title: Effects of Heating on Proportions of Azaspiracids 1-10 in Mussels (Mytilus edulis) and Identification of Carboxylated Precursors for Azaspiracids 5, 10, 13, and 15.
abstract: Azaspiracids (AZAs) are marine biotoxins that induce human illness following the consumption of contaminated shellfish. European Union regulation stipulates that only raw shellfish are tested, yet shellfish are often cooked prior to consumption. Analysis of raw and heat-treated mussels (Mytilus edulis) naturally contaminated with AZAs revealed significant differences (up to 4.6-fold) in AZA1-3 (1-3) and 6 (6) values due to heat-induced chemical conversions. Consistent with previous studies, high levels of 3 and 6 were detected in some samples that were otherwise below the limit of quantitation before heating. Relative to 1, in heat-treated mussels the average (n = 40) levels of 3 (range, 11-502%) and 6 (range, 3-170%) were 62 and 31%, respectively. AZA4 (4) (range, <1-27%), AZA5 (5) (range, 1-21%), and AZA8 (8) (range, 1-27%) were each ∼5%, whereas AZA7 (7), AZA9 (9), and AZA10 (10) (range, <1-8%) were each under 1.5%. Levels of 5, 10, AZA13 (13), and AZA15 (15) increased after heating, leading to the identification of novel carboxylated AZA precursors in raw shellfish extracts, which were shown by deuterium labeling to be precursors for 5, 10, 13, and 15.
authors.affiliation: Marine Institute , Rinville, Oranmore, Co. Galway, Ireland.
authors.forename: Jane
authors.initials: J
authors.lastname: Kilcoyne
authors.affiliation: Measurement Science and Standards, National Research Council Canada , Halifax, Nova Scotia B3H 3Z1, Canada.
authors.forename: Pearse
authors.initials: P
authors.lastname: McCarron
authors.affiliation: Laboratoire Phycotoxines, Ifremer , Rue de l'Ile d'Yeu, 44311 Nantes, France.
authors.forename: Philipp
authors.initials: P
authors.lastname: Hess
authors.affiliation: Norwegian Veterinary Institute , P.O. Box 750 Sentrum, 0106 Oslo, Norway.
authors.forename: Christopher O
authors.initials: CO
authors.lastname: Miles
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D005506:Food Contamination / Q000032:analysis*; D006358:Hot Temperature; D008387:Marine Toxins / Q000032:analysis*; D013058:Mass Spectrometry; D012758:Shellfish / Q000032:analysis*; D013141:Spiro Compounds / Q000032:analysis*; D000095702:Polyether Toxins
chemical_list: D008387:Marine Toxins; D013141:Spiro Compounds; C406592:azaspiracid; D000095702:Polyether Toxins
keywords: azaspiracid; chemical conversion; decarboxylation; heating; hydroxylation; mass spectrometry; metabolism