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Sarkar A, Rajarathinam R, Kumar PS, Rangasamy G. Maximization of growth and lipid production of a toxic isolate of Anabaena circinalis by optimization of various parameters with mathematical modeling and computational validation. J Biotechnol 2022; 357:38-46. [PMID: 35952899 DOI: 10.1016/j.jbiotec.2022.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 07/28/2022] [Accepted: 08/04/2022] [Indexed: 10/15/2022]
Abstract
Toxic cyanobacterial blooms are recurrent for few decades throughout the globe, due to climate change, atmospheric warming and various anthropogenic activities with severe impacts of potential toxins on various ecosystems finally affecting the entire environment. These cyanobacteria are merely unexplored regarding their biochemical components except toxins. Variable influences and interactions of different factors including nitrogen, carbon, and availability of light are well known to crucially regulate cyanobacterial growth and metabolism. Thus, current research work is motivated for the evaluation and optimization of the effects of the aforementioned vital factors for improvement of biomass and lipid production of a freshwater, toxic strain of Anabaena circinalis. The modelling and optimization of factors such as nitrogen, light intensity and bicarbonate concentration (source of carbon) to maximize growth and lipid production were based on 20 design point experiments by Response Surface Methodology (RSM) and optimized values were further improved and validated by Particle Swarm Optimization (PSO) algorithm. The maximum optima were obtained 1.829 g L-1 and 39.64 % for biomass production and lipid content respectively from PSO optimization with two different sets of optimal values of factors. It shows 0.44 % and 2.77 % higher values of responses than that of RSM optimization. These asynchronous findings pioneered the enhanced lipid accumulation as well as the growth of a toxic cyanobacterium by optimizing interaction effects of culture conditions through various statistical and computational approaches.
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Affiliation(s)
- Aratrika Sarkar
- Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India
| | - Ravikumar Rajarathinam
- Center for Bioenergy and Bioproduct Development (CBBD), Department of Biotechnology, Vel Tech Rangarajan Dr. Sagunthala R&D Institute of Science and Technology, Avadi, Chennai 600062, India.
| | - P Senthil Kumar
- Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Kalavakkam, Chennai 603 110, India; Centre of Excellence in Water Research (CEWAR), Sri Sivasubramaniya Nadar College of Engineering, Kalavakkam, Chennai 603 110, India.
| | - Gayathri Rangasamy
- University Centre for Research and Development & Department of Civil Engineering, Chandigarh University, Gharuan, Mohali, Punjab - 140413, India
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Sarkar A, Rajarathinam R, Venkateshan RB. A comparative assessment of growth, pigment and enhanced lipid production by two toxic freshwater cyanobacteria Anabaena circinalis FSS 124 and Cylindrospermopsis raciborskii FSS 127 under various combinations of nitrogen and phosphorous inputs. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:15923-15933. [PMID: 33247403 DOI: 10.1007/s11356-020-11754-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 11/18/2020] [Indexed: 06/12/2023]
Abstract
Nitrogen and phosphorous are important nutritional regulators for the growth of cyanobacteria, thereby having a significant impact in bloom formation by toxic species. Usage of toxic cyanobacteria for increasing valuable metabolite production by nutrient manipulation is still unexplored. Hence, the current work is aimed to estimate and compare growth, pigment, and increased lipid production coupled with the identification of fatty acids between two toxic strains-Anabaena circinalis FSS 124 and Cylindrospermopsis raciborskii FSS 127 under various combinations of these two nutrients. Low level of nitrogen and phosphorous enhanced lipid content in both strains (˃ 20% and 30% respectively) and C. raciborskii, respectively. Lipid productivity in low phosphorous concentration (P0.5) was achieved significantly high in C. raciborskii. Similarly, a substantial amount of carotenoids was obtained at reduced nitrogen and phosphorous in C. raciborskii accompanied by lessened growth and Chl a concentration. Unlikely, enough biomass (˃ 2 g L-1) was produced at high nutrient levels in both species. Comparative statistical significance (p < 0.05) was found between two species regarding biomass production, chlorophyll concentration, lipid content, and productivity and between these factors in each species under both nutrient variations. FAME of Cylindrospermopsis is composed of saturated fatty acids (˃ 50%) and MUFA (˃ 25%) while Anabaena contains PUFA (˃ 21%) additionally. However, the study highlights C. raciborskii as potential lipid and carotenoid producer at nutrient stress and finds a novel way to utilize these cyanobacterial biomasses, which cause immense environmental hazards and life threats.
