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1.
Sci Total Environ ; 707: 136173, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31972913

RESUMO

Harmful algal blooms (HABs) that produce toxins and those that lead to fish kills are global problems that appear to be increasing in frequency and expanding in area. One way to help mitigate their impacts on people's health and livelihoods is to develop early-warning systems. Models to predict and manage HABs typically make use of complex multi-model structures incorporating satellite imagery and frequent monitoring data with different levels of detail into hydrodynamic models. These relatively more sophisticated methods are not necessarily applicable in countries like the Philippines. Empirical statistical models can be simpler alternatives that have also been successful for HAB forecasting of toxic blooms. Here, we present the use of the random forest, a machine learning algorithm, to develop an early-warning system for the prediction of two different types of HABs: fish kill and toxic bloom occurrences in Bolinao-Anda, Philippines, using data that can be obtained from in situ sensors. This site features intensive and extensive mariculture activities, as well as a long history of HABs. Data on temperature, salinity, dissolved oxygen, pH and chlorophyll from 2015 to 2017 were analyzed together with shellfish ban and fish kill occurrences. The random forest algorithm performed well: the fish kill and toxic bloom models were 96.1% and 97.8% accurate in predicting fish kill and shellfish ban occurrences, respectively. For both models, the most important predictive variable was a decrease in dissolved oxygen. Fish kills were more likely during higher salinity and temperature levels, whereas the toxic blooms occurred more at relatively lower salinity and higher chlorophyll conditions. This demonstrates a step towards integrating information from data that can be obtained through real-time sensors into a an early-warning system for two different types of HABs. Further testing of these models through times and different areas are recommended.


Assuntos
Peixes , Proliferação Nociva de Algas , Aprendizado de Máquina , Frutos do Mar , Animais , Aquicultura , Clorofila , Monitoramento Ambiental , Filipinas , Salinidade
2.
Environ Sci Technol ; 54(5): 2726-2733, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-31951385

RESUMO

Industrial release of mercury into the local Minamata environment with consequent poisoning of local communities through contaminated fish and shellfish consumption is considered the classic case of environmental mercury poisoning. However, the mercury species in the factory effluent has proved controversial, originally suggested as inorganic, and more recently as methylmercury species. We used newly available methods to re-examine the cerebellum of historic Cat 717, which was fed factory effluent mixed with food to confirm the source. Synchrotron high-energy-resolution fluorescence detection-X-ray absorption spectroscopy revealed sulfur-bound organometallic mercury with a minor ß-HgS phase. Density functional theory indicated energetic preference for α-mercuri-acetaldehyde as a waste product of aldehyde production. The consequences of this alternative species in the "classic" mercury poisoning should be re-evaluated.


Assuntos
Intoxicação do Sistema Nervoso por Mercúrio , Intoxicação por Mercúrio , Mercúrio , Compostos de Metilmercúrio , Animais , Gatos , Japão , Frutos do Mar
3.
J Agric Food Chem ; 68(5): 1427-1435, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31913622

RESUMO

A number of new C-11 hydroxyl metabolites (so-called M-toxins) of paralytic shellfish toxins (PSTs) have been discovered in contaminated shellfish, and trace amounts have also been detected in some strains of PST-producing microalgae. To investigate the chemical conversion and stability of M-toxins, mussel extracts were purified with solid-phase extraction cartridges (Oasis HLB) and Biogel P-2 resin columns and four partially purified M-toxin fractions were stored at different temperatures (-20, 4, and 20 °C) and pH values (3, 4, and 5). The concentrations and profiles of M-toxins in these fractions were analyzed using liquid chromatography coupled with tandem mass spectrometry for 27 weeks. Results further confirmed the chemical conversion pathway M1 → M3 → M5 and determined for the first time two new transformation pathways: M2 → M4 → M6 and neosaxitoxin (NEO) → M10. The half-lives of M1, M2, M4, and M10 were calculated using a first-order degradation kinetics model, which indicated that the degradation of all M-toxins was dependent upon the temperature and pH, increasing with rising temperature and pH. In comparison to M4 and M10, M1 was more sensitive to the temperature, followed by M2. Results suggest that M-toxins should be maintained at a low temperature (-20 °C) and low pH (3) for their prolonged storage. M-toxins were less stable than all of the common analogues of PSTs, which may be beneficial for shellfish to achieve rapid detoxification through transformation of PSTs to M-toxins. These new findings are of significance because they enable further understanding of the metabolism of PSTs and their detoxification mechanisms in contaminated shellfish.


