Toxin content of Ostreopsis cf. ovata depends on bloom phases, depth and macroalgal substrate in the NW Mediterranean Sea

Publication date: Available online 14 December 2019Source: Harmful AlgaeAuthor(s): Gémin Marin-Pierre, Réveillon Damien, Hervé Fabienne, Pavaux Anne-Sophie, Tharaud Maxime, Séchet Véronique, Bertrand Samuel, Lemée Rodolphe, Amzil ZouherAbstractOver the last fifteen years, blooms of the genus Ostreopsis have been reported more frequently and at higher abundances in the Mediterranean area. Ostreopsis cf. ovata is known to produce ovatoxins (OVTXs), structural analogues of palytoxin, which is one of the most potent non-polymeric toxins. However, the production of OVTXs is poorly characterized in situ. The present study focuses on toxin content and profile according to the bloom phase during summer 2017 in Villefranche-sur-Mer, France (NW Mediterranean Sea), depth (from 0.5 to 5 m) and three different macroalgal substrates of this epiphytic dinoflagellate (Padina pavonica, Dictyota spp. and Halopteris scoparia). Ovatoxin quantification of all samples was performed by liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS). The bloom started at the end of June and declined in mid-July, showing the typical seasonal pattern of the NW Mediterranean Sea area. The peak was observed on the 10 July with 1.8 × 106 cells/g FW and 1.7 × 104 cells/L for benthic and planktonic cells, respectively. Total toxin content of cells, collected using artificial substrates, increased during the exponential and stationary growth phases. After reaching a maximum concentr...
Source: Harmful Algae - Category: Environmental Health Source Type: research