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Affiliation(s)
- Aratrika Sarkar
- Bioenergy Research Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, affiliated to Anna University, Chennai, TN, India
| | - Ravikumar Rajarathinam
- Bioenergy Research Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, affiliated to Anna University, Chennai, TN, India.
| | - Ranganathan Budhi Venkateshan
- Bioenergy Research Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, affiliated to Anna University, Chennai, TN, India
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3
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Funari E, Manganelli M, Buratti FM, Testai E. Cyanobacteria blooms in water: Italian guidelines to assess and manage the risk associated to bathing and recreational activities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 598:867-880. [PMID: 28458204 DOI: 10.1016/j.scitotenv.2017.03.232] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 03/23/2017] [Accepted: 03/25/2017] [Indexed: 06/07/2023]
Abstract
Cyanobacteria thrive in many aquatic environments, where they can produce cyanotoxins with different toxicological profile. Anthropic pressure and climate changes are causing the expansion in terms of time and space of their blooms, increasing the concerns for human health in several exposure scenarios. Here the update of the Italian guidelines for the management of cyanobacterial blooms in bathing water is presented. A risk-based approach has been developed according to the current scientific knowledge on cyanobacteria distribution in the Italian Lakes and on chemical, toxicological and epidemiological aspects of different cyanotoxins, summarized in the first part of the paper. Oral, dermal and inhalation exposure to cyanotoxins, during recreational activities, are individually examined, to develop a framework of thresholds and actions aimed at preventing harmful effects for bathers. Guidelines, also by comparing international guidance values and/or guidelines, provide criteria to plan environmental monitoring activities, health surveillance and public communication systems. Finally the still important scientific gaps and research needs are highlighted.
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Affiliation(s)
- Enzo Funari
- Istituto Superiore di Sanità, Dept. of Environment and Health, Viale Regina Elena 299, 00161 Rome, Italy.
| | - Maura Manganelli
- Istituto Superiore di Sanità, Dept. of Environment and Health, Viale Regina Elena 299, 00161 Rome, Italy.
| | - Franca M Buratti
- Istituto Superiore di Sanità, Dept. of Environment and Health, Viale Regina Elena 299, 00161 Rome, Italy.
| | - Emanuela Testai
- Istituto Superiore di Sanità, Dept. of Environment and Health, Viale Regina Elena 299, 00161 Rome, Italy.