Assuntos
Bivalves/química , Toxinas Marinhas/química , Frutos do Mar/toxicidade , Animais , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Concentração de Íons de Hidrogênio , Toxinas Marinhas/toxicidade , Estrutura Molecular , Frutos do Mar/análise , Espectrometria de Massas em Tandem , Temperatura Ambiente
4.
Mar Pollut Bull ; 150: 110778, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31910525

RESUMO

The aim of the present work was to unravel which environmental drivers govern the dynamics of toxic dinoflagellate abundance as well as their associated paralytic shellfish toxins (PSTs), diarrhetic shellfish toxins (DSTs) and pectenotoxin-2 (PTX2) in Ambon Bay, Eastern Indonesia. Weather, biological and physicochemical parameters were investigated weekly over a 7-month period. Both PSTs and PTX2 were detected at low levels, yet they persisted throughout the research. Meanwhile, DSTs were absent. A strong correlation was found between total particulate PST and Gymnodinium catenatum cell abundance, implying that this species was the main producer of this toxin. PTX2 was positively correlated with Dinophysis miles cell abundance. Vertical mixing, tidal elevation and irradiance attenuation were the main environmental factors that regulated both toxins and cell abundances, while nutrients showed only weak correlations. The present study indicates that dinoflagellate toxins form a potential environmental, economic and health risk in this Eastern Indonesian bay.


Assuntos
Dinoflagelados , Toxinas Marinhas , Baías , Monitoramento Ambiental , Indonésia , Frutos do Mar
5.
Artigo em Inglês | MEDLINE | ID: mdl-31638869

RESUMO

There are two official PSP detection methods (mouse bioassay and HLPC-FLD) and a number of alternative methods. Ethical considerations have led to regulations being adopted in some countries that limit or prohibit the application of mouse bioassay. Analytical methodologies (e.g. HPLC-FLD or LC-MSMS) have the disadvantages of not being able to detect new toxins or analogues or reflecting the overall toxicity of the sample. In addition, they require highly trained personnel and expensive equipment, which are not always available. In this work, we have evaluated a method based on the Neuro-2a cell-based assay to detect substances that inhibit voltage-dependent sodium channels (Manger's method). We tested PSP standards and natural samples contaminated with PSP. Here we demonstrate that the adapted Manger's method is suitable for calculating Toxicity Equivalency Factors (TEF) for STX-analogues. The method was shown to be useful for screening contaminated natural samples in concentrations above the regulatory limit for these toxins (80 µg STX equivalents/100 g shellfish). We were able to detect PSP in 19 natural mollusc samples from South Chile despite the presence of other marine toxins. These preliminary results suggest that the method could be used as a first step in screening programmes.


Assuntos
Análise de Alimentos , Contaminação de Alimentos/análise , Saxitoxina/análise , Saxitoxina/toxicidade , Alimentos Marinhos/análise , Alimentos Marinhos/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Chile , Relação Dose-Resposta a Droga , Camundongos , Frutos do Mar , Intoxicação por Frutos do Mar
6.
Anal Bioanal Chem ; 412(2): 397-411, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31797015

RESUMO

An analytical method for the simultaneous determination of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) in fish, shellfish and muscle of terrestrial animals was developed as an extension of a previously validated method for PBDE analysis. A single sample preparation based on QuEChERS-like extraction and a two-step clean-up, followed by a dual instrumental detection, was implemented. GC-MS/MS was used for PBDEs and LC-MS/MS for HBCDs. The method allows the quantification of fifteen PBDEs (28, 47, 49, 66, 77, 85, 99, 100, 138, 153, 154, 183, 197, 206, 209) and three HBCD isomers (α, ß and γ), reaching 10 pg/g LOQs for all the analytes except BDE 206 and 209 (100 pg/g LOQ). The validated method was applied to the analysis of 12 fish and shellfish species (sole, spiny dogfish, smooth-hound, mackerel, swordfish, grey mullet, cod, anchovy, red mullet, Atlantic horse mackerel, tuna fish and mussel) collected in central Italian markets accounting for a total of 44 samples. Generally, ΣPBDEs showed higher concentration than ΣHBCDs except in the case of mussels in which ΣHBCDs > ΣPBDEs. Cod and smooth-hound are the least contaminated species among those analysed in the present study, whereas the highest brominated flame retardant (BFR) levels were found in spiny dogfish samples. The measured contamination levels were generally comparable to or lower than those already published in European studies. Literature data for HBCDs in European fish and shellfish were hard to find; therefore, PBDE and HBCD levels were also compared with European Environmental Quality Standard (EQS) in biota (Directive 2013/39/EU). EQSs for HBCDs are six orders of magnitude higher than those for PBDEs; therefore, while no exceedance was observed for the first, almost all the samples analysed for PBDEs were above EQSs. The presented preliminary data on PBDEs and HBCDs are among the first published in marine fish and shellfish commercialised in Central Italy. Graphical abstrac.


