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Marine Toxins: Chemistry, Toxicity, Occurrence and Detection, with Special Reference to the Dutch Situation  [PDF]
Arjen Gerssen,Irene E. Pol-Hofstad,Marnix Poelman,Patrick P.J. Mulder,Hester J. Van den Top,Jacob De Boer
Toxins , 2010, DOI: 10.3390/toxins2040878
Abstract: Various species of algae can produce marine toxins under certain circumstances. These toxins can then accumulate in shellfish such as mussels, oysters and scallops. When these contaminated shellfish species are consumed severe intoxication can occur. The different types of syndromes that can occur after consumption of contaminated shellfish, the corresponding toxins and relevant legislation are discussed in this review. Amnesic Shellfish Poisoning (ASP), Paralytic Shellfish Poisoning (PSP), Diarrheic Shellfish Poisoning (DSP) and Azaspiracid Shellfish Poisoning (AZP) occur worldwide, Neurologic Shellfish Poisoning (NSP) is mainly limited to the USA and New Zealand while the toxins causing DSP and AZP occur most frequently in Europe. The latter two toxin groups are fat-soluble and can therefore also be classified as lipophilic marine toxins. A detailed overview of the official analytical methods used in the EU (mouse or rat bioassay) and the recently developed alternative methods for the lipophilic marine toxins is given. These alternative methods are based on functional assays, biochemical assays and chemical methods. From the literature it is clear that chemical methods offer the best potential to replace the animal tests that are still legislated worldwide. Finally, an overview is given of the situation of marine toxins in The Netherlands. The rat bioassay has been used for monitoring DSP and AZP toxins in The Netherlands since the 1970s. Nowadays, a combination of a chemical method and the rat bioassay is often used. In The Netherlands toxic events are mainly caused by DSP toxins, which have been found in Dutch shellfish for the first time in 1961, and have reoccurred at irregular intervals and in varying concentrations. From this review it is clear that considerable effort is being undertaken by various research groups to phase out the animal tests that are still used for the official routine monitoring programs.
Studies in the Use of Magnetic Microspheres for Immunoaffinity Extraction of Paralytic Shellfish Poisoning Toxins from Shellfish  [PDF]
Raymond Devlin,Katrina Campbell,Kentaro Kawatsu,Christopher Elliott
Toxins , 2011, DOI: 10.3390/toxins3010001
Abstract: Paralytic shellfish poisoning (PSP) is a potentially fatal human health condition caused by the consumption of shellfish containing high levels of PSP toxins. Toxin extraction from shellfish and from algal cultures for use as standards and analysis by alternative analytical monitoring methods to the mouse bioassay is extensive and laborious. This study investigated whether a selected MAb antibody could be coupled to a novel form of magnetic microsphere (hollow glass magnetic microspheres, brand name Ferrospheres-N) and whether these coated microspheres could be utilized in the extraction of low concentrations of the PSP toxin, STX, from potential extraction buffers and spiked mussel extracts. The feasibility of utilizing a mass of 25 mg of Ferrospheres-N, as a simple extraction procedure for STX from spiked sodium acetate buffer, spiked PBS buffer and spiked mussel extracts was determined. The effects of a range of toxin concentrations (20–300 ng/mL), incubation times and temperature on the capability of the immuno-capture of the STX from the spiked mussel extracts were investigated. Finally, the coated microspheres were tested to determine their efficiency at extracting PSP toxins from naturally contaminated mussel samples. Toxin recovery after each experiment was determined by HPLC analysis. This study on using a highly novel immunoaffinity based extraction procedure, using STX as a model, has indicated that it could be a convenient alternative to conventional extraction procedures used in toxin purification prior to sample analysis.