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4
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Akter S, Vehniäinen M, Spoof L, Nybom S, Meriluoto J, Lamminmäki U. Broad-Spectrum Noncompetitive Immunocomplex Immunoassay for Cyanobacterial Peptide Hepatotoxins (Microcystins and Nodularins). Anal Chem 2016; 88:10080-10087. [DOI: 10.1021/acs.analchem.6b02470] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sultana Akter
- Molecular
Biotechnology and Diagnostics, Department of Biochemistry, University of Turku, FI-20520 Turku, Finland
| | - Markus Vehniäinen
- Molecular
Biotechnology and Diagnostics, Department of Biochemistry, University of Turku, FI-20520 Turku, Finland
| | - Lisa Spoof
- Biochemistry,
Faculty of Science and Engineering, Åbo Akademi University, FI-20520 Turku, Finland
| | - Sonja Nybom
- Biochemistry,
Faculty of Science and Engineering, Åbo Akademi University, FI-20520 Turku, Finland
| | - Jussi Meriluoto
- Biochemistry,
Faculty of Science and Engineering, Åbo Akademi University, FI-20520 Turku, Finland
| | - Urpo Lamminmäki
- Molecular
Biotechnology and Diagnostics, Department of Biochemistry, University of Turku, FI-20520 Turku, Finland
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Mayer AMS, Murphy J, MacAdam D, Osterbauer C, Baseer I, Hall ML, Feher D, Williams P. Classical and Alternative Activation of Cyanobacterium Oscillatoria sp. Lipopolysaccharide-Treated Rat Microglia in vitro. Toxicol Sci 2016; 149:484-95. [PMID: 26609141 PMCID: PMC4900220 DOI: 10.1093/toxsci/kfv251] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The purpose of this investigation was to test the hypothesis that an in vitro exposure to cyanobacterium Oscillatoria sp. Lipopolysaccharide (LPS) might result in classical and alternative activation of rat neonatal microglia. Using Escherichia coli LPS-primed microglia as a positive control, this study revealed that treatment of rat microglia with Oscillatoria sp. LPS for 17 h in vitro resulted in both classical and alternative activation as well as concomitant pro-inflammatory and anti-inflammatory mediator release, in a concentration-dependent manner: (1) treatment with 0.1-10 000 ng/ml Oscillatoria sp. LPS resulted in minimal lactic dehydrogenase (LDH) release, induced concentration-dependent and statistically significant O2 (-) generation, matrix metalloproteinase-9 (MMP-9) release, generation of the cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and the chemokines macrophage inflammatory protein-2 (MIP-2/CXCL2), interferon γ-induced protein 10 kDa (IP-10/CXCL-10), (MIP-1α/CCL3), monocyte chemotactic protein-1 (MCP-1/CCL2), regulated on activation, normal T cell expressed and secreted (RANTES/CCL5), and the alternative activation cytokine IL-10; (3) in contrast, treatment with 100 000 ng/ml Oscillatoria sp. LPS appeared to damage the microglia cell membrane, because it resulted in minimal O2 (-) generation, statistically significant LDH release, and a decrease in the generation of all the cytokines and chemokines investigated, with the exception of IL-1α and cytokine-induced neutrophil chemoattractant 1 (CINC-1/CXCL1) generation, which was increased. Thus, our results provide experimental support for our working hypothesis, namely that Oscillatoria sp. LPS induces classical and alternative activation of rat brain microglia in vitro in a concentration-dependent manner, namely 0.1-10 000 ng/ml Oscillatoria sp. LPS, when microglia cells were shown to be viable. Furthermore, should cyanobacterium Oscillatoria sp. LPS gain entry into the CNS, our findings suggest that classical and alternative activation of rat brain microglia in vivo, might lead to concomitant mediator release that could result in an interplay between neuroinflammation and neural repair in a concentration-dependent manner.
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Affiliation(s)
| | - Joseph Murphy
- Biomedical Sciences Program, College of Health Sciences, Midwestern University, Downers Grove, Illinois 60515; and
| | - David MacAdam
- Biomedical Sciences Program, College of Health Sciences, Midwestern University, Downers Grove, Illinois 60515; and
| | - Christopher Osterbauer
- Biomedical Sciences Program, College of Health Sciences, Midwestern University, Downers Grove, Illinois 60515; and
| | - Imaan Baseer
- Biomedical Sciences Program, College of Health Sciences, Midwestern University, Downers Grove, Illinois 60515; and
| | - Mary L Hall
- *Department of Pharmacology, Chicago College of Osteopathic Medicine and
| | - Domonkos Feher
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96882
| | - Phillip Williams
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96882
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Koreivienė J, Anne O, Kasperovičienė J, Burškytė V. Cyanotoxin management and human health risk mitigation in recreational waters. ENVIRONMENTAL MONITORING AND ASSESSMENT 2014; 186:4443-4459. [PMID: 24664523 DOI: 10.1007/s10661-014-3710-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 03/05/2014] [Indexed: 06/03/2023]
Abstract
The occurrence and severity of harmful cyanobacterial or blue-green algal blooms (HABs) have increased in recent decades, posing a serious threat of illness to humans. In some countries, water contaminated with cyanotoxins that is used for drinking or haemodialysis has posed a particularly serious risk. However, it is now recognized that recreational exposure to natural toxins by skin contact, accidental swallowing of water or inhalation can also cause a wide range of acute or chronic illnesses. In this review, we focus on the importance of cyanotoxin management in recreational waters. The symptoms related with HAB poisonings, the recommended safety concentrations limit for cyanobacteria and cyanotoxins in such waters, as well as early health hazard indicators of their presence and their monitoring are all discussed. We also present in this review an overview of the methods developed in recent decades for eliminating cyanobacteria and the toxic compounds that they produce.