Assuntos
Bromo/química , Cromatografia Líquida/métodos , Peixes , Retardadores de Chama/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Frutos do Mar , Animais
7.
Int J Food Microbiol ; 313: 108378, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31678817

RESUMO

Vibrio bacteria can accumulate in molluscan shellfish and cause human diseases. The United States (U.S.) has implemented Vibrio Control Plans to mitigate risks associated with these bacteria, which include time and temperature requirements for post-harvest processing and maintaining an unbroken cold chain. In this study, we tracked the performance of cold chains for U.S. farmed oysters distributed nationally and internationally using temperature sensors. Boxes and bags of oysters (n = 125) were shipped from farms in Washington State and the Chesapeake Bay to 143 unique businesses in 20 U.S. states, Washington D.C., and Hong Kong, China. Eighty-one percent of the temperature sensors were returned with usable data. The average product temperature among all participants was 4.4 ±â€¯2.7 °C (40 ±â€¯5 °F), which is 5.6 °C (10 °F) cooler than the 10 °C (50 °F) guidance criterium established by the U.S. government. There were spikes in temperature in some shipments: 18% of shipments (16/91) experienced oyster temperatures above 10 °C for one hour or more, and the median time spent out of temperature control was 2.5 h. We modeled V. parahaemolyticus abundance using temperature sensor data and 75% (68/91) of shipments had a net decrease in V. parahaemolyticus abundance in the cold chain. There are opportunities for improvements in cold chain performance in the shellfish industry and related businesses. In the discussion we provide recommendations for oyster producers related to product cooling, for businesses that handle shellfish, and for government and industry groups to develop guidance for shipping by air, among other issues.


Assuntos
Ostreidae/microbiologia , Frutos do Mar/microbiologia , Vibrio parahaemolyticus/crescimento & desenvolvimento , Animais , China , Temperatura Baixa , Contagem de Colônia Microbiana , Fazendas , Contaminação de Alimentos/análise , Manipulação de Alimentos , Humanos , Ostreidae/química , Ostreidae/crescimento & desenvolvimento , Refrigeração , Frutos do Mar/análise , Temperatura Ambiente , Estados Unidos
8.
Chemosphere ; 239: 124781, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31514006

RESUMO

Variation in arsenolipid concentrations was assessed in 18 seafood samples including fish, shellfish, and crustaceans purchased in Japan. Analyses were performed by high performance liquid chromatography-inductively coupled plasma mass spectrometry/electrospray ionization tandem mass spectrometry. Stable isotope ratios for nitrogen and carbon were also measured in the samples for obtaining trophic level information of the species. Arsenic-containing hydrocarbons (AsHCs) and arsenic-containing fatty acids (AsFAs) were detected in the seafood samples; the toxic AsHCs were found in all of the seafood samples with large variation in the concentrations (83 ±â€¯73 ng As/g fw, coefficient of variation = 88%). Our previous point estimate of health risk of AsHCs intake via seafood consumption in Japan, based on average AsHC concentration in seafood, suggested insignificant risk, and the present study supports our previous estimate. AsHC concentrations significantly correlated with lipid content of the seafood samples (r = 0.67, p < 0.01), a result expected because of the fat solubility of the compounds. The AsHCs concentrations, however, were not significantly correlated with nitrogen stable isotope ratios suggesting that AsHCs do not biomagnify. The source of the observed large variation in AsHC concentrations will be the subject of further investigation.