In Silico Analysis of Putative Paralytic Shellfish Poisoning Toxins Export Proteins in Cyanobacteria  [PDF]
Katia Soto-Liebe, Xaviera A. López-Cortés, Juan José Fuentes-Valdes, Karina Stucken, Fernando Gonzalez-Nilo, Mónica Vásquez
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0055664
Abstract: Paralytic shellfish poisoning toxins (PSTs) are a family of more than 30 natural alkaloids synthesized by dinoflagellates and cyanobacteria whose toxicity in animals is mediated by voltage-gated Na+ channel blocking. The export of PST analogues may be through SxtF and SxtM, two putative MATE (multidrug and toxic compound extrusion) family transporters encoded in PSTs biosynthetic gene cluster (sxt). sxtM is present in every sxt cluster analyzed; however, sxtF is only present in the Cylindrospermopsis-Raphidiopsis clade. These transporters are energetically coupled with an electrochemical gradient of proton (H+) or sodium (Na+) ions across membranes. Because the functional role of PSTs remains unknown and methods for genetic manipulation in PST-producing organisms have not yet been developed, protein structure analyses will allow us to understand their function. By analyzing the sxt cluster of eight PST-producing cyanobacteria, we found no correlation between the presence of sxtF or sxtM and a specific PSTs profile. Phylogenetic analyses of SxtF/M showed a high conservation of SxtF in the Cylindrospermopsis-Raphidiopsis clade, suggesting conserved substrate affinity. Two domains involved in Na+ and drug recognition from NorM proteins (MATE family) of Vibrio parahaemolyticus and V. cholerae are present in SxtF/M. The Na+ recognition domain was conserved in both SxtF/M, indicating that Na+ can maintain the role as a cation anti-transporter. Consensus motifs for toxin binding differed between SxtF and SxtM implying differential substrate binding. Through protein modeling and docking analysis, we found that there is no marked affinity between the recognition domain and a specific PST analogue. This agrees with our previous results of PST export in R. brookii D9, where we observed that the response to Na+ incubation was similar to different analogues. These results reassert the hypothesis regarding the involvement of Na+ in toxin export, as well as the motifs L398XGLQD403 (SxtM) and L390VGLRD395 (SxtF) in toxin recognition.
OCCURRENCE OF TETRODOTOXIN AND PARALYTIC SHELLFISH TOXINS IN Phallusia nigra (TUNICATA, ASCIDIACEA) FROM THE BRAZILIAN COAST
FREITAS, J. C.;OGATA, T.;VEIT, C.H.;KODAMA, M.;
Journal of Venomous Animals and Toxins , 1996, DOI: 10.1590/S0104-79301996000100004
Abstract: we have already shown the presence of guanidine neurotoxins in calcareous red algae and mussels collected in the s?o sebasti?o channel (state of s?o paulo, brazil). it is known that these neurotoxins comprise more than 25 analogues such as tetrodotoxin (ttx) and derivatives plus the paralytic shellfish toxins (pst) found in a variety of marine, freshwater and amphibious species. filter feeding animals generally possess large amounts of these neurotoxins. the tunicates are sessil marine animals with a high rate of sea water filtration. the tunics and siphons of 50 specimens of phallusia nigra were dissected and the visceral organs were immersed in methanol containing acetic acid 0.02 n ph 5.0. the extract was prepared by homogenization, filtration and the methanolic phase was concentrated under reduced pressure and defatted with chloroform. the polar phase was evaporated and the residue dissolved in deionized water for further purification in ionic-exchange resin column (bio-gel p-2) and hplc analysis. the extract showed paralytic effects on mouse assay (26.9 mu/100mg) and on crustacean isolated nerve preparations. the chemical analysis for ttx and pst revealed toxins with retention times similar to gonyautoxins, saxitoxins and ttx. these findings are important to explain future toxin envenoming outbreaks on the brazilian coast.
Paralytic shellfish toxins in shellfish from the coast of high frequent harmful algae blooms occurrence areas in East China Sea and South China Sea
中国东海和南海有害赤潮高发区麻痹性贝毒素研究

JIANG Tianjiu,CHEN Jufeng,ZOU Yinlin,LIU Jiesheng,YANG Weidong,
江天久
,陈菊芳,邹迎麟,刘洁生,杨维东

应用生态学报 , 2003,
Abstract: The paralytic shellfish poisoning (PSP) toxicity levels of shellfish collected from shellfish growing zones in Zhoushan areas of East China Sea and Shenzhen areas of South China Sea during January-November 2002 were determined with AOAC bioassay method. The results showed that the toxicity levels of shellfish from Zhoushan were very low,and few shellfish samples could be detected the PSP toxicities.The same levels appeared in the shellfish from Shenzhen, but the percentage of shellfish samples contaminated PSP was up to 30%, and the scallop Chalmys nobilis was dominated in the contaminated shellfish species.Analyses on the toxic profiles of digest gland and edible tissue extraction of scallop from Shenzhen showed that a similar suite of toxins presented in the gland and edible tissues.The high potency neoSTX and low potency GTX 5 had a high proportions, up to 60.8% and 11.4%,respectively in the tissue, and the high potency GTX 1+2 and GTX 5 were the dominant toxins, up to 38.9% and 20%,respectively in the gland. Most of the toxin were accumulated in ingested gland of scallop,and the toxic content in gland was about 8 folds more than that in the edible tissues.
