating above 15 m and de-oxygenated chemical species dominating below 15 m. Cyanobacterial cell concentrations were highest in the oxic, warm and low conductivity waters of the epilimnion and cyanobacterial species succession was associated with nutrient and trace-metal depletion in this surface layer. These research findings are directly relevant to the management of water supplies affected by toxic blue-green algal blooms, particularly with respect to the considered placement of off-take devices to avoid layers of cyanobacterial cell and toxin concentrations.

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Khomutovska, Nataliia, Małgorzata Sandzewicz, Łukasz Łach, Małgorzata Suska-Malawska, Monika Chmielewska, Hanna Mazur-Marzec, Marta Cegłowska et al. « Limited Microcystin, Anatoxin and Cylindrospermopsin Production by Cyanobacteria from Microbial Mats in Cold Deserts ». Toxins 12, n^o 4 (11 avril 2020) : 244. http://dx.doi.org/10.3390/toxins12040244.

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Toxic metabolites are produced by many cyanobacterial species. There are limited data on toxigenic benthic, mat-forming cyanobacteria, and information on toxic cyanobacteria from Central Asia is even more scarce. In the present study, we examined cyanobacterial diversity and community structure, the presence of genes involved in toxin production and the occurrence of cyanotoxins in cyanobacterial mats from small water bodies in a cold high-mountain desert of Eastern Pamir. Diversity was explored using amplicon-based sequencing targeting the V3-V4 region of the 16S rRNA gene, toxin potential using PCR-based methods (mcy, nda, ana, sxt), and toxins by enzyme-linked immunosorbent assays (ELISAs) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Molecular identification of cyanobacteria showed a high similarity of abundant taxa to Nostoc PCC-73102, Nostoc PCC-7524, Nodularia PCC-935 and Leptolyngbya CYN68. The PCRs revealed the presence of mcyE and/or ndaF genes in 11 samples and mcyD in six. The partial sequences of the mcyE gene showed high sequence similarity to Nostoc, Planktothrix and uncultured cyanobacteria. LC-MS/MS analysis identified six microcystin congeners in two samples and unknown peptides in one. These results suggest that, in this extreme environment, cyanobacteria do not commonly produce microcystins, anatoxins and cylindrospermopsins, despite the high diversity and widespread occurrence of potentially toxic taxa.

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Moradinejad, Saber, Hana Trigui, Juan Francisco Guerra Maldonado, Jesse Shapiro, Yves Terrat, Arash Zamyadi, Sarah Dorner et Michèle Prévost. « Diversity Assessment of Toxic Cyanobacterial Blooms during Oxidation ». Toxins 12, n^o 11 (20 novembre 2020) : 728. http://dx.doi.org/10.3390/toxins12110728.

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Fresh-water sources of drinking water are experiencing toxic cyanobacterial blooms more frequently. Chemical oxidation is a common approach to treat cyanobacteria and their toxins. This study systematically investigates the bacterial/cyanobacterial community following chemical oxidation (Cl2, KMnO4, O3, H2O2) using high throughput sequencing. Raw water results from high throughput sequencing show that Proteobacteria, Actinobacteria, Cyanobacteria and Bacteroidetes were the most abundant phyla. Dolichospermum, Synechococcus, Microcystis and Nostoc were the most dominant genera. In terms of species, Dolichospermum sp.90 and Microcystis aeruginosa were the most abundant species at the beginning and end of the sampling, respectively. A comparison between the results of high throughput sequencing and taxonomic cell counts highlighted the robustness of high throughput sequencing to thoroughly reveal a wide diversity of bacterial and cyanobacterial communities. Principal component analysis of the oxidation samples results showed a progressive shift in the composition of bacterial/cyanobacterial communities following soft-chlorination with increasing common exposure units (CTs) (0–3.8 mg·min/L). Close cyanobacterial community composition (Dolichospermum dominant genus) was observed following low chlorine and mid-KMnO4 (287.7 mg·min/L) exposure. Our results showed that some toxin producing species may persist after oxidation whether they were dominant species or not. Relative persistence of Dolichospermum sp.90 was observed following soft-chlorination (0.2–0.6 mg/L) and permanganate (5 mg/L) oxidation with increasing oxidant exposure. Pre-oxidation using H2O2 (10 mg/L and one day contact time) caused a clear decrease in the relative abundance of all the taxa and some species including the toxin producing taxa. These observations suggest selectivity of H2O2 to provide an efficient barrier against toxin producing cyanobacteria entering a water treatment plant.

