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Occurrence of microcystins and anatoxin-a in eutrophic lakes of Saint Petersburg, Northwestern Russia

Chernova E., Russkikh I., Voyakina E., Zhakovskaya Z.

Oceanological and Hydrobiological Studies

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2016

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Vol. 45, No. 4

466--484

EN

Cyanobacteria are natural components of many freshwater bodies worldwide. In Russian lakes, the presence of potentially toxic cyanobacteria was also frequently observed. Our study was conducted in Sestroretskij Razliv Lake (Razliv) and Lower Suzdal Lake (Suzdal) in Saint Petersburg region, Northwestern Russia, which differ from one another in eutrophic status and composition of the phytoplankton community. In large, shallow, artificial and hypertrophic Razliv, Aphanizomenon flos-aquae and Microcystis spp. dominated. Fourteen microcystin variants were identified in this lake. The maximum concentration of extracellular microcystins was 41.37 μg l−1. In eutrophic and shallow Suzdal, dominated by Planktothrix agardhii, nine microcystin variants and anatoxin-a (<0.54 μg l−1) were found. The maximum total concentration of extracellular MCs in this lake was 2.89 μg l−1. Regular studies into the production of cyanotoxins in these water bodies were carried out for the first time. The analyses performed with the application of high-resolution tandem mass spectrometry revealed the presence of microcystins in 59% of the samples collected during a 3-year study. Since both lakes are used for recreational purposes, the regular monitoring program should be implemented to protect water users from a potential risk that was identified in our study.

2

Application of Biotests in Cyanobacterial Extract Toxicity Assessment

Sierosławska A., Rymuszka A., Skowroński T.

Archives of Environmental Protection

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2014

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Vol. 40, no. 3

115--121

EN

The aim of the study was to determine the toxicity of the extract obtained from the cyanobacterial cells derived from the waters of Zemborzycki dam reservoir with use of a battery of biotests. The taxonomic identiﬁcation of the bloom-forming cyanobacteria revealed high abundance of Aphanizomenon ﬂos-aquae and Dolichospermum spp. (Anabaena spp.) and in a lower degree of Microcystis aeruginosa and Planktothrix agardhii. In the extract obtained from concentrated cyanobacterial cells, hepatotoxin microcystin-LR at a concentration of 22.89 ± 3.74 μg/L and neurotoxin Antx-a at 13.02 ± 0.01 μg/L have been detected. Toxicity of the extract was evaluated with the following assays: Daphtoxkit F magna with the crustacean Daphnia magna, Thamnotoxkit F with the crustacean Thamnocephalus platyurus, Rotoxkit F with the rotifer Brachionus calyciﬂorus and Protoxkit F with ciliate Tetrahymena thermophila. The most sensitive organism among all studied was T. platyurus for which EC50 was estimated to be 1.2% of the initial extract concentration. On the basis of the highest obtained value of the toxicity unit (TU = 83) the studied sample was classiﬁed to the IV class, which is of high acute toxicity. Additionally, it was found that reactivity on cyanobacterial products differs greatly among organisms used in bioassays, which indicate the need for using a set of biotests.

PL

Celem pracy była ocena toksyczności ekstraktu uzyskanego z komórek cyjanobakterii obecnych w wodzie pobranej podczas zakwitu sinic z Zalewu Zemborzyckiego, z wykorzystaniem zestawu biotestów. Identyfikacja taksonomiczna wykazała w badanej próbce wysoką liczebność Aphanizomenon fl os-aquae i Dolichospermum spp. (Anabaena spp.) oraz w mniejszym stopniu Microcystis aeruginosa i Planktothrix agardhii. Analiza HPLC ekstraktu uzyskanego z zagęszczonych komórek cyjanobakterii wykazała obecność mikrocystyny-LR w stężeniu 22,89 μg/L oraz anatoksyny-a w stężeniu 13.02 μg/L. Stopień toksyczności uzyskanego ekstraktu oceniano na podstawie reakcji organizmów testowych, z użyciem następujących biotestów: Daphtoxkit F magna (Daphnia magna), Thamnotoxkit F (Thamnocephalus platyurus), Rotoxkit F (Brachionus calyciflorus) oraz Protoxkit F (Tetrahymena thermophila) (Microbiotests Inc., Belgia). Przeprowadzone badania wykazały szczególnie silne działanie toksyczne analizowanego ekstraktu wobec T. platyurus (24hEC50 oszacowane na 1,2% ekstraktu wyjściowego). Wyraźny efekt toksyczny obserwowany był także wobec B. calyciflorus i w mniejszym stopniu wobec T. thermophila. Natomiast największą odporność na toksyczne działanie ekstraktu wykazywała D. magna. Na podstawie uzyskanych wartości TU (jednostek toksyczności) badany ekstrakt zaliczony został do IV klasy toksyczności, tj. o wysokiej toksyczności ostrej. Z przeprowadzonych badań wynika, że organizmy na których wykonywane są testy toksyczności wykazują zróżnicowaną wrażliwość na produkty cyjanobakterii, stąd ocena toksyczności próbek zawierających tego typu substancje powinna być prowadzona z wykorzystaniem jak najszerszego zestawu biotestów.

