Daphnia magna tolerance to toxic cyanobacteria in the presence of an opportunistic infection within an evolutionary perspective

In aquatic environments, interactions between cyanobacteria and their grazers are crucial for ecosystem functioning. Cyanobacteria are photosynthetic prokaryotes, which are able to produce large blooms and associated toxins, some of which are able to suppress grazer fitness. Cyanobacterial blooms are intensified by global warming and eutrophication. In our experiments, the tolerance of Daphnia magna (Straus, 1820), an efficient grazer of toxic cyanobacteria, was studied. We used different D. magna clones sampled from different sediment depths, which corresponded to different time periods of eutrophication. Our results showed that different clones had a different tolerance towards the toxic cyanobacterial species, Microcystis aeruginosa, confirming the presence of genetic variation in D. magna tolerance to cyanobacteria. However, there was not a significant adaptive effect of sediment depth. As expected, in general under controlled, infection-free conditions M. aeruginosa reduced D. magna survival. However, a coincidental, non-intended opportunistic fungal infection in a first experiment allowed us to compare the response of D. magna to M. aeruginosa in infected individuals and non-infected individuals (from a second experiment). In the presence of this opportunistic infection, there was no negative effect of M. aeruginosa in the D. magna clones, suggesting that exposure to the infection provided protection for Daphnia individuals towards Microcystis. Biotic interactions can thus be important in the interpretation of cyanobacterial effects in zooplankton grazers and in finding appropriate solutions to reduce the occurrence of cyanobacterial blooms.

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Changes in cyanobacterial density due to application of Artificial Floating Island model with macrophytes: an experimental case study in a tropical reservoir

Journal of Limnology ◽

10.4081/jlimnol.2020.1959 ◽

2020 ◽

Author(s):

Pedro Ramírez-García ◽

David Chicalote-Castillo

Keyword(s):

Water Quality ◽

Rainy Season ◽

Specific Effect ◽

Cyanobacterial Blooms ◽

Dominant Group ◽

Tropical Reservoir ◽

Floating Island ◽

Toxic Cyanobacteria ◽

Cyanobacterial Species ◽

Restoration Strategies

The Valle de Bravo (VB) reservoir is part of an important hydraulic system that provides about 40% of potable water to 21.5 million inhabitants of the Metropolitan Zone of Mexico City (Mexico). This reservoir shows deterioration in water quality due to its current eutrophic condition, which favors the recurring of cyanobacterial blooms. To date, there are no restoration strategies for this reservoir, so the use of eco-technologies such as Artificial Floating Islands (AFI) is proposed for the removal of nutrients and the improvement of water quality. Therefore, in this work AFIs have been implemented using two macrophytes (Phragmites australis (AFI-P) and Schoenoplectus sp. (AFI-S)) to evaluate the presence and distribution of potentially toxic cyanobacteria in relation to physicochemical variations at the AFI sites. The study was carried out over a period of 24 months (October 2016 -September 2018) divided into two cycles (C-I and C-II) with a dry and rainy season each. Cyanobacteria were the dominant group in the phytoplankton during all the study period. Nine potentially toxic cyanobacterial species were detected, with the predominance of Microcystis aeruginosa, Aphanizomenon yezoense, Pseudanabaena mucicola, Anabaena planctonica and Planktothrix agardhii. In this work, AFIs increased nitrates and had no effect on phosphates. Cyanobacteria were not reduced at AFI sites, however in rainy season in the second annual cycle (C-II) the concentrations of extracellular microcystins in the AFI-P and AFI-S were decreased while intracellular toxins were more strongly reduced only in the AFI-S. Each AFI had a specific effect on four out of five potentially toxic cyanobacteria. Thus, AFI-P promoted the increase of M. aeruginosa but reduced A. planctonica, while AFI-S promoted both A. yezoense and P. mucicola. The AFIs modified the dynamics among cyanobacteria particularly diazotrophic A. yezoense which was favored by nitrates and the other three species maintained their presence by the phosphates. M. aeruginosa, non-diazotrophic, responded to nitrates only in the absence of A. yezoense. Finally, in VB reservoir we found a mutually exclusive relationship between M. aeruginosa and A. yezoense likewise between A. planctonica and P. mucicola.