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Affiliation(s)
- Judita Koreivienė
- Institute of Botany of Nature Research Centre, Žaliųjų Ežerų Str. 49, 08406, Vilnius, Lithuania,
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Lu X, Tian C, Pei H, Hu W, Xie J. Environmental factors influencing cyanobacteria community structure in Dongping Lake, China. J Environ Sci (China) 2013; 25:2196-2206. [PMID: 24552047 DOI: 10.1016/s1001-0742(12)60297-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The present study was conducted to provide a detailed understanding of the variation in cyanobacterial communities of Dongping Lake, which is the final water volume adjusting and storing lake in the east route of the South-to-North Water Diversion Project in China. The spatial and temporal distribution of cyanobacteria was assessed from May 2010 to October 2012 based on monthly samples collected from three stations. Over the 30-month survey, 15 genera and 25 species of cyanobacteria were identified, with cyanobacterial abundance at each monitoring station ranging from undetected to 3.04x10(7) cells/L, average of 4.27x10(6) cells/L. The dominant cyanobacterial species were Pseudanabaena limnetica and Aphanizomenon issatschenkoi and not the usual bloom-forming genera such as Microcystis and Anabaena. Cyanobacterial community structure and water quality variables exhibited substantial changes over the period of survey. Redundancy analysis, Pearson correlations, and regression analysis were applied to analyze the relationships among the variables. The results suggested that temperature and chemical oxygen demand were key drivers of the cyanobacterial community composition in Dongping Lake. In addition, the concentration of inorganic nitrogen in the lake had a profound effect on the cyanobacterial abundance as a non-limiting factor in warm periods.
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Affiliation(s)
- Xuetang Lu
- School of Environmental Science and Engineering, Shandong University, Jinan 250061, China.
| | - Chang Tian
- School of Environmental Science and Engineering, Shandong University, Jinan 250061, China
| | - Haiyan Pei
- Shandong Provincial Engineering Center on Environmental Science and Technology, Jinan 250061, China
| | - Wenrong Hu
- School of Environmental Science and Engineering, Shandong University, Jinan 250061, China
| | - Jun Xie
- Shandong Environmental Monitoring Central Station, Jinan 250013, China
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Carillo S, Pieretti G, Bedini E, Parrilli M, Lanzetta R, Corsaro MM. Structural investigation of the antagonist LPS from the cyanobacterium Oscillatoria planktothrix FP1. Carbohydr Res 2013; 388:73-80. [PMID: 24632212 DOI: 10.1016/j.carres.2013.10.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 09/18/2013] [Accepted: 10/14/2013] [Indexed: 12/26/2022]
Abstract
Cyanobacteria are aquatic and photosynthetic microorganisms, which contribute up to 30% of the yearly oxygen production on the earth. They have the distinction of being the oldest known fossils, more than 3.5 billion years old, and are one of the largest and most important groups of bacteria on earth. Cyanobacteria are an emerging source of potentially pharmacologically active products and, among these, there are the lipopolysaccharides. Despite their significant and well documented activity, very little is known about the cyanobacteria lipopolysaccharides (LPS) structure. The aim of this work is to investigate the structure of the highly TLR4-antagonist lipopolysaccharide from the cyanobacterium Oscillatoria plankthotrix FP1. The LPS was purified and analysed by means of chemical analysis and 1H and 13C NMR spectroscopy. The LPS was then degraded by Smith degradation, HF and acetic acid hydrolyses. All the obtained products were investigated in detail by chemical analysis, NMR spectroscopy and by mass spectrometry. The LPS consists of a high molecular mass and very complex molecule lacking Kdo and heptose residues, where the polysaccharide chain is mainly constituted by a backbone of 3-substituted α-l-rhamnose units. The core region is rich in galacturonic acid and mannose residues. Moreover a glycolipid portion, similar to Gram-negative lipid A, was identified. This was built up of a non phosphorylated (1'→6) linked glucosamine disaccharide, acylated with 3-hydroxylated fatty acids. In particular 3-hydroxypentadecanoic and 3-hydroxyesadecanoic acids were found, together with esadecanoic and tetradecanoic ones. Finally the presence of a galacturonic acid residue at 6-position of the distal glucosamine in place of the Kdo residue is suggested.
