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Li H, Jiang M, Li P, Xu Z, Jiang P, Chen L, Gin KYH, He Y. Picocyanobacterial-bacterial interactions sustain cyanobacterial blooms in nutrient-limited aquatic environments. ENVIRONMENTAL RESEARCH 2024; 260:119508. [PMID: 38945511 DOI: 10.1016/j.envres.2024.119508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 06/25/2024] [Accepted: 06/27/2024] [Indexed: 07/02/2024]
Abstract
Cyanobacterial blooms (CBs) and concomitant water quality issues in oligotrophic/mesotrophic waters have been recently reported, challenging the conventional understanding that CBs are primarily caused by eutrophication. To elucidate the underlying mechanism of CBs in nutrition-deficient waters, the changes in Chlorophyll a (Chl-a), cyanobacterial-bacterial community composition, and certain microbial function in Qingcaosha Reservoir, the global largest tidal estuary storage reservoir, were analyzed systematically and comprehensively after its pilot run (2011-2019) in this study. Although the water quality was improved and stabilized, more frequent occurrences of bloom level of Chl-a (>20 μg L-1) in warm seasons were observed during recent years. The meteorological changes (CO2, sunshine duration, radiation, precipitation, evaporation, and relative humidity), water quality variations (pH, total organic carbon content, dissolved oxygen, and turbidity), accumulated sediments as an endogenous source, as well as unique estuarine conditions collectively facilitated picocyanobacterial-bacterial coexistence and community functional changes in this reservoir. A stable and tight co-occurrence pattern was established between dominant cyanobacteria (Synechococcus, Cyanobium, Planktothrix, Chroococcidiopsis, and Prochlorothrix) and certain heterotrophic bacteria (Proteobacteria, Actinobacteria, and Bacteroidetes), which contributed to the remineralization of organic matter for cyanobacteria utilization. The relative abundance of chemoorganoheterotrophs and bacteria related to nitrogen transformation (Paracoccus, Rhodoplanes, Nitrosomonas, and Zoogloea) increased, promoting the emergence of CBs in nutrient-limited conditions through enhanced nutrient recycling. In environments with limited nutrients, the interaction between photosynthetic autotrophic microorganisms and heterotrophic bacteria appears to be non-competitive. Instead, they adopt complementary roles within their ecological niche over long-term succession, mutually benefiting from this association. This long-term study confirmed that enhanced nutrient cycling, facilitated by cyanobacterial-bacterial symbiosis following long-term succession, could promote CBs in oligotrophic aquatic environments devoid of external nutrient inputs. This study advances understanding of the mechanisms that trigger and sustain CBs under nutritional constraints, contributing to developing more effective mitigation strategies, ensuring water safety, and maintaining ecological balance.
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Affiliation(s)
- Huimin Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, PR China
| | - Mengqi Jiang
- Center for Ecological Research, Kyoto University, Shiga, 520-2113, Japan
| | - Peng Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, PR China
| | - Zheng Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, PR China
| | - Peng Jiang
- Department of Industrial Engineering and Management, Sichuan University, Chengdu, 610064, PR China
| | - Lei Chen
- Shanghai National Engineering Research Center of Urban Water Resources Co., Ltd., Shanghai, 200082, PR China
| | - Karina Yew-Hoong Gin
- National University of Singapore Environmental Research Institute, National University of Singapore, 1 Create Way, #15-02, Singapore, 138602, Singapore
| | - Yiliang He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, PR China.
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Falfushynska H, Kasianchuk N, Siemens E, Henao E, Rzymski P. A Review of Common Cyanotoxins and Their Effects on Fish. TOXICS 2023; 11:toxics11020118. [PMID: 36850993 PMCID: PMC9961407 DOI: 10.3390/toxics11020118] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/23/2023] [Accepted: 01/23/2023] [Indexed: 05/31/2023]
Abstract
Global warming and human-induced eutrophication drive the occurrence of various cyanotoxins in aquatic environments. These metabolites reveal diversified mechanisms of action, encompassing cyto-, neuro-, hepato-, nephro-, and neurotoxicity, and pose a threat to aquatic biota and human health. In the present paper, we review data on the occurrence of the most studied cyanotoxins, microcystins, nodularins, cylindrospermopsin, anatoxins, and saxitoxins, in the aquatic environment, as well as their potential bioaccumulation and toxicity in fish. Microcystins are the most studied among all known cyanotoxins, although other toxic cyanobacterial metabolites are also commonly identified in aquatic environments and can reveal high toxicity in fish. Except for primary toxicity signs, cyanotoxins adversely affect the antioxidant system and anti-/pro-oxidant balance. Cyanotoxins also negatively impact the mitochondrial and endoplasmic reticulum by increasing intracellular reactive oxygen species. Furthermore, fish exposed to microcystins and cylindrospermopsin exhibit various immunomodulatory, inflammatory, and endocrine responses. Even though cyanotoxins exert a complex pressure on fish, numerous aspects are yet to be the subject of in-depth investigation. Metabolites other than microcystins should be studied more thoroughly to understand the long-term effects in fish and provide a robust background for monitoring and management actions.
