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1.
Toxicon ; 174: 48-56, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31989929

RESUMO

Paralytic shellfish poisoning is a human intoxication syndrome associated with the consumption of seafood that has been contaminated with paralytic shellfish toxins (PSTs), a group of natural neurotoxic alkaloids produced by marine dinoflagellates, including some Alexandrium species. This study presents findings of PSTs in mussels (Mytilus galloprovincialis) during 2018-2019 in several mollusc production areas of Sardinia (Italy, western Mediterranean). Investigations of the presence and abundance of PST-producing microalgal species in marine water and of the toxins associated with shellfish were carried out concomitantly. Overall, the results suggested a spatio-temporal expansion of Alexandriumpacificum and Alexandriumminutum in recent years, with an increasing number of PSTs present in molluscs and increased occurrences of toxicity cases. Liquid chromatography with fluorescence detection determined the toxin profile to be composed primarily of the carbamate gonyautoxin-5 and N-sulphocarbamoyltoxins 1 and 2. The study highlights the potential high risk to consumers of poisoning by bivalve molluscs bred in Sardinia, where shellfish production is a very important industrial sector. For this reason, routine monitoring is strongly recommended in order to mitigate any harm to human health as well as negative socio-economic consequences.

2.
Artigo em Inglês | MEDLINE | ID: mdl-30882280

RESUMO

Microalgal species growing in marine and aquaculture environments can be responsible for harmful events because of their ability to produce potent natural toxins that can accumulate in edible mollusc species. Their consumption can cause severe illness and even be lethal. The European Union provides comprehensive regulations covering various general food safety aspects to manage the risk of contamination in shellfish farms. Many analytical methods have been proposed to evaluate algal toxins presence in the environment and in food products, for conducting surveillance studies of the main molluscs production sites and, where necessary, immediate monitoring of possible contamination of shellfish. In this work, a one-year analytical surveillance study was carried out to verify the possible presence of algal biotoxins in molluscs from a Mediterranean breeding area. Water and molluscs were sampled from a district of the North-East coast of Sicily, consisting of a unique brackish ecosystem of two lakes connected to each other and to the sea by narrow canals. Water samples were collected to investigate phytoplankton i by microscope analysis to assess the presence of potentially toxin-producing species, such as Pseudo-nitzschia spp, Alexandrium spp and Gonyaulax spinifera, although the presence of toxic phytoplankton has never reached alert levels. Mussels and clams samples were submitted to analysis of paralytic shellfish poisoning toxins, amnesic shellfish poisoning toxins and lipophilic toxins by liquid chromatography-based methods Only a few yessotoxins were detected, having concentrations always below the regulation limits. An existing liquid chromatography-tandem mass spectrometry-based multiresidue method for lipophilic biotoxins was adopted and extended to cover emerging biotoxins such as cyclic imines. The performance of the analytical method for Gymnodimine A and Spirolide 13-desMeC was assessed, obtaining respective quantitation limits of 20 and 10 µg kg-1, a precision always lower than 13% and trueness in the 81-120% range. Method applicability was confirmed using certified materials and a naturally contaminated sample.


Assuntos
Monitoramento Ambiental , Inocuidade dos Alimentos , Toxinas Marinhas/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Animais , Análise de Alimentos , Itália , Região do Mediterrâneo , Frutos do Mar
3.
Mar Pollut Bull ; 147: 117-132, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29295741

RESUMO

An inventory of phytoplankton diversity in 12 Adriatic ports was performed with the port baseline survey. Particular emphasis was put on the detection of harmful aquatic organisms and pathogens (HAOP) because of their negative impact on ecosystem, human health, and the economy. Phytoplanktonic HAOP are identified as species, either native or non-indigenous (NIS), which can trigger harmful algal blooms (HAB). A list of 691 taxa was prepared, and among them 52 were classified as HAB and five as NIS. Records of toxigenic NIS (Pseudo-nitzschia multistriata, Ostreopsis species including O. cf. ovata) indicate that the intrusion of non-native invasive phytoplankton species has already occurred in some Adriatic ports. The seasonal occurrence and abundance of HAOP offers a solid baseline for a monitoring design in ports in order to prevent ballast water uptake and possible expansion of HAOP outside their native region.


Assuntos
Proliferação Nociva de Algas , Fitoplâncton , Biodiversidade , Diatomáceas , Dinoflagelados , Ecossistema , Espécies Introduzidas , Mar Mediterrâneo , Inquéritos e Questionários
4.
Mar Drugs ; 10(1): 140-62, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22363227