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Metcalf, J. S., et G. A. Codd. « Analysis of Cyanobacterial Toxins by Immunological Methods ». Chemical Research in Toxicology 16, n^o 2 (février 2003) : 103–12. http://dx.doi.org/10.1021/tx0200562.

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Kleinteich, J., F. Hildebrand, S. A. Wood, S. Ciŕs, R. Agha, A. Quesada, D. A. Pearce, P. Convey, F. C. K̈pper et D. R. Dietrich. « Diversity of toxin and non-toxin containing cyanobacterial mats of meltwater ponds on the Antarctic Peninsula : a pyrosequencing approach ». Antarctic Science 26, n^o 5 (14 mai 2014) : 521–32. http://dx.doi.org/10.1017/s0954102014000145.

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AbstractDespite their pivotal role as primary producers, there is little information as to the diversity and physiology of cyanobacteria in the meltwater ecosystems of polar regions. Thirty cyanobacterial mats from Adelaide Island, Antarctica were investigated using 16S rRNA gene pyrosequencing and automated ribosomal intergenic spacer analysis, and screened for cyanobacterial toxins using molecular and chemical approaches. A total of 274 operational taxonomic units (OTUs) were detected. The richness ranged between 8 and 33 cyanobacterial OTUs per sample, reflecting a high mat diversity. Leptolyngbya and Phormidium (c. 55% and 37% of the OTUs per mat) were dominant. Cyanobacterial community composition was similar between mats, particularly those obtained from closely adjacent locations. The cyanotoxin microcystin was detected in 26 of 27 mats (10–300 ng g-1 organic mass), while cylindrospermopsin, detected for the first time in Antarctica, was present in 21 of 30 mats (2–156 ng g-1 organic mass). The latter was confirmed via liquid chromatography-mass spectrometry and by the presence of the cyrAB and cyrJ genes. This study demonstrates the usefulness of pyrosequencing for characterizing diverse cyanobacterial communities, and confirms that cyanobacteria from extreme environments produce a similar range of cyanotoxins as their temperate counterparts.

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Thèses sur le sujet "Cyanobacterial toxins Analysis"

Froscio, Suzanne M. « Investigation of the mechanisms involved in cylindrospermopsin toxicity : hepatocyte culture and reticulocyte lysate studies ». Title page, contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phf938.pdf.

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Bibliography: leaves 121-139. The aim of this study was to determine the extent to which protein synthesis inhibition, lowered glutathione (GSH) levels and toxin metabolism contribute to the toxicity of cyclindrospermopsin. Both hepatocyte cultures and reticulocyte lysates were utilized as in vitro tools of investigation. The findings imply that the inhibition of protein synthesis by direct action of the toxin cannot be considered a primary cause of hepatocyte cell death over an acute time frame. Cytochrome P450-derived metabolites may play a crucial role in cytotoxicity, and the toxicity process does not appear to involve oxidative damage.

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Coyle, Sadie Marie. « Investigations of microcystins (cyanobacterial peptide toxins) : detection, purification and analysis ». Thesis, Robert Gordon University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360091.

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Masango, Mxolisi Goodwill. « A comparative analysis of the cytotoxicity of cyanotoxins using in vitro (cell culture) and in vivo (mouse) assays ». Diss., Pretoria : [s.n.], 2007. http://upetd.up.ac.za/thesis/available/etd-05122008-100402/.

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Humpage, Andrew Raymond. « Tumour promotion by the cyanobacterial toxin microcystin / ». Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phh9258.pdf.

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DeMarco, Jonathan R. « Cyanobacterial Blooms in Chautauqua Lake, NY : Nutrient Sources and Toxin Analyses ». Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1625052848648708.