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Affiliation(s)
- Halina Falfushynska
- Department of Marine Biology, Institute for Biological Sciences, University of Rostock, 18059 Rostock, Germany
- Faculty of Electrical, Mechanical and Industrial Engineering, Anhalt University for Applied Sciences, 06366 Köthen, Germany
| | - Nadiia Kasianchuk
- Faculty of Biology, Adam Mickiewicz University, 61712 Poznan, Poland
| | - Eduard Siemens
- Faculty of Electrical, Mechanical and Industrial Engineering, Anhalt University for Applied Sciences, 06366 Köthen, Germany
| | - Eliana Henao
- Research Group Integrated Management of Ecosystems and Biodiversity XIUÂ, School of Biological Sciences, Universidad Pedagógica y Tecnológica de Colombia, Tunja 150003, Colombia
| | - Piotr Rzymski
- Department of Environmental Medicine, Poznan University of Medical Sciences, 61701 Poznan, Poland
- Integrated Science Association (ISA), Universal Scientific Education and Research Network (USERN), 61701 Poznań, Poland
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Wilk-Woźniak E, Szarek-Gwiazda E, Walusiak E, Kosiba J, Krztoń W. Non-Nitrogen-Fixers or Nitrogen-Fixers? Factors Distinguishing the Dominance of Chroococcal and Diazotrophic Cyanobacterial Species. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:15980. [PMID: 36498050 PMCID: PMC9738033 DOI: 10.3390/ijerph192315980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/27/2022] [Accepted: 11/27/2022] [Indexed: 06/17/2023]
Abstract
Global warming and eutrophication are the main factors driving the development of cyanobacterial dominance in aquatic ecosystems. We used a model linking water temperature, oxygen saturation, concentrations of PO43-, NO3-, NH4+, total dissolved iron (TDFe), and SO42- to cyanobacteria to test the turnover patterns of cyanobacterial dominance of non-nitrogen-fixing (chroococcal species) and nitrogen-fixing (filamentous diazotrophic) species. Statistical analysis was performed using decision trees. The dominance patterns of the two morphologically and ecologically distinct cyanobacterial species were associated with different environmental factors. However, SO42- was the most important factor that explained whether non-nitrogen-fixing or nitrogen-fixing species would dominate. Other important factors were water temperature, phosphate concentration, and oxygen saturation. The model for dominance of non-nitrogen-fixing species used SO42-, PO43-, and water temperature (upper layers), and SO42-, the ratio of PO43-/NH4+, and oxygen saturation (bottom layers). In contrast, water temperature, SO42-, and NH4+ in the upper layers and SO42-, NH4+, and water temperature in the bottom layers were used for the dominance of nitrogen-fixing species. The dominance of Aphanizomenon flos-aquae was explained by different sets of variables, indicating the presence of different strains of this species. The other cyanobacteria species showed dominance patterns that could be explained by one set of variables. As cyanobacterial blooms proliferate due to climate change, it is important to know which factors, in addition to phosphorus and nitrogen, are crucial for the mass development of the various cyanobacterial species.