Assuntos
Arsênico/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Animais , Arsênico/química , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Graxos/análise , Ácidos Graxos/química , Peixes , Japão , Lipídeos/análise , Lipídeos/química , Isótopos de Nitrogênio/análise , Alimentos Marinhos/análise , Frutos do Mar/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
9.
J Sci Food Agric ; 100(1): 119-128, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31441054

RESUMO

BACKGROUND: T-2 toxin (T-2) is a potent mycotoxin and a common contaminant of aquatic animal feed, posing a serious risk to health and aquatic animals. We investigated the effect of T-2 on shrimp muscle proteins using proteomics and conventional biochemical methods. Shrimp were fed a diet containing T-2 at 0-12.2 mg kg-1 for 20 days, and changes to the muscle protein composition, ATPase activities, and the sulfhydryl (SH) content and hydrophobicity of actomyosin (AM) were determined. A proteomics study of the proteins was conducted with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), two-dimensional (2D) electrophoresis, and matrix-assisted laser desorption/ionization - time of flight mass spectrometry (MALDI-TOF/TOF MS). RESULTS: Exposure to T-2 markedly affected the muscle protein composition of shrimp in a concentration-responsive manner that displayed a diphasic effect. At a low T-2 concentration (1.2 mg kg-1 ), the levels of three major muscle proteins (myofibrillar, sarcoplasmic, and stroma) increased but at higher concentrations they declined progressively. T-2 exposure also led to a breakdown of muscle proteins as evidenced by increases in alkali-soluble protein and the surface hydrophobicity (SoANS) of AM. Thirty differentially expressed proteins were detected, 12 of which showed a concentration-response relationship with T-2 exposure. Among them, 11 homologous proteins were identified by mass spectrometry (MS), with several being key enzymes in energy metabolism. CONCLUSION: This study demonstrated that T-2 exposure at medium to high concentrations could significantly affect the protein composition and quality of shrimp muscle, and potentially some of its key metabolisms. One of the arginine kinases (spot 27) was particularly responsive to T-2 and could potentially be used as a biomarker protein for T-2 intoxication by shrimp. © 2019 Society of Chemical Industry.


Assuntos
Proteínas Musculares/química , Penaeidae/efeitos dos fármacos , Frutos do Mar/análise , Toxina T-2/toxicidade , Ração Animal/análise , Animais , Eletroforese em Gel de Poliacrilamida , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculos/química , Músculos/efeitos dos fármacos , Músculos/metabolismo , Penaeidae/química , Penaeidae/genética , Penaeidae/metabolismo , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
10.
Chemosphere ; 239: 124767, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518925

RESUMO

The present study analyzed the Peruvian scallop Argopecten purpuratus and its food sources for metal and fatty acid concentrations in order to determine spatial and temporal differences. Metals such as copper (Cu), manganese (Mn), and zinc (Zn) in gills and iron (Fe) and Zn in sediments were the most significant explaining factors for spatial differentiations (degree of contamination), while for fatty acids, it was C14:0, C15:0, C16:0 and C18:0 in A. purpuratus' muscle and in its food sources, which explained more temporal differences (El Niño-Southern Oscillation (ENSO) effect). Gills, digestive gland and intestine were the tissues where metal accumulation was the highest in A. purpuratus. Cd in digestive gland was always high, up to ∼250-fold higher than in other tissues, as previously reported in other bioindicator species for metal pollution. Fatty acids were good biomarkers when annual comparisons were performed, while metals when locations were compared. ENSO 2017 played an important role to disentangle A. purpuratus' biological conditions and food sources. A. purpuratus from Paracas locations mostly showed higher metal concentrations in gills and digestive glands, and lower fatty acid concentrations in muscle than those from Sechura and Illescas Reserved Zone.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Pectinidae/química , Poluentes Químicos da Água/análise , Animais , Aquicultura , Cobre/análise , Cobre/farmacocinética , Biomarcadores Ambientais , Ácidos Graxos/análise , Brânquias/química , Ferro/análise , Ferro/farmacocinética , Manganês/análise , Manganês/farmacocinética , Músculos/química , Pectinidae/metabolismo , Peru , Frutos do Mar/análise , Análise Espaço-Temporal , Distribuição Tecidual , Zinco/análise , Zinco/farmacocinética
11.
J Environ Radioact ; 211: 106043, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31557702