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Kuno, Sotaro. « Genetic analysis of host-phage interactions involving the toxic cyanobacterium Microcystis aeruginosa ». Kyoto University, 2013. http://hdl.handle.net/2433/175039.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第17610号
農博第1972号
新制||農||1008(附属図書館)
学位論文||H25||N4731(農学部図書室)
30376
京都大学大学院農学研究科応用生物科学専攻
(主査)教授左子芳彦, 教授平田孝, 教授澤山茂樹
学位規則第4条第1項該当

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Chapman, Ian. « Developing new approaches for monitoring and controlling the toxic cyanobacterium Microcystis through flow-cytometric analysis ». Thesis, Bournemouth University, 2017. http://eprints.bournemouth.ac.uk/29267/.

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Biological hazards principally those produced by microorganisms have been identified as a primary concern for drinking water, putting human health at great risk. One major threat to drinking water security is associated with cyanobacteria, where bloom-forming genera like Microcystis can cause anoxic environments, damage filtration systems and produce potent toxins. As future projections of climate change and anthropogenic nutrient loading continue to favour the growth of Microcystis it adds further stress to an already limited supply of clean drinking water, highlighting the need to develop new monitoring and controls of freshwater systems. Here, high through-put, real time protocols using a relatively low cost flow cytometer were developed for identifying, enumerating and analysing the single cell physiology of Microcystis. These methodologies were then adopted for monitoring environmental populations in drinking water supplies and assessed the potential of novel biological, chemical and biochemical controls. Measurements based on light scatter and fluorescence emissions from uni-algal Microcystis culture lines and fresh isolates (derived from a novel technique) were used as calibration for a flow cytometric assay to monitor Microcystis-like cells in a local reservoir. The findings for the first time reported seasonal patterns of Microcystis in a British lowland reservoir, revealing increased local densities during late summer and early autumn with temperature being the most significant factor. To assess potential Microcystis controls the mortality rates in laboratory experiments were also sampled through flow cytometry incorporating molecular probes, which enabled the analysis of single-cell physiological states after exposure to particular stressors. A grazing experiment was carried out which examined the trophic interactions of a ciliate protist, Blepharisma americanum, against a toxic and non-toxic strain of Microcystis. B. americanum died in the presence of toxic Microcystis at the same rate as a nutrient-starved control and recorded no grazing effects on cyanobacterium densities despite ingestion being observed. In contrast, non-toxic Microcystis populations were controlled when grazed by B. americanum with ciliate populations increasing, providing further insight into their ecological role within the microbial loop. The results also contradicted previous experimental organisms which were found to feed on toxic microcystin-rich cyanobacterial cells, contributing to the theory that the secondary metabolite may function as an anti-predatory molecule. A cheap naturally degrading chemical agent (acetic acid) found to control terrestrial photoautotrophs was tested on a fresh isolate of Microcystis. Applications of acetic acid were trailed in parallel with of a well-known anti-cyanobacterial compound (hydrogen peroxide) resulting in the increased formation of reactive oxygen species (ROS), membrane permeability and consequently cell mortality. For the first time in cyanobacteria acetic acid was found to induce ROS and decrease densities. Although hydrogen peroxide had a more effective dose for dose control of Microcystis the concentrations were too high for UK operational limits, which have not been set for acetic acid. The results also highlighted that freshly isolated Microcystis require increased concentrations compared to established culture lines. The production of a biochemical control derived through filtered bi-products from a nutrient depleted Microcystis culture demonstrated an auto-induced sub-lethal and lethal effect on low and exponential Microcystis densities. The cytotoxic effect was dose dependant and only induced cell mortality under light conditions, indicating a potential for anti-Microcystis compounds. Results also emphasised the importance of rigorous testing of any control measure through various cell densities / population life cycles and environmental parameters. The flow cytometric monitoring protocols developed throughout this research can be used for accurate, real time measurements of cyanobacteria like Microcystis in aquatic systems. Enhanced by flow cytometry analysis all three biological, chemical and biochemical controls of Microcystis can potentially be integrated into water treatment management, thereby increasing drinking water security.

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Jia-YuChih et 池佳育. « Multivariate Analysis of the Relationships among Cyanobacterial Toxins and Odorants and Environmental Parameters in Reservoirs ». Thesis, 2019. http://ndltd.ncl.edu.tw/handle/jrq865.