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Differential Effect of Hydroxen Peroxide οn Toxic Cyanobacteria of Hypertrophic Mediterranean Waterbodies

Sustainability ◽

10.3390/su14010123 ◽

2021 ◽

Vol 14 (1) ◽

pp. 123

Author(s):

Theodoti Papadimitriou ◽

Matina Katsiapi ◽

Natassa Stefanidou ◽

Aikaterini Paxinou ◽

Vasiliki Poulimenakou ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Resistance Mechanisms ◽

Cyanobacterial Blooms ◽

Cylindrospermopsis Raciborskii ◽

Rapid Decomposition ◽

Promising Tool ◽

Hydrogen Peroxide Treatment ◽

Toxic Cyanobacteria ◽

Cyanobacterial Species ◽

Harmful Cyanobacterial Blooms

Cyanobacterial blooms have been known since ancient times; however, they are currently increasing globally. Human and ecological health risks posed by harmful cyanobacterial blooms have been recorded around the world. These risks are mainly associated with their ability to affect the ecosystem chain by different mechanisms like the production of cyanotoxins, especially microcystins. Their expansion and their harmful effects have led many researchers to seek techniques and strategies to control them. Among them, hydrogen peroxide could be a promising tool against cyanobacteria and cyanotoxins and it is well-established as an environmentally friendly oxidizing agent because of its rapid decomposition into oxygen and water. The aim of the present study was to evaluate the effect of hydrogen peroxide on phytoplankton from two hypertrophic waterbodies in Greece. The effect of hydrogen peroxide on concentration of microcystins found in the waterbodies was also studied. Treatment with 4 mg/L hydrogen peroxide was applied to water samples originated from the waterbodies and Cyanobacterial composition and biomass, phycocyanin, chlorophyll-a, and intra-cellular and total microcystin concentrations were studied. Cyanobacterial biomass and phycocyanin was reduced significantly after the application of 4 mg/L hydrogen peroxide in water treatment experiments while chlorophytes and extra-cellular microcystin concentrations were increased. Raphidiopsis (Cylindrospermopsis) raciborskii was the most affected cyanobacterial species after treatment of the water of the Karla Reservoir in comparison to Aphanizomenon favaloroi, Planktolyngbya limnetica, and Chroococcus sp. Furthermore, Microcystis aeruginosa was more resistant to the treatment of Pamvotis lake water in comparison with Microcystis wesenbergii and Microcystis panniformis. Our study showed that hydrogen peroxide differentially impacts the members of the phytoplankton community, affecting, thus, its overall efficacy. Different effects of hydrogen peroxide treatment were observed among cyanobacerial genera as well as among cyanobacterial species of the same genus. Different effects could be the result of the different resistance mechanisms of each genus or species to hydrogen peroxide. Hydrogen peroxide could be used as a treatment for the mitigation of cyanobacterial blooms in a waterbody; however, the biotic and abiotic characteristics of the waterbody should be considered.

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A Brief Review of the Structure, Cytotoxicity, Synthesis, and Biodegradation of Microcystins

Water ◽

10.3390/w13162147 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2147

Author(s):

Anjali Krishnan ◽

Xiaozhen Mou

Keyword(s):

Health Hazard ◽

Aquatic Organisms ◽

Water Soluble ◽

Cyanobacterial Blooms ◽

Aquatic Environments ◽

Natural Environments ◽

Exposure Pathway ◽

Environmental Transformation ◽

Cyclic Heptapeptide ◽

Harmful Cyanobacterial Blooms

Harmful cyanobacterial blooms pose an environmental health hazard due to the release of water-soluble cyanotoxins. One of the most prevalent cyanotoxins in nature is microcystins (MCs), a class of cyclic heptapeptide hepatotoxins, and they are produced by several common cyanobacteria in aquatic environments. Once released from cyanobacterial cells, MCs are subjected to physical chemical and biological transformations in natural environments. MCs can also be taken up and accumulated in aquatic organisms and their grazers/predators and induce toxic effects in several organisms, including humans. This brief review aimed to summarize our current understanding on the chemical structure, exposure pathway, cytotoxicity, biosynthesis, and environmental transformation of microcystins.

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Aquatic Toxicity Comparison of Silver Nanoparticles and Silver Nanowires

BioMed Research International ◽

10.1155/2015/893049 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 17

Author(s):

Eun Kyung Sohn ◽

Seyed Ali Johari ◽

Tae Gyu Kim ◽

Jin Kwon Kim ◽

Ellen Kim ◽

...