3

Simultaneous accumulation of anatoxin-a and microcystins in three fish species indigenous to lakes affected by cyanobacterial blooms

Pawlik-Skowrońska B., Toporowska M., Rechulicz J.

Oceanological and Hydrobiological Studies

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2012

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Vol. 41, No. 4

53-65

EN

A four-year study carried out in a lake with perennial water blooms caused by toxigenic Planktothrix agardhii (Oscillatoriales) and Anabaena lemmermanii, Anabaena flos-aquae, Anabaena spp. and Aphanizomenon issatchenkoi (Nostocales) revealed that the lake-dwelling fish were threatened by simultaneous exposure to intracellular and extracellular microcystins (MCs) as well as anatoxin-a (ANTX). Higher contents of anatoxin-a and microcystins were found in livers than in fish muscles. This is the first report on ANTX accumulation in the common fish, indigenous to European freshwaters during perennial cyanobacterial blooms. Generally, the omnivorous roach (Rutilus rutilus) and Prussian carp (Carassius gibelio) accumulated higher amounts of MCs in their tissues compared to mostly predacious perch (Perca fluviatilis), and similar amounts of ANTX. The long-lasting presence of MCs exceeding the safe levels for consumption was found in fish muscles. ANTX accumulation in fish muscles (up to 30 ng g-1 FW) suggests the probability of its transfer in a food chain.

4

Diversity and distribution of cyanobacterial toxins in the Italian subalpine lacustrine district

Cerasino L., Salmaso N.

Oceanological and Hydrobiological Studies

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2012

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Vol. 41, No. 3

54-63

EN

Nine lakes (Garda, Maggiore, Como, Iseo, Lugano, Idro, Pusiano, Ledro, and Levico) located in the Italian subalpine lacustrine district were chosen for a comparative study of the diversity and distribution of cyanobacterial toxins. All nine lakes are known to host different toxic cyanobacteria, mainly Planktothrix rubescens. An analytical protocol has been used, based on LC-MS technique, for determining 20 different toxins (14 microcystins, 2 nodularins, anatoxin-a and 3 cylindrospermopsins). In the investigation, microcystins were found in all lakes on all sampling dates. Anatoxin-a could be detected in 6 lakes, but it was only present in 4 lakes on all sampling dates (lakes Garda, Iseo, Como, and Maggiore). Nodularins and cylindrospermopsins were not detected at all. The number of microcystins detected in the survey was 9, but 4 were the most abundant (dmRR, YR, dmLR, and LR); they were differently distributed among the lakes, thus providing each lake a unique toxic potential. Statistical analysis showed positive correlations between total microcystin concentrations and eutrophication indicators and also between anatoxin-a concentrations and water temperature, suggesting that anthropic and climate-related stressors can have different impacts on the presence of different cyanotoxins.

5

Blooms of toxin-producing Cyanobacteria - a real threat in small dam reservoirs at the beginning of their operation

Pawlik-Skowrońska B., Toporowska M.

Oceanological and Hydrobiological Studies

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2011

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Vol. 40, No.4

30-37

EN

Large and harmful cyanobacterial blooms appeared in two newly-built artificial reservoirs shortly after being filled with water. Taxonomic composition of cyanobacterial communities was highly variable in both water bodies and fast species replacement was observed. In the first year of the operation of the smaller Konstantynów Reservoir, the mass development of Anabaena flos-aquae and Planktolyngbya limnetica (48.7 and 53.6% of the cyanobacterial abundance) occurred in summer, while in autumn the dominance of Planktothrix agardhii (99.9%, 14.95 × 106 ind. dm-3 ) was noted. The surface scum developed in summer consisted of An. flos-aquae that contained high amounts of anatoxin-a (1412.4 μg AN-a dm-3 of scum) and smaller amounts of microcystins (10 μg eq. MC-LR dm-3 of scum). In the larger Kraśnik Reservoir, Aphanizomenon flos-aquae occurred in high abundance in spring and summer, however, it was replaced created thick surface scum. Simultaneously, a hazardous increase in the total concentration of microcystins (from 13.6 to 788.5 μg eq. MC-LR dm-3 of water with scum) and anatoxin-a (from 0.03 to 43.6 μg dm-3) was observed.