RESUMO

The activity concentrations of Polonium-210 (210Po) and Lead-210 (210Pb) were determined in shellfish (Perna canaliculus and Paphies subtriangulata) sampled bimonthly from March 2018 to February 2019 from 14 sites around New Zealand. Activity concentrations of 210Po ranged from 4.7 ±â€¯1.1 to 324 ±â€¯17 Bq. kg-1 with a mean value of 57 ±â€¯72 Bq. kg-1 (wet weight). The activity concentrations of 210Pb were lower than those for 210Po (0.1 ±â€¯0.4 and 1.9 ±â€¯0.4 Bq. kg-1, with a mean value of 0.7 ±â€¯0.4 Bq. kg-1, wet weight). The calculated 210Po/210Pb activity concentration ratios were higher than unity in all samples indicating that radionuclides are not in equilibrium in shellfish and most of the 210Po was unsupported by its grandparent 210Pb. No significant difference was noted in 210Po activity concentration between different seasons, species or shellfish condition index. Significant spatial variability in 210Po activity concentration was observed with elevated 210Po activity concentration in two sampling sites: Ninety Mile Beach (mean 257 ±â€¯47 Bq. kg-1) and Maunganui Bluff (mean 127 ±â€¯22 Bq. kg-1). Elevated 210Po is hypothesised to be related to an increase of 210Po accumulation through diet. Individuals who consume large quantities of shellfish (10 g per day or more) from areas affected by elevated 210Po activity concentration may be exposed to an annual committed effective dose from 210Po in shellfish in excess of 1 mSv.


Assuntos
Polônio , Radioisótopos de Chumbo , Nova Zelândia , Monitoramento de Radiação , Frutos do Mar
12.
Food Chem ; 310: 125947, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31841939

RESUMO

An ultra performance liquid chromatography-Triple time of flight mass spectrometry (UPLC-Triple TOF-MS/MS) method were established to characterize the lipid profiles in four shellfish species. More than 600 lipid molecular species belonging to 14 classes were detected. Phospholipids (PLs) were predominant in Chlamys farreri (54.9%) and glycerolipids (GLs) were dominant in Ostrea gigas (51.6%). PLs that contained polyunsaturated fatty acids (PUFAs) such as PC (16:0/20:5), PC (16:0/22:6) and PE (18:0/22:6) were the main molecular species. Especially, the percentage of sphingolipids (SLs) in four shellfishes is considerable (18.8-38.6%), the characterization of their special long-chain base (LCB) structure (mainly d19:3) and N-acyl group (mainly 16:0) was realized. Several SL subclasses with low abundance in four shellfish species, such as ceramide 2-aminoethylphosphonate (CAEP) and deoxy-ceramide (DeoxyCer), were also detected. These active lipids identified by this method have potential value in revealing the nutritional value of shellfishes and serving as biomarkers for distinguishing different shellfishes.


Assuntos
Cromatografia Líquida/métodos , Análise de Alimentos/métodos , Lipídeos/análise , Frutos do Mar/análise , Espectrometria de Massas em Tandem/métodos , Ácido Aminoetilfosfônico/análogos & derivados , Animais , Ceramidas , Ácidos Graxos Insaturados/análise , Lipídeos/química , Valor Nutritivo , Pectinidae/química , Fosfolipídeos/análise , Fosfolipídeos/química , Esfingolipídeos/análise
13.
Pol J Microbiol ; 68(4): 429-438, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31880887