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Affiliation(s)
- Sara Carillo
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di Monte S.Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Giuseppina Pieretti
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di Monte S.Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Emiliano Bedini
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di Monte S.Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Michelangelo Parrilli
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di Monte S.Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Rosa Lanzetta
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di Monte S.Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Maria Michela Corsaro
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario di Monte S.Angelo, Via Cintia 4, 80126 Napoli, Italy.
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9
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Gutierrez DB, Rafalski A, Beauchesne K, Moeller PD, Triemer RE, Zimba PV. Quantitative mass spectrometric analysis and post-extraction stability assessment of the euglenoid toxin euglenophycin. Toxins (Basel) 2013; 5:1587-96. [PMID: 24051554 PMCID: PMC3798875 DOI: 10.3390/toxins5091587] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 09/05/2013] [Accepted: 09/06/2013] [Indexed: 11/16/2022] Open
Abstract
Euglenophycin is a recently discovered toxin produced by at least one species of euglenoid algae. The toxin has been responsible for several fish mortality events. To facilitate the identification and monitoring of euglenophycin in freshwater ponds, we have developed a specific mass spectrometric method for the identification and quantitation of euglenophycin. The post-extraction stability of the toxin was assessed under various conditions. Euglenophycin was most stable at room temperature. At 8 °C there was a small, but statistically significant, loss in toxin after one day. These methods and knowledge of the toxin's stability will facilitate identification of the toxin as a causative agent in fish kills and determination of the toxin's distribution in the organs of exposed fish.
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Affiliation(s)
- Danielle B. Gutierrez
- Center for Coastal Studies Texas A&M University Corpus Christi 6300 Ocean Drive Corpus Christi, TX 78412, USA; E-Mail:
| | - Alexandra Rafalski
- Fisheries and Wildlife, Michigan State University, East Lansing, MI 48824, USA; E-Mail:
| | - Kevin Beauchesne
- NOAA/NCCOS Center for Human Health Research Hollings Marine Laboratory, 331 Fort Johnson Rd, Charleston, SC 29412, USA; E-Mails: (K.B.); (P.D.M.)
| | - Peter D. Moeller
- NOAA/NCCOS Center for Human Health Research Hollings Marine Laboratory, 331 Fort Johnson Rd, Charleston, SC 29412, USA; E-Mails: (K.B.); (P.D.M.)
