Determination of photosynthetic and enzymatic biomarkers sensitivity used to evaluate toxic effects of copper and fludioxonil in alga Scenedesmus obliquus

Dewez, David; Geoffroy, Laure; Vernet, Guy; Popovic, Radovan

doi:10.1016/j.aquatox.2005.05.007

Cited by 139 publications

(77 citation statements)

References 37 publications

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“…Aquatic photosynthetic organisms represent the main source of biomass in the aquatic trophic chain and these organisms are very sensitive to the effects of copper species. It has been reported that copper may induce strong inhibition of photosynthetic electron transport mboxprocesses and oxidative stress at cellular level [12,13]. We reported recently that CuO NPs, having a core of CuO NPs and a shell of polyacrylic acid (PAA), were found to be very toxic to unicellular algae, causing inhibition of PSII electron transport capacity in Chlamydomonas reinhardtii cultures [11].…”

Section: Introductionmentioning

confidence: 99%

Evaluation of Copper Oxide Nanoparticles Toxicity Using Chlorophyll a Fluorescence Imaging in Lemna gibba

et al. 2010

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Copper oxide nanoparticles (CuO NPs), used in antifouling paints of boats, are released in the environment and can induce toxicity to aquatic organisms. In this report, we used chlorophyll a fluorescence imaging to evaluate CuO NPs toxicity in Lemna gibba. This approach allowed to evaluate the differential effect of CuO NPs on photosynthesis of whole L. gibba plants. Exposure to 0.1 to 0.4 g/L CuO NPs during 48h induced strong inhibition of photosynthetic processes resulting in a decrease of plant growth. By using fluorescence imaging, different photosynthetic parameters were evaluated simultaneously in microplate conditions. Imaging of F O fluorescence yield showed the decrease of leaf photosynthetic active surface for whole plants exposed to CuO NPs. This method showed that CuO NPs inhibited photosystem II maximal, photosystem II operational quantum yields, and photochemical quenching of fluorescence associated with electron transport. Nonphotochemical fluorescence quenching as an indicator of energy dissipation not used in photosynthesis was shown to be increased by the effect of CuO NPs. Such approach in microplate conditions provides synchronous high repetition measurements for numerous plants. This study may give a reliable methodological approach to evaluate toxicity risk of NPs in aquatic ecosystems.

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Section: Introductionmentioning

confidence: 99%

Evaluation of Copper Oxide Nanoparticles Toxicity Using Chlorophyll a Fluorescence Imaging in Lemna gibba

et al. 2010

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“…This process generates large quantities of MDA (malondialdehyde), which is commonly used as an indicator of lipid peroxidation. Additionally, these free radicals damage photosynthetic apparatus (Rama Devi and Prasad, 1998;Dewez et al, 2005;Vajpayee et al, 2005) and may also catalyze degradation of proteins through oxidative modification and increased proteolytic activity (Romero-Puertas et al, 2002). Copper disturbs the integrity of thylakoid membranes and changes their fatty acid composition (De Vos et al, 1991), interferes with the biosynthesis of photosynthetic machinery and decreases net photosynthetic rate (Cook et al, 1997;Yruela, 2005).…”

