title: In vitro bioaccessibility of the marine biotoxins okadaic acid, dinophysistoxin-2 and their 7-O-acyl fatty acid ester derivatives in raw and steamed shellfish.
abstract: Okadaic acid (OA), Dinophysistoxins (DTX1 and DTX2) and their acyl-derivatives (DTX3) are marine toxins responsible for the human diarrhetic shellfish poisoning. To date the amount of toxins ingested from consumption of shellfish has been considered equal to the amount of toxins available for uptake by the human body. The aim of this study is to assess the OA, DTX2 and DTX3 fractions released from raw and steamed mussels and cockles into the digestive fluids (bioaccessibility) using a static in vitro digestion model. Higher bioaccessibility was found in mussels (86 ± 4%) than in cockles (59 ± 9%). A significant reduction of ester derivatives of OA and an increase of OA were observed in the bioaccessible fraction of mussel samples, suggesting that DTX3 undergo conversion into their more toxic parent compounds during human digestion. However, similar increase of DTX2 and reduction of the respective acyl derivatives was not observed. Steaming lead to significant reduction of OA and analogues bioaccessibility in both species even though increased concentrations of toxins are obtained after this treatment. Risk assessment based solely on DSP toxins occurrence in seafood can conduct to an overestimation of the exposure and lead to more conservative regulatory measures.
authors.affiliation: IPMA - Portuguese Institute of the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal; Faculty of Veterinary Medicine, University of Lisbon, Av. da Universidade Técnica, 1300-477 Lisbon, Portugal.
authors.forename: Diana
authors.initials: D
authors.lastname: Manita
authors.affiliation: IPMA - Portuguese Institute of the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal.
authors.forename: Ricardo N
authors.initials: RN
authors.lastname: Alves
authors.affiliation: IPMA - Portuguese Institute of the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal.
authors.forename: Ana Catarina
authors.initials: AC
authors.lastname: Braga
authors.affiliation: IPMA - Portuguese Institute of the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal; Empresa Brasileira de Pesquisa Agropecuária, Embrapa Meio-Norte, Ministério da Agricultura, Pecuária e Abastecimento, BR 343 km 35 CP 341, CEP 64200-970, Parnaíba, Brazil.
authors.forename: Fabiola H S
authors.initials: FHS
authors.lastname: Fogaça
authors.affiliation: IPMA - Portuguese Institute of the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal; CIIMAR - Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal.
authors.forename: António
authors.initials: A
authors.lastname: Marques
authors.affiliation: IPMA - Portuguese Institute of the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal; CCMAR - Centre of Marine Sciences, University of Algarve, Campus of Gambelas, 8005-139 Faro, Portugal. Electronic address: prcosta@ipma.pt.
authors.forename: Pedro Reis
authors.initials: PR
authors.lastname: Costa
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000187:drug effects*; D002273:Carcinogens / Q000493:pharmacokinetics; D002853:Chromatography, Liquid / Q000379:methods; D004952:Esters / Q000737:chemistry; D005227:Fatty Acids / Q000737:chemistry; D006801:Humans; D066298:In Vitro Techniques; D008387:Marine Toxins / Q000493:pharmacokinetics*; D013058:Mass Spectrometry / Q000379:methods; D019319:Okadaic Acid / Q000493:pharmacokinetics* / Q000031:analogs & derivatives; D011714:Pyrans / Q000493:pharmacokinetics*; D012758:Shellfish / Q000032:analysis*; D013227:Steam
chemical_list: D002273:Carcinogens; D004952:Esters; D005227:Fatty Acids; D008387:Marine Toxins; D011714:Pyrans; D013227:Steam; D019319:Okadaic Acid; C076221:dinophysistoxin 2
keywords: Diarrhetic shellfish poisoning; Dinophysis; Lipophilic toxins; Okadaic acid