| | - Richard E. Triemer
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA; E-Mail:
| | - Paul V. Zimba
- Center for Coastal Studies Texas A&M University Corpus Christi 6300 Ocean Drive Corpus Christi, TX 78412, USA; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel: +1-361-825-2768; Fax: +1-361-825-2770
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First report of a toxic Nodularia spumigena (Nostocales/ Cyanobacteria) bloom in sub-tropical Australia. I. Phycological and public health investigations. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2012; 9:2396-411. [PMID: 22851951 PMCID: PMC3407912 DOI: 10.3390/ijerph9072396] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 06/12/2012] [Accepted: 06/27/2012] [Indexed: 11/17/2022]
Abstract
Cyanobacterial blooms represent one of the most conspicuous and widespread waterborne microbial hazards to human and ecosystem health. Investigation of a cyanobacterial bloom in a shallow brackish water recreational cable ski lake in south-eastern Queensland, Australia revealed the dominance of the toxigenic species Nodularia spumigena. The bloom spanned three months, during which time cell concentrations exceeded human guideline thresholds for recreational risk, and concentrations of the hepatotoxic cyanotoxin nodularin exceeded 200 µg L(-1). Cyanotoxin origin and identification was confirmed by amplification of the ndaF-specific PCR product and sequencing of the 16S rRNA gene. From the limited data available leading up to, and throughout the bloom, it was not possible to establish the set of causative factors responsible for its occurrence. However a combination of factors including salinity, hydraulic retention time and nutrient status associated with an extended period of drought are likely to have contributed. This was the first known occurrence of this species in bloom proportions from sub-tropical Australia and as such represents a hitherto uncharacterized risk to human and ecosystem health. It highlights the need for adaptive monitoring regimes to ensure a comprehensive understanding of the potentially toxic cyanobacteria likely to inhabit any given region. Such monitoring needs to recognize that cyanobacteria have a significant capacity for range expansion that has been facilitated by recent changes in global climate.
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Mayer AMS, Clifford JA, Aldulescu M, Frenkel JA, Holland MA, Hall ML, Glaser KB, Berry J. Cyanobacterial Microcystis aeruginosa lipopolysaccharide elicits release of superoxide anion, thromboxane B₂, cytokines, chemokines, and matrix metalloproteinase-9 by rat microglia. Toxicol Sci 2011; 121:63-72. [PMID: 21362633 DOI: 10.1093/toxsci/kfr045] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Microcystis aeruginosa (M. aeruginosa) is a cosmopolitan Gram-negative cyanobacterium that may contaminate freshwater by releasing toxins, such as lipopolysaccharide (LPS) during aquatic blooms, affecting environmental and human health. The putative toxic effects of cyanobacterial LPS on brain microglia, a glial cell type that constitutes the main leukocyte-dependent source of reactive oxygen species in the central nervous system, are presently unknown. We tested the hypothesis that in vitro concentration- and time-dependent exposure to M. aeruginosa LPS strain UTCC 299 would activate rat microglia and the concomitant generation of superoxide anion (O₂⁻). After a 17-h exposure of microglia to M.aeruginosa LPS, the following concentration-dependent responses were observed: 0.1-100 ng/ml M. aeruginosa LPS enhanced O₂⁻ generation, with limited inflammatory mediator generation; 1000-10,000 ng/ml M. aeruginosa LPS caused thromboxane B₂ (TXB₂), matrix metalloproteinase-9 (MMP-9), and macrophage inflammatory protein-2 (MIP-2/CXCL2) release, concurrent with maximal O₂⁻ generation; 100,000 ng/mL M. aeruginosa LPS deactivated O₂⁻ production but maintained elevated levels of TXB₂, MMP-9, tumor necrosis factor-α (TNF-α), interleukin 1-α (IL-1α), and interleukin-6 (IL-6), macrophage inflammatory protein 1α (MIP-1α/CCL3), and MIP-2/CXCL2, with concomitant lactic dehydrogenase release. Although M. aeruginosa LPS was consistently less potent than Escherichia coli LPS, with the exception of O₂⁻, TXB₂, and MCP-1/CCL2 generation, it was more efficacious because higher levels of MMP-9, TNF-α, IL-1α, IL-6, MIP-1α/CCL3, and MIP-2/CXCL2 were produced. Our in vitro studies suggest that one or more of the inflammatory mediators released during M. aeruginosa LPS stimulation of microglia may play a critical role in the subsequent ability of microglia to generate O₂⁻. To our knowledge, this is the first experimental evidence that LPS isolated from a M. aeruginosa strain, can activate brain microglia in vitro, as well as the release of O₂⁻, and other inflammatory mediators hypothesized to be involved in neuroinflammation and neurodegeneration.
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Affiliation(s)
- Alejandro M S Mayer
- Department of Pharmacology, Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, Illinois 60515, USA.
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