|
|
|
|
|
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 Gharbia, Hela; Yahia, Ons Kefi-daly; Cecchi, Philippe; Masseret, Estelle; Amzil, Zouher; Herve, Fabienne; Rovillon, Georges-augustin; Nouri, Habiba; M'Rabet, Charaf; Couet, Douglas; Triki, Habiba Zmerli; Laabir, Mohamed. |
Macrophytes are known to release allelochemicals that have the ability to inhibit the proliferation of their competitors. Here, we investigated the effects of the fresh leaves of two magnoliophytes (Zostera noltei and Cymodocea nodosa) and thalli of the macroalgae Ulva rigida on three HAB-forming benthic dinoflagellates (Ostreopsis cf. ovata, Prorocentrum lima, and Coolia monotis). The effects of C. nodosa and U. rigida were also tested against the neurotoxic planktonic dinoflagellate Alexandrium pacificum Litaker sp. nov (former Alexandrium catenella). Co-culture experiments were conducted under controlled laboratory conditions and potential allelopathic effects of the macrophytes on the growth, photosynthesis and toxin production of the targeted... |
Tipo: Text |
|
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00411/52200/52917.pdf |
| |
|
|
Ben-gharbia, Hela; Yahia, Ons Kefi-daly; Amzil, Zouher; Chomerat, Nicolas; Abadie, Eric; Masseret, Estelle; Sibat, Manoella; Triki, Habiba Zmerli; Nouri, Habiba; Laabir, Mohamed. |
armful benthic dinoflagellates, usually developing in tropical areas, are expanding to temperate ecosystems facing water warming. Reports on harmful benthic species are particularly scarce in the Southern Mediterranean Sea. For the first time, three thermophilic benthic dinoflagellates (Ostreopsis cf. ovata, Prorocentrum lima and Coolia monotis) were isolated from Bizerte Bay (Tunisia, Mediterranean) and monoclonal cultures established. The ribotyping confirmed the morphological identification of the three species. Maximum growth rates were 0.59 ± 0.08 d−1 for O. cf. ovata, 0.35 ± 0.01 d−1 for C. monotis and 0.33 ± 0.04 d−1 for P. lima. Toxin analyses revealed the presence of ovatoxin-a and ovatoxin-b in O. cf. ovata cells. Okadaic acid and... |
Tipo: Text |
Palavras-chave: Ostreopsis cf. ovata; Prorocentrum lima; Coolia monotis; Southern Mediterranean Sea; Growth; Toxicity. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00355/46585/46393.pdf |
| |
|
|
|