Keyword(s):

Silver Nanoparticles ◽

Daphnia Magna ◽

Silver Nanowires ◽

Aquatic Toxicity ◽

Oryzias Latipes ◽

Aquatic Environments ◽

Silver Nanomaterials ◽

Raphidocelis Subcapitata ◽

Test Organisms ◽

Test Fish

To better understand the potential ecotoxicological impact of silver nanoparticles (AgNPs) and silver nanowires (AgNWs) released into freshwater environments, the toxicities of these nanomaterials were assessed and compared using Organization for Economic Cooperation and Development (OECD) test guidelines, including a “Daphniasp., acute immobilization test,” “Fish, acute toxicity test,” and “freshwater alga and cyanobacteria, growth inhibition test.” Based on the estimated median lethal/effective concentrations of AgNPs and AgNWs, the susceptibility to the nanomaterials was different among test organisms (daphnia > algae > fish), suggesting that the AgNPs are classified as “category acute 1” forDaphnia magna, “category acute 2” forOryzias latipes, and “category acute 1” forRaphidocelis subcapitata, while the AgNWs are classified as “category acute 1” forDaphnia magna, “category acute 2” forOryzias latipes, and “category acute 2” forRaphidocelis subcapitata, according to the GHS (Globally Harmonized System of Classification and Labelling of Chemicals). In conclusion, the present results suggest that more attention should be paid to prevent the accidental or intentional release of silver nanomaterials into freshwater aquatic environments.

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Cyanobacterial blooms in kaliski region water reservoirs and water quality parameters / Zakwity sinicowe w zbiornikach okolic Kalisza a wskaźniki jakości wody

Archives of Environmental Protection ◽

10.1515/aep-2015-0002 ◽

2015 ◽

Vol 41 (1) ◽

pp. 15-23 ◽

Cited By ~ 2

Author(s):

Dominik Szczukocki ◽

Radosław Dałkowski ◽

Barbara Krawczyk ◽

Renata Juszczak ◽

Luiza Kubisiak-Banaszkiewicz ◽

...

Keyword(s):

Light Exposure ◽

Quality Parameters ◽

Cyanobacterial Blooms ◽

Cyanobacterial Cell ◽

Chemical Parameters ◽

Water Reservoirs ◽

Nitrogen And Phosphorus ◽

Water Parameters ◽

Physico Chemical ◽

Cyanobacterial Species

Abstract Cyanobacterial blooms occur frequently in artificial lakes, especially in water reservoirs with small retention exposition to anthropopressure. The abundant occurrence of cyanobacteria is accompanied by danger of oxygen imbalance in the aquatic environment and the secretion of toxins that are possible threat to human health and life. Cyanobacterial cell growth depends on a number of physical (temperature, light exposure), chemical (pH, concentration of compounds containing nitrogen and phosphorus) and biological (the presence of other organisms) factors. This paper presents the results of the analysis of water from reservoirs located in southern Wielkopolska region (Pokrzywnica-Szałe, Gołuchów and Piaski-Szczygliczka). Some important physico-chemical parameters of water samples taken from investigated reservoirs as well as cyanotoxins concentration were determined. Furthermore, the cyanobacterial species were identified. There was also an attempt made to correlate the water parameters with the cyanobacteria development and cyanotoxins production. On the basis of the results obtained in the analyzed season, it can be concluded that water from Pokrzywnica and Gołuchów reservoirs was rich in nutrients, hence the intense cyanobacterial blooms and cyanotoxins in water were observed

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Occurrence and Significance of Toxic Cyanobacteria in Southern Africa

Water Science & Technology ◽

10.2166/wst.1991.0413 ◽

1991 ◽

Vol 23 (1-3) ◽

pp. 175-180 ◽

Cited By ~ 29

Author(s):

W. E. Scott

Keyword(s):

South Africa ◽

Southern Africa ◽

Single Species ◽

Practical Significance ◽

Toxic Species ◽

Toxic Cyanobacteria ◽

Cyanobacterial Species ◽

Wide Range ◽

Toxic Blooms ◽

Different Parts

A comprehensive list is provided of more than forty cyanobacterial species and genera reported to have toxic properties. In South Africa the majority of animal poisonings since 1927 have been caused by a single species Microcystis aeruginosa. Although other toxic species also occur in southern Africa, to date they have been of little practical significance. The widespread distribution of M. aeruginosa throughout southern Africa indicates a tremendous potential for toxic blooms to develop with increasing eutrophication. Using HPLC techniques up to six different toxin variants have been quantified in natural blooms of M. aeruginosa collected in different parts of South Africa. The amounts and proportions of the different toxins in the different samples varied over a wide range. Several additional unidentified toxins were detected.