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碩士
國立成功大學
環境工程學系
107
As cyanobacteria blooms often occur in many drinking water reservoirs globally, their harmful secondary metabolites has been received more concern. The concerned cyanobacterial metabolites include cyanotoxins and taste-and-odor (T＆O) compounds, since they may pose health risk or influence human perception of consumers. The most concerned cyanotoxins include microcystins and cylindrospermopsins, and the T＆O compounds include the earthy odorant compound, geosmin, the musty odorant compound, 2-methylisoborneol(2-MIB), and tobacco-like odorant compound, -cyclocitral, which were found in many reservoirs in Taiwan. To understand more about the link between the growth of cyanobacteria and the presence of the above mentioned harmful secondary metabolites, and water quality and environmental conditions, this study is aimed to analyze their relationships through statistical analysis. The data of cyanobacterial and metabolites were collected from the sampling activities for Taiwan’s reservoirs conducted in 2012 to 018, and the environmental data were obtained from the Environmental Protection on Administration and Central Weather Bureau in Taiwan. Then, the data were analyzed using principal components analysis, sensitivity analysis, and time-series correlation matrix. The results show that the main reason to increase the concentration of microcystins and cylindrospermopsins were the abundance of the main producers, Microcystis and Cylindrospermopsis, respectively, with phosphorus being the limited nutrient for Microcystis growth and microcystins, and -cyclocitral production. For other producers, they were affected by turbidity. Functional genes responsible for the production of the metabolites were highly correlated with the corresponding metabolites, which may be as indexes for risk assessment. Light intensity, pH value, and conductivity did not show good correlations with the studied metabolites, but they had impact on the final results of PCA. The results of the time-series analysis with correlation matrix showed that the relationships within cyanobacterial variables and meteorological variables were impacted by time series. Hence, to analyze the relationships within the metabolites and light intensity, temperature, rainfall, or wind speed should take the average value of the data from former time period.

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Yen, Hung-Kai, et 顏宏愷. « Analysis of Toxic Cyanobacteria and Cyanotoxins in Taiwan’s Reservoirs ». Thesis, 2009. http://ndltd.ncl.edu.tw/handle/13999916170514428848.

