Abstract
Ciguatera poisoning is a foodborne disease caused by the consumption of seafood contaminated with ciguatoxins (CTXs) produced by dinoflagellates in the genera Gambierdiscus and Fukuyoa. Ciguatera outbreaks are expected to increase worldwide with global change, in particular as a function of its main drivers, including changes in sea surface temperature, acidification, and coastal eutrophication. In French Polynesia, G. polynesiensis is regarded as the dominant source of CTXs entering the food web. The effects of pH (8.4, 8.2, and 7.9), Nitrogen:Phosphorus ratios (24N:1P vs. 48N:1P), and nitrogen source (nitrates vs. urea) on growth rate, biomass, CTX levels, and profiles were examined in four clones of G. polynesiensis at different culture age (D10, D21, and D30). Results highlight a decrease in growth rate and cellular biomass at low pH when urea is used as a N source. No significant effect of pH, N:P ratio, and N source on the overall CTX content was observed. Up to ten distinct analogs of Pacific ciguatoxins (P-CTXs) could be detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in clone NHA4 grown in urea, at D21. Amounts of more oxidized P-CTX analogs also increased under the lowest pH condition. These data provide interesting leads for the custom production of CTX standards.
Highlights
Ciguatera poisoning (CP) is the most prevalent, phycotoxin-related seafood intoxication affecting mainly populations living in tropical and subtropical areas of the world
The mean growth rates exhibited by each G. polynesiensis strain 10 days (D10) and 21 days (D21)
Regarding the effect of pH on G. polynesiensis toxin production, this study showed that acidification of the culture medium stimulated the production of more polar forms of Pacific ciguatoxins (P-CTXs) in this species, i.e., P-CTX3B/C
Summary
Ciguatera poisoning (CP) is the most prevalent, phycotoxin-related seafood intoxication affecting mainly populations living in tropical and subtropical areas of the world. CP cases occur after the consumption of seafood contaminated with toxins known as ciguatoxins (CTXs) that are produced by dinoflagellates in the genera Gambierdiscus and Fukuyoa. Eighteen species of Gambierdiscus are recognized worldwide [3,4,5,6,7,8,9,10,11,12,13,14]. The phylogeny of these species based on large subunit ribosomal ribonucleic acid (LSU rDNA) D8–D10 region sequences is provided by Kretzschmar et al [11]. Ciguatoxin production has been shown by the neuroblastoma cell-based assay (CBA-N2a) to vary considerably according to species [15,16] but, interestingly, has only been confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in G. polynesiensis since the genus Gambierdiscus has been enlarged from
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