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Lenard T, Poniewozik M. Planktothrix agardhii versus Planktothrix rubescens: Separation of Ecological Niches and Consequences of Cyanobacterial Dominance in Freshwater. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:14897. [PMID: 36429622 PMCID: PMC9690196 DOI: 10.3390/ijerph192214897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/03/2022] [Accepted: 11/09/2022] [Indexed: 06/16/2023]
Abstract
Cyanobacteria dominate lakes under diverse trophic conditions. Of these, two harmful filamentous cyanobacterial species, namely Planktothrix agardhii and P. rubescens, occupy completely different ecological niches in which they can form dense populations. In the present study, we investigated the effects of environmental conditions on the growth and vertical distribution of these species in lakes of different trophic statuses. Moreover, we underscored certain inconveniences in the assessment of the ecological status of lakes according to the European Union Water Framework Directive. The highest biomass of P. agardhii was recorded in eutrophic lake at a depth of 0.5-1 m, under high light intensity. Meanwhile, the highest biomass of P. rubescens, at which the deep chlorophyll maximum was recorded, was observed in mesotrophic lakes at a depth of 11-12 m, often below the euphotic zone under very low light intensity. P. rubescens, but not P. agardhii, exerted a strong allelopathic effect on the diversity and biomass of phytoplankton. Moreover, both species utilised different dissolved nitrogen fractions for their growth; specifically, P. agardhii used ammonium nitrogen, whilst P. rubescens used nitrate nitrogen. Furthermore, dissolved phosphorus produced a potentially limiting effect on P. rubescens growth. Overall, the tested Polish PMPL, German PSI, and Estonian phytoplankton indices were indeed useful in the assessment of the ecological status of lakes, albeit limited to the eutrophic lake with a high biomass of cyanobacteria (P. agardhii) in the upper water layers. However, problems arose in the proper assessment of lakes with a high biomass of cyanobacteria (P. rubescens) with a deep chlorophyll maximum outside the range of the euphotic zone. In such cases, two of the tested indices, namely the Polish and German indices, allowed sample collection from the euphotic layers, which significantly affected the number of samples included in the calculation. Consequently, the correct calculation of the ecological status of the lake was uncertain. Only the Estonian index allowed for a sample collection from two to three thermal layers of water, including the bloom layer of P. rubescens. Hence, the Estonian index offered the best fit for calculations.
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Affiliation(s)
- Tomasz Lenard
- Department of Animal Physiology and Toxicology, Faculty of Medicine, The John Paul II Catholic University of Lublin, Konstantynów 1I, PL-20-708 Lublin, Poland
| | - Małgorzata Poniewozik
- Department of Plant Physiology and Biotechnology, Faculty of Medicine, The John Paul II Catholic University of Lublin, Konstantynów 1I, PL-20-708 Lublin, Poland
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Chen J, Liu H, Bai Y, Qi J, Qi W, Liu H, Peng J, Qu J. Mixing regime shapes the community assembly process, microbial interaction and proliferation of cyanobacterial species Planktothrix in a stratified lake. J Environ Sci (China) 2022; 115:103-113. [PMID: 34969441 DOI: 10.1016/j.jes.2021.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 07/04/2021] [Accepted: 07/05/2021] [Indexed: 06/14/2023]
Abstract
Lake mixing influences aquatic chemical properties and microbial community composition, and thus, we hypothesized that it would alter microbial community assembly and interaction. To clarify this issue, we explored the community assembly processes and cooccurrence networks in four seasons at two depths (epilimnion and hypolimnion) in a mesotrophic and stratified lake (Chenghai Lake), which formed stratification in the summer and turnover in the winter. During the stratification period, the epilimnion and hypolimnion went through contrary assembly processes but converged to similar assembly patterns in the mixing period. In a highly homogeneous selection environment, species with low niche breadth were filtered, resulting in decreased species richness. Water mixing in the winter homogenized the environment, resulting in a simpler microbial cooccurrence network. Interestingly, we observed a high abundance of the cyanobacterial genus Planktothrix in the winter, probably due to nutrient redistribution and Planktothrix adaptivity to the winter environment in which mixing played important roles. Our study provides deeper fundamental insights into how environmental factors influence microbial community structure through community assembly processes.