RESUMO

Penaeus monodon is highly susceptible to vibriosis disease. Aims of the study were to identify the pathogen causing vibriosis in P. monodon through molecular techniques and develop a biocontrol method of the disease by application of herbal extracts. Shrimp samples were collected aseptically from the infected farm and the bacteria were isolated from the infected region of those samples. Based on phenotypic identification, several isolates were identified as Vibrio sp. 16S rRNA gene sequences of the selected isolates exhibited 100% homology with V. alginolyticus strain ATCC 17749. An in vivo infection challenge test was performed by immersion method with V. alginolyticus where these isolates caused high mortality in juvenile shrimp with prominent symptoms of hepatopancreatic necrosis. Antibiogram profile of the isolates was determined against eleven commercial antibiotic discs whereas the isolates were found resistant to multiple antibiotics. A total of twenty-one herbal extracts were screened where Emblica officinalis, Allium sativum, and Syzygium aromaticum strongly inhibited the growth of V. alginolyticus in in vitro conditions. In in vivo conditions, the ethyl acetate extracts of E. officinalis and A. sativum successfully controlled the vibriosis disease in shrimp at a dose of 10 mg/g feed. This is the first report on molecular identification and biocontrol of V. alginolyticus in shrimp in Bangladesh.Penaeus monodon is highly susceptible to vibriosis disease. Aims of the study were to identify the pathogen causing vibriosis in P. monodon through molecular techniques and develop a biocontrol method of the disease by application of herbal extracts. Shrimp samples were collected aseptically from the infected farm and the bacteria were isolated from the infected region of those samples. Based on phenotypic identification, several isolates were identified as Vibrio sp. 16S rRNA gene sequences of the selected isolates exhibited 100% homology with V. alginolyticus strain ATCC 17749. An in vivo infection challenge test was performed by immersion method with V. alginolyticus where these isolates caused high mortality in juvenile shrimp with prominent symptoms of hepatopancreatic necrosis. Antibiogram profile of the isolates was determined against eleven commercial antibiotic discs whereas the isolates were found resistant to multiple antibiotics. A total of twenty-one herbal extracts were screened where Emblica officinalis, Allium sativum, and Syzygium aromaticum strongly inhibited the growth of V. alginolyticus in in vitro conditions. In in vivo conditions, the ethyl acetate extracts of E. officinalis and A. sativum successfully controlled the vibriosis disease in shrimp at a dose of 10 mg/g feed. This is the first report on molecular identification and biocontrol of V. alginolyticus in shrimp in Bangladesh.


Assuntos
Conservantes de Alimentos/farmacologia , Penaeidae/microbiologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Frutos do Mar/microbiologia , Vibrio alginolyticus/efeitos dos fármacos , Vibrio alginolyticus/genética , Animais , Antibacterianos/farmacologia , DNA Bacteriano/genética , Conservação de Alimentos , Testes de Sensibilidade Microbiana , Penaeidae/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Vibrio alginolyticus/crescimento & desenvolvimento , Vibrio alginolyticus/isolamento & purificação
14.
Rev Sci Tech ; 38(2): 437-457, 2019 Sep.
Artigo em Inglês, Francês, Espanhol | MEDLINE | ID: mdl-31866683

RESUMO

The growth of aquaculture over the past 50 years has been accompanied by the emergence of aquatic animal diseases, many of which have spread to become pandemic in countries or continents. An analysis of 400 emerging disease events in aquatic animals that were logged by the Centre for Environment, Fisheries and Aquaculture Science between 2002 and 2017 revealed that more than half were caused by viruses. However, in molluscs, most events were parasitic. Categorising these events indicated that the key processes underpinning emergence were the movement of live animals and host switching. Profiles of key pathogens further illustrate the importance of wild aquatic animals as the source of new infections in farmed animals. It is also clear that the spread of new diseases through the largescale movement of aquatic animals for farming, for food and for the ornamental trade has allowed many to achieve pandemic status. Many viral pathogens of fish (e.g. infectious salmon anaemia, viral haemorrhagic septicaemia) and shrimp (e.g. white spot syndrome virus) affect a large proportion of the global production of key susceptible species. Wild aquatic animal populations have also been severely affected by pandemic diseases, best exemplified by Batrachochytrium dendrobatidis, a fungal infection of amphibians, whose emergence and spread were driven by the movement of animals for the ornamental trade. Batrachochytrium dendrobatidis is now widespread in the tropics and subtropics and has caused local extinctions of susceptible amphibian hosts. Given the rising demand for seafood, aquacultural production will continue to grow and diseases will continue to emerge. Some will inevitably achieve pandemic status, having significant impacts on production and trade, unless there are considerable changes in global monitoring and the response to aquatic animal diseases.


Assuntos
Anfíbios/microbiologia , Doenças dos Peixes/epidemiologia , Pandemias/veterinária , Frutos do Mar , Animais , Aquicultura , Quitridiomicetos , Micoses/microbiologia , Micoses/veterinária , Frutos do Mar/microbiologia , Frutos do Mar/parasitologia , Frutos do Mar/virologia
15.
J Agric Food Chem ; 67(46): 12918-12926, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31668066

RESUMO

The triosephosphate isomerase (TIM), Scy p 8, is a crab allergen and shows cross-reactivity in the shellfish. Here, recombinant Scy p 8 was expressed, and its crystal structure was determined at a resolution of 1.8 Å. The three-dimensional structure of Scy p 8 is primarily composed of a (ß/α)8-barrel motif prototype. Additionally, Scy p 8 showed cross-reactivity with high sequential and secondary structural identity among TIMs from shellfish species. The site-directed mutagenesis of critical amino acids of conformational epitopes was carried out, and the mutants of Trp 168 and Lys 237 to Ala reduced immunoglobulin E (IgE)-binding activity by approximately 30%, compared with wild-type TIM in an inhibition ELISA; however, it still induced basophil activation despite the interpatient variability between patients. These results can help to provide an accurate template for the analysis of the IgE binding and establish meaningful relationships between structure and allergenicity.