Section: Introductionmentioning

confidence: 99%

Ecophysiological tolerance of duckweeds exposed to copper

et al. 2009

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a b s t r a c tAlthough essential for plants, copper can be toxic when present in supra-optimal concentrations. Metal polluted sites, due to their extreme conditions, can harbour tolerant species and/or ecotypes. In this work we aimed to compare the physiological responses to copper exposure and the uptake capacities of two species of duckweed, Lemna minor (Lm(EC1)) and Spirodela polyrrhiza (SP), from an abandoned uranium mine with an ecotype of L. minor (Lm(EC2)) from a non-contaminated pond. From the lowest Cu concentration exposure (25 M) to the highest (100 M), Lm(EC2) accumulated higher amounts of copper than Lm(EC1) and SP. Dose-response curves showed that Cu content accumulated by Lm(EC2) increases linearly with Cu treatment concentrations (r 2 = 0.998) whereas quadratic models were more suitable for Lm(EC1) and SP (r 2 = 0.999 and r 2 = 0.998 for Lm(EC1) and SP, respectively). A significant concentrationdependent decline of chlorophyll a (chl a) and carotenoid occurred as a consequence of Cu exposure. These declines were significant for Lm(EC2) exposed to the lowest Cu concentration (25 M) whereas for Lm(EC1) and SP a significant decrease in chl a and carotenoids was observed only at 50 and 100 M-Cu. Electric conductivity (EC) and malondialdehyde (MDA) content increased after Cu exposure, indicating oxidative stress. Significant increase of EC was observed in Lm(EC2) for all Cu concentrations whereas the increase for Lm(EC1) and SP became significant only after an exposure to 50 M-Cu. On the contrary, for Lm(EC1), SP, and Lm(EC2), MDA content significantly increased even at the lowest concentration. Protein content and catalase (CAT) activity showed a decrease with an increase in Cu concentration. For the species Lm(EC1) and SP, a significant effect of copper on CAT activity was observed only at the highest concentration (100 M-Cu) whereas, for Lm(EC2), this effect started to be significant after an exposure to 50 M-Cu. Superoxide dismutase (SOD) activity increased with increasing concentrations of Cu, with a very similar trend between the three populations of duckweed. However, due to the facts that enzyme activity is expressed as units of activity per gram of protein and that protein content decreased with Cu exposure, the increase in SOD activity might partly result from a relative increase of this enzyme inside the pool of proteins. Consequently, the results obtained in our experimental conditions strongly suggest that duckweed species from the uranium-polluted area have developed mechanisms to cope with metal toxicity and that this tolerance is based on the existence of protective mechanism to limit the metal uptake rather than on an enhancement of the antioxidative metabolism.

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“…El cobre es un micronutriente esencial para el crecimiento de los organismos, pero es requerido sólo en cantidades traza, ya que a altas concentraciones es tóxico para las células al alterar las funciones de las proteínas y consecuentemente la actividad enzimática. 6,7 Este metal se encuentra normalmente como complejos en las proteínas de las células y, si se encuentra como ión libre, puede generar estrés oxidativo y daños en macromoléculas. 8 El O 2 -• y H 2 O 2 son relativamente poco reactivos, sin embargo ambos pueden interaccionar ,a través de la reacción de Fenton, con iones de metales de transición como el hierro y el cobre para producir el extremadamente reactivo OH…”

Section: Introductionunclassified

Evaluación de la toxicidad de cobre en suelos a través de biomarcadores de estrés oxidativo en eisenia foetida

Gaete¹,

Hidalgo²,

Neaman³

et al. 2010

Quím. Nova

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Recebido em 5/3/09; aceito em 19/8/09; publicado na web em 11/1/10 ASSESSMENT OF COPPER TOXICITY IN SOILS USING BIOMARKERS OF OXIDATIVE STRESS IN Eisenia foetida.Copper toxicity in soil was evaluated using biomarkers of oxidative stress (catalase enzyme activity, superoxide dismutase and lipid peroxidation) in the earthworm Eisenia foetida. Agricultural topsoils from mining areas of the Aconcagua river basin were collected. Total copper concentrations were in the range of 94-959 mg kg . Earthworms exposed to soil with exchangeable copper concentrations above 32 µg kg -1 showed an increase in catalase activity. Parameters of antioxidant activity were more sensitive than the weight change and thus can be used as appropriate biomarkers in Eisenia foetida.

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Determination of photosynthetic and enzymatic biomarkers sensitivity used to evaluate toxic effects of copper and fludioxonil in alga Scenedesmus obliquus

Cited by 139 publications

References 37 publications

Evaluation of Copper Oxide Nanoparticles Toxicity Using Chlorophyll a Fluorescence Imaging in Lemna gibba

Evaluation of Copper Oxide Nanoparticles Toxicity Using Chlorophyll a Fluorescence Imaging in Lemna gibba

Ecophysiological tolerance of duckweeds exposed to copper

Evaluación de la toxicidad de cobre en suelos a través de biomarcadores de estrés oxidativo en eisenia foetida

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