|
|
|
|
|
| Ben Garali, Sondes Melliti; Sahraoui, Ines; Ben Othman, Hiba; Kouki, Abdessalem; De La Iglesia, Pablo; Diogene, Jorge; Lafabrie, Celine; Andree, Karl B.; Fernandez-tejedor, Margarita; Mejri, Kaouther; Meddeb, Marouan; Pringault, Olivier; Hlaili, Asma Sakka. |
| This study investigates the effects of polycyclic aromatic hydrocarbons (PAHs) on two potentially toxic Pseudonitzschia hasleana and P. mannii, isolated from a PAH contaminated marine environment. Both species, maintained in non-axenic cultures, have been exposed during 144 h to increasing concentrations of a 15 PAHs mixture. Analysis of the domoic acid, showed very low concentrations. Dose?response curves for growth and photosynthesis inhibition were determined. Both species have maintained their growth until the end of incubation even at the highest concentration tested (120 ?g l-1), Nevertheless, P mannii showed faster growth and seemed to be more tolerant than P. hasleana. To reduce PAH toxicity, both species have enhanced their biovolume, with a... |
| Tipo: Text |
Palavras-chave: Diatoms; Pseudo-nitzschia; PAHs mixtures; Biodegradation; Eco-toxicology. |
| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00690/80215/83300.pdf |
| |
|
|
| Couet, Douglas; Pringault, Olivier; Bancon-montigny, Chrystelle; Briant, Nicolas; Poulichet, Francoise Elbaz; Delpoux, Sophie; Yahia, Ons Kefi-daly; Hela, Bengharbia; Charaf, M'Rabet; Herve, Fabienne; Rovillon, Georges-augustin; Amzil, Zouher; Laabir, Mohamed. |
| Controlled laboratory experiments were conducted to test the effects of copper (Cu2+) and butyltins (BuT) on the growth, photosynthetic activity and toxin content of two HABs (Harmful Algal Blooms) dinoflagellates, the planktonic Alexandrium catenella and the benthic Ostreopsis cf. ovata. Microalgae were exposed to increasing concentrations of Cu2+ (10−4 to 31 nM) or BuT (0.084 to 84 nM) for seven days. When considering the growth, EC50 values were 0.16 (±0.09) nM and 0.03 (±0.02) nM of Cu2+ for A. catenella and O. cf. ovata, respectively. Regarding BuT, EC50 was 14.2 (±6) nM for O. cf. ovata, while A. catenella growth inhibition appeared at BuT concentrations ≥27 nM. Photosynthetic activity of the studied dinoflagellates decreased with increasing Cu and... |
| Tipo: Text |
Palavras-chave: Alexandrium catenella; Ostreopsis cf. ovata; Cu; Butyltin; Photosynthesis; Toxins. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00418/52970/53896.pdf |
| |
|
| |
|
|
| Ben Othman, Hiba; Pringault, Olivier; Louati, Hela; Hlaili, Asma Sakka; Leboulanger, Christophe. |
| Effects of sediment-released contaminants and nitrogen were assessed on phytoplankton communities sampled from Thau lagoon (France, Mediterranean Sea) and one close offshore marine station. Phytoplankton was exposed to sediment elutriate (seawater containing a mix of metals, organic chemicals, and nutrients) or to ammonium enrichment for four days using immersed microcosms exposed to natural conditions of light and temperature. Functional (production - respiration balance) and structural (taxonomy and cell densities) responses of the phytoplankton community were assessed. In the lagoon, both treatments stimulated phytoplankton growth, compare to controls. Conversely in the offshore station, the phytoplankton growth was stimulated only with the sediment... |
| Tipo: Text |
Palavras-chave: Sediment resuspension; Mediterranean lagoon; Contaminants; Nutrients; Phytoplankton community. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00352/46364/46317.pdf |
| |
|
|
| Fouilland, Eric; Gales, Amandine; Beaugelin, Ines; Lanouguere, Elodie; Pringault, Olivier; Leboulanger, Christophe. |
| When microalgae are exposed to contaminants, the role of associated bacteria within the phycosphere, the microenvironment surrounding algal cells, remains largely unknown. The present study investigated the importance of algae-associated bacteria on the responses of microalgae growth to metallic and organic toxicant exposure. The effects of a polluted sediment elutriate, and of metal or pesticide mixtures at environmentally relevant concentrations (<10 μg L−1) were assessed on the growth of two microalgae strains: Isochrysis galbana, a prymnesiophyte, and Thalassiosira delicatula, a centric diatom. Both cultures were maintained as axenic or bacterized under similar conditions in batch cultures. In axenic conditions, the metal mixture addition at low... |
| Tipo: Text |
Palavras-chave: Microbial interactions; Metallic and pesticide contaminants; Sediments. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00453/56422/58325.pdf |
| |
|
| |
|
|
| Bancon-montigny, Chrystelle; Gonzalez, Catherine; Delpoux, Sophie; Avenzac, Muriel; Spinelli, Sylvie; Mhadhbi, Takoua; Mejri, Kaouther; Hlaili, Asma Sakka; Pringault, Olivier. |
| The potential of remobilization of pollutants is a major problem for anthropogenic ecosystems, because even when the anthropogenic source of pollution is identified and removed, pollutants stored in sediments can be released into the water column and impact pelagic communities during sediment resuspension provoked by dredging, storms or bottom trawling. The objectives of the present study were to assess the changes observed in the chemical composition of the water column following resuspension of a polluted marine sediment and the consequences for the chemical composition of adjacent marine waters according to season. For that purpose, an experimental sediment resuspension protocol was performed on four distinct occasions, spring, summer, fall and winter,... |
| Tipo: Text |
Palavras-chave: Lagoon; Offshore; Trace metal elements; Pesticides; PAHs; Enrichment factor; Elutriate. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00505/61620/65644.pdf |
| |
|
|
| Blanchet, Marine; Pringault, Olivier; Panagiotopoulos, Christos; Lefevre, Dominique; Charriere, Bruno; Ghiglione, Jean-francois; Fernandez, Camila; Aparicio, Fran L.; Marrase, Celia; Catala, Philippe; Oriol, Louise; Caparros, Jocelyne; Joux, Fabien. |
| Heterotrophic bacterial communities in marine environments are exposed to a heterogeneous mixture of dissolved organic compounds with different bioreactivity that may control both their activity and composition. The coastal environment is an example of a mixing area where recalcitrant allochthonous organic matter from rivers can encounter labile organic matter from marine phytoplanktonic blooms. The objective of this study was to explore the effects of mixed qualities of dissolved organic matter (DOM) on bacterial community activity (BCA) and bacterial community composition (BCC) and to test for a priming effect when DOM sources are added in combination. Coastal marine bacterial communities were incubated separately with a mixture of amino acids and with... |
| Tipo: Text |
Palavras-chave: Dissolved organic matter; Biodegradation; Coastal waters; Bacterial community composition; Priming effect. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00625/73737/74701.pdf |
| |
|
|
|