Paralytic shellfish toxins in the chocolata clam, Megapitaria squalida (Bivalvia: Veneridae), in Bahía de La Paz, Gulf of California
Gárate-Lizárraga,I; Bustillos-Guzmán,J.J; Erler,K; Mu?etón-Gómez,M.S; Luckas,B; Tripp-Quezada,A;
Revista de Biología Tropical , 2004,
Abstract: occurrence and toxic profiles of paralytic shellfish toxins (pst) in the chocolata clam megapitaria squalida were investigated. from december 2001 to december 2002, 25 clams were obtained monthly from bahía de la paz, gulf of california. additionally, net (20 μm) and bottle phytoplankton samples were also collected to identify toxic species. toxins were analyzed by hplc with post-column oxidation and fluorescence detection. toxicity in the clam was low and varied from 0.14 to 5.46 μg/stxeq/100 g. toxicity was detected in december, march, april, june, and august. toxin profile was composed mainly by stx, gtx2, gtx3, dcgtx2, dcgtx3, c2, dcstx and b1. gymnodinium catenatum was the only pst-producing dinoflagellate identified in the phytoplankton samples throughout the study period. g. catenatum was observed mainly in net samples from december 2001 to december 2002; however, in bottle samples, g. catenatum was only observed in five months. highest abundance (2 600 cells l-1 ) was observed in march and the lowest (160 cells l-1 ) in june. g. catenatum mainly formed two-cell chains and rarely four or eight. the presence of pst in net phytoplankton samples support the fact that g. catenatum is the main source of pst in the clams. this study represents the first report of pst toxins in the chocolata clam from bahía de la paz
Simultaneous presence of Paralytic and Diarrheic Shellfish Poisoning toxins in Mytilus chilensis samples collected in the Chiloe Island, Austral Chilean Fjords
GARCíA,CARLOS; MARDONES,PAMELA; SFEIR,ANDREA; LAGOS,NéSTOR;
Biological Research , 2004, DOI: 10.4067/S0716-97602004000500002
Abstract: the study shown here provides the first indisputable evidence that shellfish can be contaminated with paralytic shellfish poisoning (psp) and diarrheic shellfish poisoning (dsp) toxins during the summer season in the southern chilean fjords. quantitative analysis of the simultaneous presence of psp and dsp toxins in mytilus chilensis samples collected in the chiloe island are shown. the high performance liquid chromatography (hplc) analysis with pre-column derivatization method for dsp toxins and the post-column derivatization methods for psp toxins, both with fluorescent on-line detections, showed that both type of toxins were concentrated by the filter bivalve mytilus chilensis in amounts above the international safe limits. the phytoplankton analysis showed the presence of both alexandrium catenella and dinophysis acuta in the water column. the data shows stratification of the toxic dinoflagellates in the water column, since the lowest amount of both dsp and psp toxins were measured in the superficial and deeper levels of the water column. moreover, the highest toxicities of both types of toxins were shown by the shellfish samples collected at a depth of 6 meters with 190 nanograms of dtx-1 / gram of digestive gland and 709.8 mg of psp toxins / 100 grams of mussel meat.
Simultaneous presence of Paralytic and Diarrheic Shellfish Poisoning toxins in Mytilus chilensis samples collected in the Chiloe Island, Austral Chilean Fjords  [cached]
CARLOS GARCíA,PAMELA MARDONES,ANDREA SFEIR,NéSTOR LAGOS
Biological Research , 2004,
Abstract: The study shown here provides the first indisputable evidence that shellfish can be contaminated with Paralytic Shellfish Poisoning (PSP) and Diarrheic Shellfish Poisoning (DSP) toxins during the summer season in the Southern Chilean fjords. Quantitative analysis of the simultaneous presence of PSP and DSP toxins in Mytilus chilensis samples collected in the Chiloe Island are shown. The High Performance Liquid Chromatography (HPLC) analysis with pre-column derivatization method for DSP toxins and the post-column derivatization methods for PSP toxins, both with fluorescent on-line detections, showed that both type of toxins were concentrated by the filter bivalve Mytilus chilensis in amounts above the international safe limits. The phytoplankton analysis showed the presence of both Alexandrium catenella and Dinophysis acuta in the water column. The data shows stratification of the toxic dinoflagellates in the water column, since the lowest amount of both DSP and PSP toxins were measured in the superficial and deeper levels of the water column. Moreover, the highest toxicities of both types of toxins were shown by the shellfish samples collected at a depth of 6 meters with 190 nanograms of DTX-1 / gram of digestive gland and 709.8 mg of PSP toxins / 100 grams of mussel meat.