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博士
國立成功大學
環境工程學系碩博士班
97
Cyanobacteria are present in many drinking water reservoirs in Taiwan and the world, and some of them may produce cyanotoxins and release them to natural water bodies. However, the information relevant to the presence of toxic cyanobacteria and cyanotoxins in Taiwan’s drinking water reservoirs are very limited. Therefore, a systematic investigation of their occurrence is urgently needed. The objectives of this dissertation is to develop and apply different analytical approaches, including chemical and bio-molecular methods, for the determination of toxigenic cyanobacteria and cyanotoxins in Taiwan’s drinking water reservoirs and waterworks. In this dissertation, a solid phase extraction (SPE) coupled with liquid chromatography (LC)-mass spectrometry (MS) method was first developed to concentrate and detect nine commonly observed cyanobacterial toxins simultaneously, including six microcystins (MCs) congeners, nodularin (NOD), anatoxin-a (ATX) and cylindrospermopsin (CYN), in water samples. A surrogate standard (SS) and internal standard (IS) were applied in the analytical method for better quality control. The method detection limit (MDL) was 2-10 ng/L for MCs and NOD in pure water, and was 46 ng/L for ATX and 100 ng/L for CYN, respectively. In more complicated water matrix, reservoir water with high concentration of Microcystis spp., the MDL for the cyanotoxins increased by a factor of 3 to 10, with CYN = 500 ng/L as the highest. The analytical method developed was then applied to monitor two groups of cyanotoxins (MCs and ATX) in nine major drinking water reservoirs and seven associated waterworks. Monitoring results suggested that microcystins were present in all the drinking water reservoirs studied, and some of them had concentration higher than the WHO guideline of MC-LR (1 μg/L). In addition, ATX was also found in four reservoirs, in Kinmen Island. In order to correlate the two groups of cyanobacterial metabolites (cyanotoxins and off-flavour compounds) and other environmental parameters, 22 water quality and meteorological parameters were monitored for two source waters (Moo Tan Reservoir, MTR, and Tseng Wen Reservoir, TWR) in south Taiwan from August 2003 to April 2005. Monitoring results showed that the cyanotoxins and off-flavour compounds (2-MIB and Geosmin) were present in the source waters. Concentrations of 2–30 ng/L of 2-MIB was observed for the two reservoirs, while that of the summation of five microcystin congeners measured were between 30 and 340 ng/L. The concentration of both 2-MIB and microcystins showed higher concentrations in warmer seasons. A stepwise regression technique was employed to correlate 2-MIB and MCs concentrations with all the corresponding water quality and meteorological parameters. Good correlations among 2-MIB concentration, MC concentration, water temperature and air temperature were found in the water samples collected from both reservoirs. The correlations may provide a simple means for the water utility to anticipate the two groups of cyanobacterial metabolites in the two source waters. In addition to the two reservoirs monitored, the cyanobacterial metabolites were also commonly observed in reservoirs and their associated waterworks in Kinmen Island. To have a better water treatment efficiency in Kinmen’s waterworks, a more precise understanding of the algal metabolites at different time and depths in the water sources as well as the change of metabolites in the treatment processes are needed. Therefore, the diurnal concentration change of the two major cyanobacterial metabolites were monitored in a major source water (Tai Lake Reservoir, TLR and major waterworks (Tai Lake Waterworks, TLW) of the island. The samples for the reservoir water were collected at/near the water intake, and one of them was sampled at 4 different depths. Most of the parameters measured varied significantly at different depths and different time, and only 2-MIB concentration remained almost constant through out the 24 hour period and at different depths. This may imply that 2-MIB was likely to uniformly distribute in the reservoir water. For most of the cyanobacteria and cyanobacterial metabolites measured, no strong correlations were observed. However, a good correlation between Microcystis spp. and MCs concentrations was found, indicating that the probable relationship between the toxins and their producers. This simple correlation may also be used in the estimation of the cell-bound and dissolved concentration of MCs in the reservoir water. For the samples collected for the waterworks, more than 98% of cyanobacteria were removed in the treatment processes, and most were removed at the dissolved air floatation (DAF) unit. Although the overall removal efficiency of microcystins and 2-MIB in TLW is >75%, unlike that for the cyanobacertia cells, only 20-30% were removed before DAF. This may be attributed to that DAF cannot effectively remove dissolved microcystins that was already present in the raw water or was released into water from the breakage of mcirocystis cells by pre-chlorination. Compared with other conventional waterworks, the slow sand filters may provide an extra 20-30% of 2-MIB removal for TLW. Finally, in order to identify the potential MC producers in MTR and its associated waterworks, two molecular methods were developed and employed to determine the DNA sequences and characteristics of cyanobacteria community, and to quantify the functional gene concentrations in water samples. Four toxigenic Microcystis spp. strains (TWNCKU01 - TWNCKU04) were first isolated from different locations in MTR. After laboratory cultivation, two of the strains, TWNCKU01 and TWNCKU02, were found to mainly produce MC-RR, and another two may produce MC-LR, -RR and -YR at different ratios. The bio-molecular results based on mcyA and mcyB sequencing showed that all the strains are toxic Microcystis spp. and may produce MCs. The two higher diversified regions, PC-IGS (cpcB) and 16S-23S rDNA (ITS), are used to further identify the four strains. In addition, the ITS region was also used in DGGE for the construction of a clone library and bio-makers for 11 strains observed in MTR. These ITS-DGGE biomarkers were successfully applied in monitoring the community changes of potential microcystin producers over a period of 5 years. To develop a rapid method for quantifying microcystin-producing genes, two highly specific primers were designed based on UPL probes to measure mcyB and cpcB concentrations in water samples, where the former one represents gene concentration for MC producers and the latter one is for gene concentrations of cyanobacteria. In the long term monitoring results of MTR, 39 of the 41 DGGE samples contained Microcystis spp., with 36 samples being TWNCKU01 or -02, the MC-RR producers. In addition, 3 of the samples contain Planktothrix spp. After analyzing the data from UPL-based real time PCR and other reservoir water quality parameters, including Microcystis cell counts, MC concentrations, and others, the gene concentrations based on UPL-mcyB correlates well with MC-RR concentrations, the major toxin type in the reservoir, and water temperature. In addition, the gene concentrations based on UPL-cpcB correlate with cyanobacteria as well as Microcystis cell concentrations in the water samples. Both DGGE and UPL-probe methods were further successfully applied in the water samples from MTW. Although toxin concentrations were very low, the DGGE bands clearly demonstrated the presence of MC-RR producers in both process water and finished water samples. The results of UPL-real time PCR also showed that mcyB concentrations were detected to be around 200 copies/mL in the finished samples, proving that Microcystis cells may penetrate through the treatment processes and pose a potential risk in drinking water systems.