Assuntos
Braquiúros/enzimologia , Epitopos/química , Triose-Fosfato Isomerase/imunologia , Sequência de Aminoácidos , Animais , Braquiúros/química , Braquiúros/genética , Braquiúros/imunologia , Reações Cruzadas , Cristalização , Epitopos/genética , Epitopos/imunologia , Humanos , Imunoglobulina E/imunologia , Conformação Molecular , Conformação Proteica , Alinhamento de Sequência , Frutos do Mar/análise , Hipersensibilidade a Frutos do Mar/imunologia , Triose-Fosfato Isomerase/química , Triose-Fosfato Isomerase/genética
16.
Harmful Algae ; 89: 101654, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31672223

RESUMO

Dinoflagellate species of Dinophysis, in particular D. acuminata and D. acuta, produce lipophilic toxins that pose a threat to human health when concentrated in shellfish and jeopardize shellfish exploitations in western Europe. In northwestern Iberia, D. acuminata has a long growing season, from spring to early autumn, and populations develop as soon as shallow stratification forms when the upwelling season begins. In contrast, D. acuta blooms in late summer, when the depth of the pycnocline is maximal and upwelling pulses are moderate. In situ observations on the hydrodynamic regimes during the two windows of opportunity for Dinophysis species led us to hypothesize that D. acuta should be more sensitive to turbulence than D. acuminata. To test this hypothesis, we studied the response of D. acuminata and D. acuta to three realistic turbulence levels low (LT), ε ≈ 10-6 m2 s-3; medium (MT), ε ≈ 10-5 m2 s-3 and high (HT), ε ≈ 10-4 m2 s-3generated by Turbogen, a highly reproducible, computer-controlled system. Cells of both species exposed to LT and MT grew at rates similar to the controls. Marked differences were found in the response to HT: D. acuminata grew slowly after an initial lag phase, whereas D. acuta cell numbers declined. Results from this study support the hypothesis that turbulence may play a role in shaping the spatio-temporal distribution of individual species of Dinophysis. We also hypothesize that, in addition to cell disturbance affecting division, sustained high shear generated by microturbulence may cause a decline in Dinophysis numbers due to decreased densities of ciliate prey.


Assuntos
Cilióforos , Dinoflagelados , Europa (Continente) , Estações do Ano , Frutos do Mar
17.
Harmful Algae ; 88: 101659, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31582155

RESUMO

Paralytic shellfish poisoning (PSP) is a persistent problem that threatens human health and the availability of shellfish resources in Alaska. Regular outbreaks of marine dinoflagellates in the genus Alexandrium produce paralytic shellfish toxins (PSTs) that make shellfish consumption unsafe, and impose economic hardships on Alaska's shellfish industry. Phytoplankton and environmental monitoring spanning 2008-2016, and a pilot benthic cyst survey in 2016, were focused in the Juneau region of Southeast Alaska to investigate Alexandrium catenella distributions and conditions favorable to bloom development. Overwintering Alexandrium cysts were found in near-shore sediments throughout the study region. Alexandrium catenella cells were present in the water column across a range of sea surface temperatures (7-15 °C) and surface salinities (S = 4-30); however, an optimal temperature/salinity window (10-13 °C, 18-23) supported highest cell concentrations. Measurable levels of PSTs were associated with lower concentrations (100 cells L-1) of A. catenella, indicating high cell densities may not be required for shellfish toxicity to occur. Several interacting local factors were identified to support A. catenella blooms: 1) sea surface temperatures ≥7 °C; 2) increasing air temperature; 3) low to moderate freshwater discharge; and 4) several consecutive days of dry and calm weather. In combination, these bloom favorable conditions coincide with toxic bloom events during May and June in northern Southeast Alaska. These findings highlight how integrated environmental and phytoplankton monitoring can be used to enhance early warning capacity of toxic bloom events, providing more informed guidance to shellfish harvesters and resource managers in Alaska.


