Influence of Environmental Factors on the Paralytic Shellfish Toxin Content and Profile of Alexandrium catenella (Dinophyceae) Isolated from the Mediterranean Sea

Abstract

Laboratory experiments were designed to study the toxin content and profile of the Alexandrium catenella strain ACT03 (isolated from Thau Lagoon, French Mediterranean) in response to abiotic environmental factors under nutrient-replete conditions. This dinoflagellate can produce various paralytic shellfish toxins with concentrations ranging from 2.9 to 50.3 fmol/cell. The toxin profile was characterized by carbamate toxins (GTX3, GTX4 and GTX5) and N-sulfocarbamoyl toxins (C1, C2, C3 and C4). C2 dominated at 12–18 °C, but only for salinities ranging from 10 to 25 psu, whereas GTX5 became dominant at temperatures ranging from 21 to 30 °C at almost all salinities. There was no significant variation in the cellular toxin amount from 18 °C to 27 °C for salinities ranging between 30 and 40 psu. At salinities of 10 to 25 psu, the toxin concentrations always remained below 20 fmol/cell. Toxin content was stable for irradiance ranging from 10 to 70 μmol photons/m2/s then slightly increased. Overall, the toxin profile was more stable than the toxin content (fmol/cell), except for temperature and/or salinity values different from those recorded during Alexandrium blooms in Thau Lagoon.

Alexandrium pacificum Litaker sp. nov (Group IV): Resting cyst distribution and toxin profile of vegetative cells in Bizerte Lagoon (Tunisia, Southern Mediterranean Sea)

“…In contrast, A. catenella (Group I), renamed Alexandrium fundyense by John et al (2014), from the southern coast of Chile showed a dominance of C1,2 or GTX1,4 depending on the strain (Varela et al, 2012). Significant intra and inter-specific variations in toxin profile were observed among Alexandrium populations in different ecosystems under different environmental conditions (Alpermann et al, 2010;Anderson et al, 2012;Laabir et al, 2013).…”

Toxicity and Growth Assessments of Three Thermophilic Benthic Dinoflagellates (Ostreopsis cf. ovata, Prorocentrum lima and Coolia monotis) Developing in the Southern Mediterranean Basin

“…Temperature, salinity and irradiance are the most important environmental factors influencing the growth and cell toxin content of dinoflagellate species [11,118,119,120,121,122,123]. The culture medium and origin of the water used for cultivation could also affect these biological parameters, highlighting specific requirements regarding certain trace elements [124].…”

“…The presence of new thermophilic harmful species in the Mediterranean basin has been documented in the Northern Mediterranean Sea. Their occurrence has probably been promoted by the increase of water temperature during the last few decades [8,9]; as this factor represents one of the main environmental drivers affecting growth and bloom development of phytoplanktonic species [1,10,11]. Ostreopsis ovata , Prorocentrum lima and Coolia monotis often constitute a significant part of potentially toxic epiphytic dinoflagellate assemblages.…”

Do the levels of industrial pollutants influence the distribution and abundance of dinoflagellate cysts in the recently-deposited sediment of a Mediterranean coastal ecosystem?

“…Contaminants affect the physiology of vegetative cells by acting on the levels of oxidative stress in cells (Okamoto and Colepicolo, 1998;Pinto et al, 2003) or by reducing their light-harvesting capacity and by inhibiting cell growth (Miao and Wang, 2006;Herzi et al, 2013). Under high levels of iron, cell Naple, Adriatic sea (Italy), Alfacs Bay (Spain) (Montresor, 1995;Bravo et al, 2006;Penna et al, 2010;Satta et al, 2013) Alexandrium minutum Halim * Paralytic shellfish toxins (Bravo et al, 2006) Harbour of Alexandria (Egypt), Catalonia, Arenys del mar (Spain); Ionian sea, Adriatic sea, Tyrrhenian sea, Olbia (Italy), Aegean Sea (Turkey) (Ismael and khadr, 2003;Anglès et al, 2010;Rubino et al, 2010;Penna et al, 2010;Aydin et al, 2011) Alexandrium catenella/tamarense (Whedon & Kofoid) Balech ** Paralytic shellfish toxins (Laabir et al, 2013) Aegean Sea (Turkey), Ionian Sea, Olbia, (Italy), Thau lagoon (France), Tarragona and Barcelona Harbours (Spain) (Bravo et al, 2006;Satta et al, 2010;Rubino et al, 2010;Aydin et al, 2011) Lingulodinium polyedrum (Stein) Dodge Lingulodinium sp ** Yessotoxin (Paz et al, 2004) Ionian Sea, Adriatic sea (Italy), Catalan sea, Arenys del mar, Alfacs and Fangar bays (Spain) Penna et al, 2010;Satta et al, 2010Satta et al, , 2013) Gonyaulax cf. spinifera complex (Claparéde et Lachmann) Diesing * Yessotoxin (Rhodes et al, 2006) Arenys del mar (Spain), Olbia (Italy) Protoceratium reticulatum (Claparède et Lachmann) Butschli * Yessotoxin (Paz et al, 2004) Adriatic sea (Italy), Alfacs and Fangar bays Satta et al, 2013) Protoperidinium claudicans (Paulsen) Balec ** Adriatic sea, Tyrrhenian sea, Olbia and Syracuse bay (Italy) Arenys harbour, Catalonia, Alfacs and Fangar bays (Spain) Garcés et al, 2010;Satta et al, 2013) Protoperidinium leonis * Non toxic Ionian sea ) Protoperidinium compressum (Abé) ...…”