PRESENCE OF P.S.P. TOXINS (PARALYTIC SHELLFISH POISON) IN MUSSELS OF SARDINIA AND NON-CONFORMITY MANAGEMENT  [cached]
S. Virgilio,G. Lorenzoni,E. Marongiu,T. Tedde
Italian Journal of Food Safety , 2013, DOI: 10.4081/ijfs.2010.8.71
Abstract: The progressive diffusion of dinoflagellates belonging to Alexandrium genus (A. catenella and A.minutun) and the contamination of the mussels used usually as food with marine toxins represents an high risk for the human health and for business mussels farms. In this study, the authors reported results of analysis during 2008 for detection P.S.P. (Paralytic Shellfish Poison) toxins in mussels bred in Olbia and Oristano areas and health precautions.
Paralytic shellfish toxins in the chocolata clam, Megapitaria squalida (Bivalvia: Veneridae), in Bahía de La Paz, Gulf of California  [cached]
I Gárate-Lizárraga,J.J Bustillos-Guzmán,K Erler,M.S Mu?etón-Gómez
Revista de Biología Tropical , 2004,
Abstract: Occurrence and toxic profiles of paralytic shellfish toxins (PST) in the chocolata clam Megapitaria squalida were investigated. From December 2001 to December 2002, 25 clams were obtained monthly from Bahía de La Paz, Gulf of California. Additionally, net (20 μm) and bottle phytoplankton samples were also collected to identify toxic species. Toxins were analyzed by HPLC with post-column oxidation and fluorescence detection. Toxicity in the clam was low and varied from 0.14 to 5.46 μg/STXeq/100 g. Toxicity was detected in December, March, April, June, and August. Toxin profile was composed mainly by STX, GTX2, GTX3, dcGTX2, dcGTX3, C2, dcSTX and B1. Gymnodinium catenatum was the only PST-producing dinoflagellate identified in the phytoplankton samples throughout the study period. G. catenatum was observed mainly in net samples from December 2001 to December 2002; however, in bottle samples, G. catenatum was only observed in five months. Highest abundance (2 600 cells l-1 ) was observed in March and the lowest (160 cells l-1 ) in June. G. catenatum mainly formed two-cell chains and rarely four or eight. The presence of PST in net phytoplankton samples support the fact that G. catenatum is the main source of PST in the clams. This study represents the first report of PST toxins in the chocolata clam from Bahía de La Paz Se investigó la ocurrencia así como los perfiles de toxinas paralíticas (PST) en la almeja chocolata Megapitaria squalida (Sowerby, 1835), de la cual se recolectaron mensualmente 25 ejemplares de diciembre del 2001 a diciembre del 2000 en La Bahía de La Paz, Golfo de California. Simultáneamente, se obtuvieron muestras de fitoplancton de botella y de red (20 μM) para identificar especies tóxicas, así como para detectar la presencia de toxinas paralíticas. Las toxinas se analizaron por HPLC con una oxidación post-columna y detección fluorescente. La toxicidad en las almejas fue baja y varió de 0.14 a 5.46 μg/STXeq/100 g y se detectó en diciembre, marzo, abril, junio y agosto. El perfil de toxinas estuvo compuesto principalmente por STX, GTX2, GTX3, dcGTX2, dcGTX3, C2, dcSTX y B1, siendo similar al perfil observado en las muestras de red. Gymnodinium catenatum fue la única especie productora de toxinas paralíticas identificada en las muestras de fitoplancton a través de todo el período del estudio. G. catenatum se observó principalmente en muestras de red correspondientes a diciembre 2001-diciembre 2002; sin embargo, en muestras de botella, G. Catenatum solo fue observado en cinco meses. La abundancia más alta (2 600 céls l-1 ) se encontró en
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