Effects of two synthetic pyrethroids on Arthrospira platensis Gomont growth and antioxidant parameters

The transport of pesticides from application areas to other areas results in pesticide contamination and this sort of contamination has led to unexpected environmental problems worldwide. It is important to determine the responses of phytoplanktonic organisms to these chemicals for an understanding of the effects of pesticides on aquatic ecosystems. In this study, Arthrospira platensis Gomont cyanobacteria were exposed to different concentrations of the pesticides cypermethrin (0-50 µg mL-1) and deltamethrin (0-2 µg mL-1). Changes in chlorophyll-a concentration, the absorbance of OD560, antioxidant parameters (SOD, APX, GR, MDA, H2O2, and proline) were determined under the pesticide exposure. Our results showed that there is a decrease in OD560 absorbance and chlorophyll-a content proportionate to the increase of pesticide levels. Superoxide dismutase enzyme activity decreased with Cyp and Dlm application in A. platensis cultures. Glutathione reductase enzyme activity also decreased with Cyp applications but did not change with Dlm application. Ascorbate peroxidase enzyme activity increased with Cyp treatments but did not change with Dlm applications. Although malondialdehyde and hydrogen peroxide contents did not change with Cyp applications, they increased with Dlm applications. Proline contents increased with Cyp applications but decreased with Dlm applications. In conclusion, deltamethrin is more toxic than cypermethrin in the concentrations applied

Oxidative stress in Arthrospira platensis by two organophosphate pesticides

Abstract Although it is known that organophosphate insecticides are harmfull to aquatic ecosystems, oxidative damages caused by Dimethoate and Chlorpyrifos are not studied on Arthrospira platensis Gomont. In this study, various Chlorpyrifos (0-150 µg mL-1) and Dimethoate (0-250 µg mL-1) concentrations were added to the culture medium in laboratory to evaulate growth rate, chlorophyll-a content and antioxidant parameters of A. platensis. Optical Density (OD560) and chlorophyll-a decreased compared to the control for seven days in both pesticide applications. Superoxide dismutase (SOD) activity increased at 50 µg mL-1 Chlorpyrifos concentration but it decreased at all concentrations. Although Ascorbate peroxidase (APX) and glutathione reductase (GR) activities increased with Chlorpyrifos application, they did not change with Dimethoate application. Malondialdehyde (MDA) amount decreased at 150 µg mL-1 Chlorpyrifos concentration but it increased in Dimethoate application. The H2O2 content were increased in both applications. Proline decreased in 50 and 75 µg mL-1 Chlorpyrifos concentrations and increased at 150 µg mL-1 concentration, while it increased at 25 µg mL-1 Dimethoate concentration. The results were tested at 0.05 significance level. These pesticides inhibit A. platensis growth and chlorophyll-a production and cause oxidative stress. The excessive use may affect the phytoplankton and have negative consequences in the aquatic ecosystem

Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.Peer reviewe

Schiff bazı komplekslerinden cd(8Q)2(SCN)2’nin in vitro genotoksik etkileri

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.İlaç hammaddesi olarak araştırılmak üzere sentezlenen Cd(8Q)2(SCN)2 Schiff bazı kompleksinin insan periferal lenfositlerinde meydana getirdiği in vitro genotoksik etkileri belirlemek amacıyla yapılmış bu çalışmada kromozomal anomalilikler ve mikronukleus testleri kullanılmıştır.1, 2, 4, 6, ve 8 µg/ml dozlarla yapılan çalışmalar sonucunda 24 saat süre ile uygulanan kromozomal anomalilikler testinde, kontrol gruplarına göre hem kromozomal anomalilik frekansı hem de anormal hücre yüzdesi bakımından 4 µg/ml dozdan itibaren anlamlı artış gözlenirken 48 saat sürelik uygulamada 2 µg/ml dozdan itibaren anlamlı artış gözlenmiştir. 48 saat süre ile uygulanan mikronukleus testinde ise 4 µg/ml doz negatif kontrol grubuna göre anlamlı bulunmuştur. 48 saat süreli uygulamalarda 6 ve 8 µg/ml dozların periferal lenfositler üzerine sitotoksik etkisi sebebiyle düşük dozda hücre bölünmesi olmuş ve sayım yapılamamıştır.In this study, chromosomal abberation and micronucleus tests were used to determine in vitro genotoxic effects occuring on human peripheral lymphocytes by Cd(8Q)2(SCN)2 with schiff base complex as synthesized drug raw material for research .In the results of reseach explored with 1, 2, 4, 6, and 8 µg/ml doses, in chromosomal abberation test applied with 24 h perioud, doses as from 4 µg/ml were observed significantly increase from controls when in chromosomal abberation test applied with 48 h perioud, doses as from 2 µg/ml were observed significantly rise from controls at both chromosomal abberation frequency and abnormal cell percentageIn the micronucleus test applied 48 h period, 4 µg/ml dose were detected significantly difference from negatif control. In the application which was made with 48 h period due to being cytotoxicity effects of 6 and 8 µg/ml doses on human peripheral lymphocytes the cell proliferations decreased and data was not got from these doses

Determination of changes in

Toxic stress caused by pesticides changes the function and structure of the aquatic ecosystem via impressing to species composition. Therefore it is necessary to determine the reaction of cyanobacteria to pesticides for comprehend the effects of these substances on the aquatic ecosystems. This study aims to determine the toxicity and oxidative stress that Lambda cyhalothrin may cause in cyanobacteria, one of the primary producers in lake ecosystems. For these reasons, the changes in chlorophyll-a content, OD560 absorbance, the antioxidant enzyme acitvities such as superoxidedismutase (SOD), ascorbate peroxidase (APX), and glutathione reducatse (GR) were assessed to carry out the effect of Lambda cyhalothrin concentrations (between 6.25 and 100 μg ml−1) on Arthrospira platensis. EC50 value is calculated as 11.94 μg m l−1 Lambda cyhalothrin concentrations. SOD and APX activities was statistically different from the control at 100 μg m l−1 Lambda cyhalothrin application compared to control in A. platensis-M2 cells. On the other hand, GR activity did not effect significantly. According to our results, we may conclude that Lambda cyhalothrin concentrations used in this study inhibited the growth of A. platensis cells in a time and dose-dependent manner, as indicated by lowered chlorophyll-a content and OD560 values and Lambda cyhalothrin caused oxidative stress in A. platensis cells. As a result, the restriction of Lambda cyhalothrin using at the certain concentrations may be a step to prevent pesticide pollution in the environment.This study aims to determine the toxicity of Lambda cyhalothrin may cause in cyanobacteria, one of the primary producers in lake ecosystems. According to our results, we may conclude that Lambda cyhalothrin inhibited the growth of A. platensis and it caused oxidative stress in the organism

Bazı pestisitlerin arthrospira platensis M2 alginin gelişimi ve antioksidan parametreler üzerine etkisi