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Affiliation(s)
- Junwen Chen
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Huacong Liu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yaohui Bai
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Jing Qi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Weixiao Qi
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Huijuan Liu
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Jianfeng Peng
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Jiuhui Qu
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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Research Characteristics on Cyanotoxins in Inland Water: Insights from Bibliometrics. WATER 2022. [DOI: 10.3390/w14040667] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Eutrophication is a long-standing ecological and environmental problem, and the severity of harmful algal blooms continues to increase, causing large economic losses globally. One of the most important hazards created by harmful algal blooms is the production of cyanotoxins. This study aimed to analyze the characteristics and development trends of cyanotoxin research through bibliometric analysis. A total of 3265 publications from 1990 to 2020 on cyanotoxins were retrieved from the Science Citation Index (SCI) Expanded database, Web of Science. Over the past 30 years, most research has been concentrated in China (21.4%) and the USA (21.3%). Throughout the study period, microcystin was the focus of the research, accounting for 86% of the total number of publications. A word frequency analysis revealed that as people became more aware of drinking water safety and the construction of large-scale water conservation facilities, “reservoirs” and “rivers” became hot words for researchers, while “lakes” have always been important research objects. Nonmetric multidimensional scaling (NMDS) analysis of studies from the five countries with the largest numbers of publications showed that Chinese researchers typically associate eutrophication with Microcystis, while research subjects in other countries are more extensive and balanced. The development of cyanotoxin research around the world is not even, and we need to push for more research on major lakes that are outside of North America, Europe and China.
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León C, Úsuga O, Peñuela G. Statistical model applied in the qualitative and quantitative analysis of the relationships between environmental variables and cyanotoxin concentrations in tropical reservoirs. ENVIRONMENTAL MONITORING AND ASSESSMENT 2022; 194:147. [PMID: 35122535 DOI: 10.1007/s10661-021-09739-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 12/23/2021] [Indexed: 06/14/2023]
Abstract
This article presents the use of generalized additive model for location scale and shape (GAMLSS) in the qualitative and quantitative analysis of the relationships between environmental parameters and cyanotoxins in the tropical reservoirs of Colombia. The physicochemical parameters were evaluated on each of the cyanotoxins detected with levels high by ultra-high-performance liquid chromatography coupled to triple quadrupole mass spectrometry. The models showed a relation between cyanotoxins and the nutrients as soluble total Kjeldahl nitrogen (NTK), soluble phosphorus (soluble P), total phosphorus (total P), and nitrates (NO3-), among other nutrients that are necessary for the growth of organisms that produce toxins. This model confirms that the NTK and soluble P variables favor an increase in the concentration of MC-LR and MC-YR cyanotoxins in the Abreo Malpaso reservoir. The variables NO3- and dissolved O2 contribute to a higher concentration of MC-LR, MC-YR, and MC-ADRR cyanotoxins in the Peñol reservoir. Finally, the variable total P favors the increase in the concentration of MC-LR cyanotoxin and the variable dissolved O2 favors the increase in the concentration of cyanotoxin [D-Asp3, (E)-Dhb7] -MC-RR in the Playas reservoir.
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Affiliation(s)
- Cristina León
- Grupo GDCON, Facultad de Ingeniería, Sede de Investigación Universitaria (SIU), Universidad de Antioquia, 53 # 61-30, Medellin, Colombia
| | - Olga Úsuga
- Grupo INCAS, Facultad de Ingeniería, Universidad de Antioquia, 70 # 52-21, Medellin, Colombia
| | - Gustavo Peñuela
- Grupo GDCON, Facultad de Ingeniería, Sede de Investigación Universitaria (SIU), Universidad de Antioquia, 53 # 61-30, Medellin, Colombia.
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Tanvir RU, Hu Z, Zhang Y, Lu J. Cyanobacterial community succession and associated cyanotoxin production in hypereutrophic and eutrophic freshwaters. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 290:118056. [PMID: 34488165 PMCID: PMC8547520 DOI: 10.1016/j.envpol.2021.118056] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 08/01/2021] [Accepted: 08/24/2021] [Indexed: 05/06/2023]
Abstract
Cyanobacterial harmful algal blooms (cyanoHABs) in freshwater bodies are mainly attributed to excess loading of nutrients [nitrogen (N) and phosphorus (P)]. This study provides a comprehensive review of how the existing nutrient (i.e., N and P) conditions and microbial ecological factors affect cyanobacterial community succession and cyanotoxin production in freshwaters. Different eutrophic scenarios (i.e., hypereutrophic vs. eutrophic conditions) in the presence of (i) high levels of N and P, (ii) a relatively high level of P but a low level of N, and (iii) a relatively high level of N but a low level of P, are discussed in association with cyanobacterial community succession and cyanotoxin production. The seasonal cyanobacterial community succession is mostly regulated by temperature in hypereutrophic freshwaters, where both temperature and nitrogen fixation play a critical role in eutrophic freshwaters. While the early cyanoHAB mitigation strategies focus on reducing P from water bodies, many more studies show that both N and P have a profound contribution to cyanobacterial blooms and toxin production. The availability of N often shapes the structure of the cyanobacterial community (e.g., the relative abundance of N2-fixing and non-N2-fixing cyanobacterial genera) and is positively linked to the levels of microcystin. Ecological aspects of cyanotoxin production and release, related functional genes, and corresponding nutrient and environmental conditions are also elucidated. Research perspectives on cyanoHABs and cyanobacterial community succession are discussed and presented with respect to the following: (i) role of internal nutrients and their species, (ii) P- and N-based control vs. solely P-based control of cyanoHABs, and (iii) molecular investigations and prediction of cyanotoxin production.