Assuntos
Dinoflagelados , Intoxicação por Frutos do Mar , Alaska , Estuários , Humanos , Frutos do Mar
18.
Harmful Algae ; 88: 101641, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31582160

RESUMO

Diarrhetic shellfish toxins (DSTs) are produced by the marine dinoflagellate, Dinophysis, as well as select species of benthic Prorocentrum. The DSTs can bioaccumulate in shellfish and cause gastrointestinal illness when humans consume high levels of this toxin. Although not routinely monitored throughout the U.S., recent studies in Washington, Texas, and New York suggest DSTs may be widespread throughout U.S. coastal waters. This study describes a four-year time series (2013-2016) of Dinophysis concentration and DST level in California mussels (Mytilus californianus) from Santa Cruz Municipal Wharf (SCMW) in Monterey Bay, California. Results show a maximum Dinophysis concentration of 9404 cells/L during this study and suggest Dinophysis persists as a member of the background phytoplankton community throughout the year. In California mussels, DSTs were found at persistent low levels throughout the course of this study, and exceeded the FDA guidance level of 160 ng/g 19 out of 192 weeks sampled. Concentrations of Dinophysis alone are a positive but weak predictor of DST level in California mussels, and basic environmental variables (temperature, salinity, and nutrients) do not sufficiently explain variation in Dinophysis concentration at SCMW. This study demonstrates that Dinophysis in Monterey Bay are producing DSTs that accumulate in local shellfish throughout the year, occasionally reaching levels of concern.


Assuntos
Dinoflagelados , Toxinas Marinhas , Mytilus , Animais , Baías , California , Humanos , Frutos do Mar , Washington
19.
Mar Pollut Bull ; 145: 1-4, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590765

RESUMO

The total mercury (T-Hg) and methylmercury (MeHg) concentrations in red snow crabs (Chionoecetes japonicus) caught off the coast of Japan were analyzed. The T-Hg concentration ranged from 0.03 to 0.56 mg/kg (mean: 0.21 mg/kg) in the raw muscle, and 0.02 to 0.74 mg/kg (mean: 0.27 mg/kg) in the boiled muscle. The MeHg concentration ranged from 0.04 to 0.54 mg/kg (mean: 0.20 mg/kg) in the raw muscle. The mean ratio of MeHg to T-Hg was 0.88. The crab body weight was found to significantly correlate with the concentrations of T-Hg (r = 0.488) and MeHg (r = 0.490) (p ≤ 0.01). For the general population in Japan, the intake of MeHg from eating red snow crab was estimated to be lower than 0.013 mg/week, which was less than one-sixth of the tolerable MeHg intake (0.08 mg/week).


Assuntos
Braquiúros/química , Mercúrio/análise , Compostos de Metilmercúrio/análise , Frutos do Mar/análise , Animais , Braquiúros/crescimento & desenvolvimento , Braquiúros/metabolismo , Qualidade de Produtos para o Consumidor , Contaminação de Alimentos/análise , Humanos , Japão , Mercúrio/metabolismo , Compostos de Metilmercúrio/metabolismo
20.
Mar Pollut Bull ; 145: 28-35, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590789

RESUMO

Native Americans face disproportionate exposures to environmental pollution through traditional subsistence practices including shellfish harvesting. In this study, the collection of butter clams (Saxidomus giganteus) was spatially and temporally paired with deployment of sediment pore water passive samplers at 20 locations in the Puget Sound region of the Salish Sea in the Pacific Northwest, USA, within adjudicated usual and accustomed tribal fishing grounds and stations. Clams and passive samplers were analyzed for 62 individual PAHs. A linear regression model was constructed to predict PAH concentrations in the edible fraction of butter clams from the freely dissolved fraction (Cfree) in porewater. PAH concentrations can be predicted within a factor of 1.9 ±â€¯0.2 on average from the freely dissolved PAH concentration in porewater using the following equation: PAHClam=4.1±0.1×PAHporewater This model offers a simplified, cost effective, and low impact approach to assess contaminant levels in butter clams which are an important traditional food.


Assuntos
Bivalves/química , Bivalves/efeitos dos fármacos , Contaminação de Alimentos/análise , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Frutos do Mar/análise , Poluentes Químicos da Água/farmacologia , Animais , Bivalves/crescimento & desenvolvimento , Qualidade de Produtos para o Consumidor , Monitoramento Ambiental , Humanos , Índios Norte-Americanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise
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