6

BMAA i inne neurotoksyny cyjanobakterii

Błaszczyk A., Mazur-Marzec H.

Polish Hyperbaric Research

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2006

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Nr 4(17)

7-14

PL

Cyjanobakterie są bogatym źródłem związków biologicznie aktywnych. Wiele z nich znalazło praktyczne zastosowanie w medycynie, kosmetyce i rolnictwie. Te same organizmy produkują również metabolity wtórne o działaniu toksycznym. Należą do nich hepatotoksyny, dermatotoksyny oraz neurotoksyny. Neurotoksyny (anatoksyny i saksitoksyny), ze względu na niską wartość dawki letalnej należą do najsilniejszych toksyn naturalnych. Do niedawna sądzono, że zakwity cyjanobakterii produkujących związki o działaniu neurotoksycznym występują znacznie rzadziej niż zakwity gatunków produkujących hepatotoksyny. Ostatnio jednak odkryto, u wielu cyjanobakterii, obecność neurotoksycznego aminokwasu BMAA (ß-Nmetyloamino- L-alanina). Przypuszcza się, że związany jest on z przypadkami choroby Alzheimera zarejestrowanymi w Kanadzie.

EN

Cyanobacteria are a rich source of biologically active compounds. Many of them have been practically used in medicine, cosmetics and agriculture industries. The same organisms also produce secondary metabolites that act as toxins. This group of toxins consists from hepatotoxins, dermatotoxins,and neurotoxins. Due to low lethal dose value the neurotoxins (anatoxins and saxitoxins) are considered to be the most toxic natural substances. Until recently, it has been thought that cyanobacteria species producing compounds with neurotoxic properties occur considerably more rarely than blooms of species producing hepatotoxins. However, in many cyanobacteria the presence of neurotoxic BMAA (ß-N-methylamine-Lalanine) has been lately discovered. It is supposed that BMAA may be related to Alzheimer disease cases recorded in Canada.

7

Relationship between Cyanobacterial bloom composition and anatoxin-a and microcystin occurrence in the eutrophic dam reservoir (SE Poland)

Pawlik-Skowrońska B., Skowroński T., Pirszel J., Adamczyk A.

Polish Journal of Ecology

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2004

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Vol. 52, nr 4

479-490

EN

Long-lasting cyanobacterial blooms were observed over summer periods 2001-2003 in the highly eutrophic dam reservoir (Zemborzycki Reservoir near Lublin, SE Poland) loaded with nitrogen and phosphorus by the river Bystrzyca. Chloriphyll a content and water transparence reached in summer periods 2002-2003 average values 115-129 [mi]g l^-1 and 0.5 m, respectively. The blooms consisted of eight taxa of Cyanobacteria occurring in different proportions: Aphanizomenon flos-aquae, Anabaena circinalis, Anabaena spiroides, Anabaena flos-aquae, Planktothrix agardhii, Microcystis aeruginosa, Microcystis viridis, Microcystis wesenbergii. At decreased average water temperature and increased concentration of dissolved ammonium-nitrogen in summer 2003, compared with two earlier years, a replacement of dominant Aph. flos-aquae to P. agardhii was observed. The total abundance of potential microcystin producers was positively correlated with the content of these hepatotoxins in the reservoir water. First time in Poland, mass occurrence of Anabaena strains producing anatoxin-a was observed. Anatoxin-a concentration in the reservoir water was positively correlated with total abundance of 3 taxa of Anabaena. It was no such correlation with Aph. flos-aquae.

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Cyanobacterial toxins in fresh and brackish waters of Pomorskie Province (northern Poland)

Mazur H., Lewandowska J., Błaszczyka A., Kot A., Pliński M.

Oceanological and Hydrobiological Studies

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2003

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Vol. 32, No. 1

15-26

EN

Hepatotoxic cyclic peptides and neurotoxic alkaloids are the most common groups of cyanobacterial toxins. They pose a serious threat to human and animal health; each year they are responsible for several cases of animal fatalities (mammals, fish and birds). In Polish water bodies toxic blooms of cyanobacteria are also frequently observed. In this work, a procedure for anatoxin-a analysis has been modified to obtain a sensitive and selective method for routine studies of bloom samples. The presence of cyanobacterial neuro and hepatotoxins in fresh and brackish waters of Pomorskie Province was examined. Hepatotoxins, microcystins or nodularin, were detected in all phytoplankton samples dominated by the cyanobacteria of Microcystis and Anabaena genera or by Nodularia spumigena. HPLC-PDA analysis showed the presence of anatoxin-a only in one sample collected in coastal waters of the Gulf of Gdańsk and dominated by Anabaena.