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Affiliation(s)
- Rahamat Ullah Tanvir
- Department of Civil and Environmental Engineering, University of Missouri, Columbia, MO, 65211, USA
| | - Zhiqiang Hu
- Department of Civil and Environmental Engineering, University of Missouri, Columbia, MO, 65211, USA
| | - Yanyan Zhang
- Department of Civil Engineering, New Mexico State University, Las Cruces, NM, 88003, USA
| | - Jingrang Lu
- Office of Research and Development, United States Environmental Protection Agency (USEPA), Cincinnati, OH, 45268, USA.
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Phytoplankton of the Curonian Lagoon as a New Interesting Source for Bioactive Natural Products. Special Impact on Cyanobacterial Metabolites. Biomolecules 2021; 11:biom11081139. [PMID: 34439804 PMCID: PMC8395022 DOI: 10.3390/biom11081139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/26/2021] [Accepted: 07/29/2021] [Indexed: 12/21/2022] Open
Abstract
The bioprospecting of marine and brackish water systems has increased during the last decades. In this respect, microalgae, including cyanobacteria, and their metabolites are one of the most widely explored resources. Most of the bioactive compounds are isolated from ex situ cultures of microorganisms; however, analysis of field samples could also supply valuable information about the metabolic and biotechnological potential of microalgae communities. In this work, the activity of phytoplankton samples from the Curonian Lagoon was studied. The samples were active against antibiotic resistant clinical and environmental bacterial strains as well as against serine proteases and T47D human breast adenocarcinoma cells. No significant effect was found on Daphnia magna. In addition, using LC-MS/MS, we documented the diversity of metabolites present in field samples. A list of 117 detected cyanopeptides was presented. Cyanopeptolins constituted the largest class of cyanopeptides. As complex bloom samples were analyzed, no link between the observed activity and a specific sample component can be established. However, the results of the study showed a biotechnological potential of natural products from the Curonian Lagoon.
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Algal Toxic Compounds and Their Aeroterrestrial, Airborne and other Extremophilic Producers with Attention to Soil and Plant Contamination: A Review. Toxins (Basel) 2021; 13:toxins13050322. [PMID: 33946968 PMCID: PMC8145420 DOI: 10.3390/toxins13050322] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 04/27/2021] [Accepted: 04/27/2021] [Indexed: 12/16/2022] Open
Abstract
The review summarizes the available knowledge on toxins and their producers from rather disparate algal assemblages of aeroterrestrial, airborne and other versatile extreme environments (hot springs, deserts, ice, snow, caves, etc.) and on phycotoxins as contaminants of emergent concern in soil and plants. There is a growing body of evidence that algal toxins and their producers occur in all general types of extreme habitats, and cyanobacteria/cyanoprokaryotes dominate in most of them. Altogether, 55 toxigenic algal genera (47 cyanoprokaryotes) were enlisted, and our analysis showed that besides the “standard” toxins, routinely known from different waterbodies (microcystins, nodularins, anatoxins, saxitoxins, cylindrospermopsins, BMAA, etc.), they can produce some specific toxic compounds. Whether the toxic biomolecules are related with the harsh conditions on which algae have to thrive and what is their functional role may be answered by future studies. Therefore, we outline the gaps in knowledge and provide ideas for further research, considering, from one side, the health risk from phycotoxins on the background of the global warming and eutrophication and, from the other side, the current surge of interest which phycotoxins provoke due to their potential as novel compounds in medicine, pharmacy, cosmetics, bioremediation, agriculture and all aspects of biotechnological implications in human life.
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