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Jonlija, Miroslava. « Assessment of toxic cyanobacterial abundance at Hamilton Harbour from analysis of sediment and water ». Thesis, 2014. http://hdl.handle.net/10012/8429.

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The western embayment of Lake Ontario, Hamilton Harbour, is one of the most polluted sites in the Laurentian Great Lakes and in recent years has seen a reoccurrence of cyanobacterial blooms. This study uses a multidisciplinary approach to examine the presences of toxic Cyanobacteria in the harbour in order to gain insight into these recurrent blooms. Microscopic analyses of phytoplankton samples collected during the 2009 summer-fall sampling season from two locations within the harbour showed the spatial and seasonal diversity of the contemporary cyanobacterial community. Microcystis colonies relative abundances in relation to total algal numbers were estimated. The lowest and highest relative abundances of Microcystis in the phytoplankton population were 0.6% and 9.7%, respectively, and showed seasonal variability between stations. Fourteen cyanobacterial genera comprising six families and three orders were identified and for which the most abundant filamentous genera during the summer-fall sampling season were Planktothrix, Aphanizomenon and Limnothrix. Potential microcystin producers Microcystis, Planktothrix, Aphanizomenon and Dolichospermum were also present and during the sampling period Microcystis was recorded at both stations on all dates, however, its relative abundance was below 10 % throughout the study period. The composition and abundance of filamentous cyanobacteria were observed to be positively statistically correlated to water quality environmental parameters dissolved nitrates (NO3/NO2), dissolved inorganic carbon (DIC), and conductivity. Redundancy analysis (RDA) found that 53.35% total variance of Aphanizomenon was correlated to low water column NO3/NO2 and conductivity, and higher water column DIC. 58.13% of the relative abundance of Planktothrix was correlated to high concentrations of dissolved nitrates, while 51.69% of total variance of Limnothrix was correlated to higher DIC and lower water column dissolved nitrate concentrations. Information about past cyanobacterial communities was obtained from the sediment core analysis, using paleolimnological and modern molecular methods. The age of the 100.5 cm long sediment core retrieved from the deepest part of Hamilton Harbour was established to be 140 years (1869-2009), using the Constant Rate of Supply (CRS) 210Pb age model. This age was not sufficient to provide information of harbour’s environmental conditions, presence of the blooms, and triggers for their occurrence before European settlement in the area. Results of the HPLC analysis of fossil pigments indicated that the dominant members of the algal community have not changed over the 140 years and that cyanobacteria were regular members of the phytoplankton community. The composition of the major chlorophyll pigments indicated high presence of Chlorophyta and Bacillariophyta in the harbour at all times. The main algal groups identified on the basis of marker pigments presence, besides the Chlorophyta and Bacillariophyta, were the Dinophyta and the Cryptophyta. The presence of a scytonemin derivative, compound B, indicated that cyanobacterial blooms were occurring in past, before the first officially recorded blooms in the 1960s. Cyanobacterial pigments presence indicated that Cyanobacteria have been a regular but not dominant feature of Hamilton Harbour phytoplankton in the past. To our knowledge, this study is the first one examining fossil pigments from Hamilton Harbour. Results of the PCR-DGGE molecular analysis of 16S rRNA-V3 gene fragments from sedimentary DNA revealed the presence of thirteen cyanobacterial genotypes. The temporal change in the cyanobacterial community composition was indicated by the increasing number of species over time, from the oldest to the most recent sediment layers. The deepest sediment strata showed the lowest number (two bands) and intensity of bands. The most recent sediment layer had the greatest numbers (11) and intensity of bands. This increased diversity indicated changing environmental conditions in the harbour, primarily nutrient pollution and worsening water quality. Results of the PCR-DGGE molecular analysis of mcyE-AMT gene fragments showed that Microcystis aeruginosa and Planktothrix rubescens were two microcystin producers present in Hamilton Harbour over the last 80 years. The persistent presence and resilience of these two genera indicated a more serious and longer-term issue of toxic blooms than previously recognized. Historical records show that noticeable anthropogenic impact on Lake Ontario environment has been measurable since the 1780s, the first dramatic impact on the Lake Ontario watershed was evident from the mid1880s, the earliest evidence of eutrophication in the lake occurred between 1820 and 1850, while human induced environmental changes in Hamilton Harbour date back ca. 350 years. In the 1960s, cyanobacterial blooms were first officially recognized in the harbour and the lower Great Lakes. The present research is the first report of the mcyE module and AMT domain of microcystin genes being amplified from sediment of North American lakes, and showed that toxic Cyanobacterial have been regular members of Hamilton Harbour phytoplankton community for almost a century. This research considerably deepened the knowledge of the past toxic cyanobacterial blooms in Hamilton Harbour and their possible causes. It also showed that in the absence of historical records, both the PCR-DGGE method and the mcyE-AMT gene may be used for reconstruction of the past toxic blooms not only in the Laurentian Great Lakes, but also in other aquatic regions of the world impacted by toxic cyanobacterial blooms. Also, it demonstrated the utility of the combined molecular and paleolimnological analyses, which might become a useful tool in the determination of the bloom causes factors and in the mitigation of the future production of toxic blooms.