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Pestisitler sadece hedef organizmaya değil aynı zamanda çevredeki diğer organizmalara da toksik olması bakımından dünya genelinde önemli bir sorundur. Pestisitlerin uygulandıkları alandan başka bölgelere taşınması pestisit kontaminasyonu ve istenmeyen çevresel sorunlara neden olur. Pestisitlerin sucul ekosistemlerdeki etkisinin belirlenmesi adına birincil üreticilerden olan fitoplanktonik canlıların pesitisitlere verdiği yanıtları belirlemek son derece önemlidir. Bu çalışmada A. platensis algi Azadirachtin, Chlorpyrifos, Cypermethrin, Delthametrin, Dimethoate, İmidakloprit, Thiakloprit pestisitlerinin farklı konsantrasyonlarına maruz bırakılmıştır. Böylece pestisit türüne ve konsantrasyonuna bağlı olarak canlının OD560 absorbansındaki, klorofil-a miktarındaki ve antioksidan parametrelerindeki (SOD, APOD, GR, MDA, H2O2 ve prolin) değişimler belirlenmiştir. Pestisit konsantrasyonlarındaki artışa paralel olarak bütün pestisit uygulamalarında OD560 absorbansında ve klorofil-a miktarında azalma görülmüştür. Bu parametreler açısından uygulanan konsantrasyonlar kıyaslandığında en toksik Deltamethrin pestisiti olarak belirlenmiştir. SOD aktivitesinde konsantrasyonlar kıyaslandığında en fazla azalma Azadiractin uygulamasında meydana gelmiştir. Thiakloprit uygulamasında ise SOD enzim aktivitesi konsantrasyon artıkça artış göstermiştir. APOD aktivitesinde en fazla azalma İmidakloprit uygulamasında gözlemlenmiştir. GR enzim aktivitesinde en fazla azalmayı Cypermethrin uygulaması göstermiştir. MDA miktarında en fazla artış ise Dimethoate uygulamasında görülmüştür. H2O2 miktarındaki artış en fazla Azadirachtin uygulamasında meydana gelirken, en fazla prolin artışı Chlorpyrifos uygulamasında gerçekleşmiştir. Sonuç olarak, uygulanan konsantrasyonlar kıyaslandığında Deltamethrin'in diğer pestisitlerden daha toksik olduğu ve enzim aktivitelerinde değişiklik oluşturmamasına rağmen, MDA ve H2O2 miktarlarını artırdığı görülmektedir.Pesiticides are important problems in world wide because they affect not only target organisms but also non-target organisms. The transport of pesticides from application areas to other areas results in pesticide contamination and unexpected enviromental problems. The determining the responses of phytoplanktonic organisms to pesiticides are important for understanding the effects of pesticides on aquatic ecosystems. In this study, A.platensis was exposed to different concentrations of pesiticides of Azadirachtin, Chlorpyrifos, Cypermethrin, Delthametrin, Dimethoate, Imidaclopride, and Thiaclopride. In this manner, changes in OD560, chlorophyll-a concentration and antioxidant parameters (SOD, APX, GR, MDA, H2O2 and proline) was determined. During the study, OD560 and chloropyll-a contents of A.platensis decreased with the increasing pesticide levels. Deltamethrin is the most toxic pesticide among the others. The Azadirachtin treatment caused to maximum decrease in SOD acitivity but the SOD activity increase according with the increase of pesiticide levels in Thiaclopride treatment. The maximum decrease of the APOD acitivity is observed in Imidaclopride treatment. The maximum decrease of the GR acitivity is observed in Cypermethrin treatment. The maximum increase of the MDA content is observed in Dimethoate treatment. While the maximum increase of the H2O2 content is observed in Azadirachtin treatment, the maximum increase of the proline is observed in Chlorpyrifos treatment. In conclusion, Deltamethrin is more toxic than the other pesticides according to concentrations. The enzyme activities did not change, however MDA and H2O2 contents are incerased with the treatment of Deltamethrin

Phytoplankton dynamics and structure, and ecological status estimation by the Q assemblage index: a comparative analysis in two shallow Mediterranean lakes

The aim of this research was to compare the phytoplankton structure on the basis of environmental variables and test the Q assemblage index based on phytoplankton functional groups in two shallow Mediterranean lakes [ Lake Taskisigi (LT) and Lake Little Akgol (LLA)] in the north of Turkey. Variations in the phytoplankton structure and environmental parameters were analyzed monthly at two stations of each lake between January 2013 and December 2013. We showed that total phosphorus (TP) values were vital in shaping phytoplankton biomass in eutrophic LLA. Nitrate-nitrogen (NO3-N), TP, z(mix)/z(eu), and macrophyte coverage are important in shaping the differences in dominant phytoplankton functional groups between two lakes. Generally, diversity values were similar between the two lakes and environmental parameters had no effect on diversities to constitute significant differences. The assessment using the Q index gave compatible results for determining the ecological status of LT and LLA