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Advancing Knowledge on Cyanobacterial Blooms in Freshwaters

Water ◽

10.3390/w12092583 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2583

Author(s):

Elisabeth Vardaka ◽

Konstantinos Ar. Kormas

Keyword(s):

Water Quality ◽

Drinking Water ◽

Mathematical Modelling ◽

Ecological Status ◽

Toxin Production ◽

Cyanobacterial Blooms ◽

Special Issue ◽

Research Papers ◽

Cyanobacterial Species ◽

Water Quality Deterioration

Cyanobacterial blooms have become a frequent phenomenon in freshwaters worldwide; they are a widely known indicator of eutrophication and water quality deterioration. Information and knowledge contributing towards the evaluation of the ecological status of freshwaters, particularly since many are used for recreation, drinking water, and aquaculture, is valuable. This Special Issue, entitled “Advancing Knowledge on Cyanobacterial Blooms in Freshwaters”, includes 11 research papers that will focus on the use of complementary approaches, from the most recently developed molecular-based methods to more classical approaches and experimental and mathematical modelling regarding the factors (abiotic and/or biotic) that control the diversity of not only the key bloom-forming cyanobacterial species, but also their interactions with other biota, either in freshwater systems or their adjacent habitats, and their role in preventing and/or promoting cyanobacterial growth and toxin production.

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The biology of the limnephilid caddisfly Dicosmoecus gilvipes (Hagen) in Northern California and Oregon (USA) Streams

Zoosymposia ◽

10.11646/zoosymposia.5.1.34 ◽

2011 ◽

Vol 5 (1) ◽

pp. 413-419 ◽

Cited By ~ 1

Author(s):

Vincent H. Resh ◽

Morgan Hannaford ◽

John K. Jackson ◽

Gary A. Lamberti ◽

Patina K. Mendez

Keyword(s):

Aquatic Insects ◽

Sex Pheromones ◽

Model Organism ◽

Biotic Interactions ◽

Northern California ◽

Large Size ◽

Behavioral Studies ◽

Negative Effect ◽

Males And Females ◽

Dicosmoecus Gilvipes

The limnephilid caddisfly Dicosmoecus gilvipies (Hagen) occurs in many streams of northwestern United States and British Columbia. Because of the large size of the fully grown larva, its synchronous emergence pattern, and its frequent imitation by fly-fishing anglers, D. gilvipes is one of the best known North American aquatic insects. Egg masses are found at the bases of Carex sedges. Cases of early larval instars are made of organic material and detritus; 3rd and 4th instars incorporate pebbles into cases. The 5th-instar case is made entirely of mineral material. Larvae can travel up to 25 m per day, and are predominantly scraper-grazers. Fifth instars attach their cases to the underside of boulders in mid-summer and remain dormant until pupation in autumn. All northern California populations known are univoltine. Adult females use sex pheromones to attract males; most males come to trapped females in the 1st hour after sunset. In laboratory studies, males and females fly during the mate attraction period but generally not at other times. Males but not females exhibit circadian rhythms that govern flight periodicity. In enclosures to study biotic interactions, the density of D. gilvipes larvae has a negative effect on the densities of sessile grazers. This species has been widely used in trophic and behavioral studies conducted in the laboratory and field, and may be a model organism for ecological studies of caddisflies and other benthic macroinvertebrates.

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Grazing of the copepod Cyclops vicinus on toxic Microcystis aeruginosa: potential for controlling cyanobacterial blooms and transfer of toxins

Oceanological and Hydrobiological Studies ◽

10.1515/ohs-2018-0028 ◽

2018 ◽

Vol 47 (3) ◽

pp. 296-302 ◽

Cited By ~ 5

Author(s):

Zakaria A. Mohamed ◽

Asmaa A. Bakr ◽

Hamed A. Ghramh

Keyword(s):

Microcystis Aeruginosa ◽

Grazing Rate ◽

Cyanobacterial Blooms ◽

Feeding Experiments ◽

Cyclops Vicinus ◽

Ankistrodesmus Falcatus ◽

Toxic Cyanobacteria ◽

Study Laboratory ◽

Grazer Species

Abstract Grazing of zooplankton on phytoplankton may contribute to a reduction of harmful cyanobacteria in eutrophic waters. However, the feeding capacity and interaction between zooplankton and toxic cyanobacteria vary among grazer species. In this study, laboratory feeding experiments were designed to measure the grazing rate of the copepod Cyclops vicinus on Microcystis aeruginosa and the potential microcystin (MC) accumulation in the grazer. Copepods were fed a mixed diet of the edible green alga Ankistrodesmus falcatus and toxic M. aeruginosa for 10 days. The results showed that C. vicinus efficiently ingested toxic Microcystis cells with high grazing rates, varying during the feeding period (68.9–606.3 Microcystis cells animal-1 d-1) along with Microcystis cell density. Microcystis cells exhibited a remarkable induction in MC production under grazing conditions with concentrations 1.67–12.5 times higher than those in control cultures. Furthermore, C. vicinus was found to accumulate MCs in its body with concentrations increasing during the experiment (0.05–3.21 μg MC animal-1). Further in situ studies are needed to investigate the ability of Cyclops and other copepods to assimilate and detoxify MCs at environmentally relevant concentrations before deciding on the biocontrol of Microcystis blooms by copepods.

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