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Livres sur le sujet "Cyanobacterial toxins Analysis"

Meriluoto, Jussi. Liquid chromatographic analysis of cyanobacterial peptide hepatotoxins. Åbo : Åbo Akademis förlag, 1990.

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Toxic : Cyanobacterial monitoring and cyanotoxin analysis. Åbo : Åbo Akademi University Press, 2005.

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Wei nang zao du su fen xi jian ce ji shu : Analysis and detection technology of microcystin. Beijing : Hua xue gong ye chu ban she, 2010.

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A, Codd G., et International Symposium on Detection Methods for Cyanobacterial (Blue-Green Algal) Toxins (1st : 1993 : University of Bath), dir. Detection methods for cyanobacterial toxins. Cambridge, UK : Royal Society of Chemistry, 1994.

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DETECTION METHODS FOR CYANOBAC (Special Publications). Royal Society of Chemistry, 1994.

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Falconer, Ian Robert. Algal Toxins in Seafood and Drinking Water. Academic Press, 1993.

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Algal Toxins in Seafood and Drinking Water. Academic Press, 1993.

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Chapitres de livres sur le sujet "Cyanobacterial toxins Analysis"

Vasas, Gábor. « Capillary Electrophoresis of Cyanobacterial Toxins ». Dans Handbook of Cyanobacterial Monitoring and Cyanotoxin Analysis, 258–62. Chichester, UK : John Wiley & Sons, Ltd, 2017. http://dx.doi.org/10.1002/9781119068761.ch24.

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Lawton, Linda A., James S. Metcalf, Bojana Žegura, Ralf Junek, Martin Welker, Andrea Törökné et Luděk Bláha. « Laboratory analysis of cyanobacterial toxins and bioassays ». Dans Toxic Cyanobacteria in Water, 745–800. 2^e éd. Second edition. | Boca Rataon : CRC Press, an imprint of Informa, 2021. : CRC Press, 2021. http://dx.doi.org/10.1201/9781003081449-14.

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Ibelings, Bas W., et Karl E. Havens. « Cyanobacterial toxins : a qualitative meta–analysis of concentrations, dosage and effects in freshwater, estuarine and marine biota ». Dans Advances in Experimental Medicine and Biology, 675–732. New York, NY : Springer New York, 2008. http://dx.doi.org/10.1007/978-0-387-75865-7_32.

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Padisák, Judit, Ingrid Chorus, Martin Welker, Blahoslav Maršálek et Rainer Kurmayer. « Laboratory analyses of cyanobacteria and water chemistry ». Dans Toxic Cyanobacteria in Water, 689–743. 2^e éd. Second edition. | Boca Rataon : CRC Press, an imprint of Informa, 2021. : CRC Press, 2021. http://dx.doi.org/10.1201/9781003081449-13.

