Toxin Profiles of Okadaic Acid Analogues and Other Lipophilic Toxins in Dinophysis from Japanese Coastal Waters

Abstract

The identification and quantification of okadaic acid (OA)/dinophysistoxin (DTX) analogues and pectenotoxins (PTXs) in Dinophysis samples collected from coastal locations around Japan were evaluated by liquid chromatography mass spectrometry. The species identified and analyzed included Dinophysis fortii, D. acuminata, D. mitra (Phalacroma mitra), D. norvegica, D. infundibulus, D. tripos, D. caudata, D. rotundata (Phalacroma rotundatum), and D. rudgei. The dominant toxin found in D. acuminata was PTX2 although some samples contained DTX1 as a minor toxin. D. acuminata specimens isolated from the southwestern regions (Takada and Hiroshima) showed characteristic toxin profiles, with only OA detected in samples collected from Takada. In contrast, both OA and DTX1, in addition to a larger proportion of PTX2, were detected in D. acuminata from Hiroshima. D. fortii showed a toxin profile dominated by PTX2 although this species had higher levels of DTX1 than D. acuminata. OA was detected as a minor toxin in some D. fortii samples collected from Yakumo, Noheji, and Hakata. PTX2 was also the dominant toxin found among other Dinophysis species analyzed, such as D. norvegica, D. tripos, and D. caudata, although some pooled picked cells of these species contained trace levels of OA or DTX1. The results obtained in this study re-confirm that cellular toxin content and profiles are different even among strains of the same species.

DSP Toxin Distribution across Organs in Mice after Acute Oral Administration

“…The worldwide incidence of diarrheic shellfish toxins poses a threat to public health, with a consequent marine environment effect and great economic impact on the seafood industry [ 10 , 29 , 30 ]. In vivo toxicity differences were observed for the toxins of this group, both intraperitoneally [ 14 , 31 ] and orally [ 15 ].…”

An Artemia franciscana bioassay for the monitoring of lipophilic phycotoxins in marine bivalve mollusc cultures: An alternative to screening testing?

“…DSP phycotoxins are lipophilic substances that can contaminate shellfish meat (Uchida et al, 2018) and are produced by planktonic dinoflagellates belonging to the Dinophysis (D. acuta, D. acuminata, D. caudata, D. fortii, D. miles, D. norvegica, D. sacculus and D. tripos) and Phalacroma genera (P. mitra and P. rotundatum); as well as benthic species belonging to the Prorocentrum genus (P. lima, P. arenarium, P. belizeanum, P. concavum, P. faustiae, P. hoffmannianum, P. mild and P. maculosum) (Castro and Moser, 2012;Hallegraeff, 2003). In this regard, Souza et al (2016) analyzed the same hepatopancreas mussel samples collected in January and May 2014 assessed herein using the mouse bioassay and reported the presence of Dinophysis acuminata (120).…”

“…For example, Diarrheic Shellfish Poisoning (DSP) indicates a diarrheal syndrome which produces abdominal discomfort, nausea, vomiting and diarrhea (Grattan et al, 2016), caused by okadaic acid (AO) and derivatives such as the dinophysistoxin group (DTXs), yessotoxins (YTXs) and pectonotoxins (PTXs) (Castro and Moser, 2012;Barbieri, 2009;Hallegraeff, 2003). Okadaic acid (OA) and DTX toxins are lipophilic substances that can contaminate shellfish meat (Uchida et al, 2018) produced by planktonic dinoflagellates (Castro and Moser, 2012;Hallegraeff, 2003).…”

OMICs Approaches in Diarrhetic Shellfish Toxins Research

“…The knowledge obtained has been useful for instance to improve monitoring and forecast toxic microalgae outbreaks and also to predict new patterns of geographical distribution of DSTs in the context of climate change. The focus has been also the chemical characterization of the several toxin analogues (OA and DTXs), including the esterified forms accumulated by shellfish [ 12 , 13 ], and the development of more sensitive and portable instruments applied in environmental monitoring (e.g., development of biosensors) [ 14 , 15 ]. The toxicology of DSTs has been also investigated.…”