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Bláha, Luděk, Ana Maria Cameán, Valérie Fessard, Daniel Gutiérrez-Praena, Ángeles Jos, Benjamin Marie, James S. Metcalf et al. « Bioassay Use in the Field of Toxic Cyanobacteria ». Dans Handbook of Cyanobacterial Monitoring and Cyanotoxin Analysis, 272–79. Chichester, UK : John Wiley & Sons, Ltd, 2017. http://dx.doi.org/10.1002/9781119068761.ch27.

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Salmaso, Nico, Cécile Bernard, Jean-François Humbert, Reyhan Akçaalan, Meriç Albay, Andreas Ballot, Arnaud Catherine et al. « Basic Guide to Detection and Monitoring of Potentially Toxic Cyanobacteria ». Dans Handbook of Cyanobacterial Monitoring and Cyanotoxin Analysis, 46–69. Chichester, UK : John Wiley & Sons, Ltd, 2017. http://dx.doi.org/10.1002/9781119068761.ch6.

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Häggqvist, Kerstin, Reyhan Akçaalan, Isidora Echenique-Subiabre, Jutta Fastner, Mária Horecká, Jean-François Humbert, Katarzyna Izydorczyk et al. « Case Studies of Environmental Sampling, Detection, and Monitoring of Potentially Toxic Cyanobacteria ». Dans Handbook of Cyanobacterial Monitoring and Cyanotoxin Analysis, 70–83. Chichester, UK : John Wiley & Sons, Ltd, 2017. http://dx.doi.org/10.1002/9781119068761.ch7.

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Harada, Ken-ichi, Makoto Suzuki et Mariyo F. Watanabe. « Structural Analysis of Cyanobacterial Toxins ». Dans Detection Methods for Cynobacterial Toxins, 24–33. Elsevier, 1994. http://dx.doi.org/10.1533/9781845698164.1.24.

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« Detection and Analysis of Cylindrospermopsins and Microcystins ». Dans Cyanobacterial Toxins of Drinking Water Supplies, 185–211. CRC Press, 2004. http://dx.doi.org/10.1201/9780203022870.ch10.

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« Detection and Analysis of Cylindrospermopsins and Microcystins ». Dans Cyanobacterial Toxins of Drinking Water Supplies, 199–225. CRC Press, 2004. http://dx.doi.org/10.1201/9780203022870-16.

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Rapports d'organisations sur le sujet "Cyanobacterial toxins Analysis"

Pokrzywinski, Kaytee, Kaitlin Volk, Taylor Rycroft, Susie Wood, Tim Davis et Jim Lazorchak. Aligning research and monitoring priorities for benthic cyanobacteria and cyanotoxins : a workshop summary. Engineer Research and Development Center (U.S.), août 2021. http://dx.doi.org/10.21079/11681/41680.

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In 2018, the US Army Engineer Research and Development Center partnered with the US Army Corps of Engineers–Buffalo District, the US Environmental Protection Agency, Bowling Green State University, and the Cawthron Institute to host a workshop focused on benthic and sediment-associated cyanobacteria and cyanotoxins, particularly in the context of harmful algal blooms (HAB). Technical sessions on the ecology of benthic cyanobacteria in lakes and rivers; monitoring of cyanobacteria and cyanotoxins; detection of benthic and sediment-bound cyanotoxins; and the fate, transport, and health risks of cyanobacteria and their associated toxins were presented. Research summaries included the buoyancy and dispersal of benthic freshwater cyanobacteria mats, the fate and quantification of cyanotoxins in lake sediments, and spatial and temporal variation of toxins in streams. In addition, summaries of remote sensing methods, omic techniques, and field sampling techniques were presented. Critical research gaps identified from this workshop include (1) ecology of benthic cyanobacteria, (2) identity, fate, transport, and risk of cyanotoxins produced by benthic cyanobacteria, (3) standardized sampling and analysis protocols, and (4) increased technical cooperation between government, academia, industry, nonprofit organizations, and other stakeholders. Conclusions from this workshop can inform monitoring and management efforts for benthic cyanobacteria and their associated toxins.

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