RESUMO

The Northern Adriatic Sea is the area of the Mediterranean Sea where eutrophication and episodes related to harmful algae have occurred most frequently since the 1970s. In this area, which is highly exploited for mollusk farming, the first occurrence of human intoxication due to shellfish consumption occurred in 1989, nearly 10 years later than other countries in Europe and worldwide that had faced similar problems. Until 1997, Adriatic mollusks had been found to be contaminated mostly by diarrhetic shellfish poisoning toxins (i.e., okadaic acid and dinophysistoxins) that, along with paralytic shellfish poisoning toxins (i.e., saxitoxins), constitute the most common marine biotoxins. Only once, in 1994, a toxic outbreak was related to the occurrence of paralytic shellfish poisoning toxins in the Adriatic coastal waters. Moreover, in the past 15 years, the Adriatic Sea has been characterized by the presence of toxic or potentially toxic algae, not highly widespread outside Europe, such as species producing yessotoxins (i.e., Protoceratium reticulatum, Gonyaulax spinifera and Lingulodinium polyedrum), recurrent blooms of the potentially ichthyotoxic species Fibrocapsa japonica and, recently, by blooms of palytoxin-like producing species of the Ostreopsis genus. This review is aimed at integrating monitoring data on toxin spectra and levels in mussels farmed along the coast of the Emilia-Romagna region with laboratory studies performed on the species involved in the production of those toxins; toxicity studies on toxic or potentially toxic species that have recently appeared in this area are also reviewed. Overall, reviewed data are related to: (i) the yessotoxins producing species P. reticulatum, G. spinifera and L. polyedrum, highlighting genetic and toxic characteristics; (ii) Adriatic strains of Alexandrium minutum, Alexandrium ostenfeldii and Prorocentrum lima whose toxic profiles are compared with those of strains of different geographic origins; (iii) F. japonica and Ostreopsis cf. ovata toxicity. Moreover, new data concerning domoic acid production by a Pseudo-nitzschia multistriata strain, toxicity investigations on a Prorocentrum cf. levis, and on presumably ichthyotoxic species, Heterosigma akashiwo and Chattonella cf. subsalsa, are also reported.


Assuntos
Toxinas Marinhas/análise , Microalgas/química , Aerossóis , Animais , Aquicultura , Bivalves/química , Ecossistema , Humanos , Mar Mediterrâneo , Microalgas/crescimento & desenvolvimento , Microalgas/patogenicidade , Ácido Okadáico/análise , Oxocinas/análise , Saxitoxina/análise , Frutos do Mar/análise , Fatores de Tempo
5.
Toxicon ; 55(2-3): 280-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19660488

RESUMO

This paper reports on the determination of toxin profile of mussels (Mytilus galloprovincialis) collected in November-December 2003 along the Emilia Romagna coasts (Italy) when a high concentration of Alexandrium ostenfeldii cells was detected in seawater. Detailed liquid chromatography-mass spectrometry (LC-MS) analyses were performed on the crude extracts in both selected ion monitoring (SIM) and multiple reaction monitoring (MRM) modes. They revealed that M. galloprovincialis had accumulated the three major spirolides produced by the alga, namely 13-desMethyl spirolide C, 13,19-didesMethyl spirolide C and 27-hydroxy-13,19-didesMethyl spirolide C, which fully accounted for toxicity of lipophilic extracts shown in mouse bioassay. Interestingly, yessotoxin (YTX) and its analogues were still present in mussel polar extracts but YTX itself was not the major toxin contained in mussels. The presence of pectenotoxin-2 seco acid (PTX-2sa) and its putative epimer was also assessed. The presence of azaspiracids, never reported from the Adriatic sea, as well as of diarrhetic shellfish poisoning toxins (okadaic acid, dinophysistoxins and OA esters) and domoic acid, long known as contaminants of Adriatic mussels, was also investigated.


Assuntos
Toxinas Marinhas/química , Toxinas Marinhas/toxicidade , Mytilus/química , Animais , Cromatografia Líquida de Alta Pressão , Eutrofização , Furanos/química , Furanos/toxicidade , Hidrólise , Indicadores e Reagentes , Itália , Espectrometria de Massas , Mar Mediterrâneo , Camundongos , Ácido Okadáico/química , Ácido Okadáico/toxicidade , Oxocinas/química , Oxocinas/toxicidade , Fitoplâncton/química , Piranos/química , Piranos/toxicidade , Estações do Ano , Solventes , Compostos de Espiro/química , Compostos de Espiro/toxicidade
6.
Toxicon ; 47(5): 597-604, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16564060

RESUMO

This paper reports on the first occurrence of fairly high numbers of Alexandrium ostenfeldii along the Emilia Romagna coasts (Italy). Detailed liquid chromatography-mass spectrometry (LC-MS) analyses of the toxin profile were performed on a strain of the organism collected in November 2003, isolated during the event and grown in culture. Selected ion monitoring (SIM) and multiple reaction monitoring (MRM) experiments were carried out for detection of spirolides and paralytic shellfish poisoning (PSP) toxins. They revealed that the Adriatic A. ostenfeldii produces mainly spirolide 13-desmethyl C at levels of 3.7 pg/cell but not PSP toxins. Interestingly, low levels of some spirolide isomers that have not been reported so far in other strains of the dinoflagellate were also detected. This represents the first report of spirolide-type toxins in the Adriatic Sea.


Assuntos
Dinoflagelados/química , Dinoflagelados/isolamento & purificação , Toxinas Marinhas/análise , Toxinas Marinhas/química , Animais , Cromatografia Líquida , Itália , Lactonas/química , Espectrometria de Massas , Oceanos e Mares , Água do Mar/química
7.
Sci Total Environ ; 353(1-3): 218-31, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16257435

RESUMO

The temporal dynamics of microphytoplankton, microzooplankton and mesozooplankton were monitored over 37 months in the Adriatic Sea in order to identify alterations in the plankton structures, which can lead to, or enhance the production of macro-aggregates, that affected the entire northern basin in summers 2000 and 2002, and to assess any negative effects of mucilage on plankton temporal patterns. Samples were collected monthly, from June 1999 to July 2002, on three transects at 9 stations across the northern and central Adriatic Sea. Besides the high year-to-year variations in abundances and taxonomical composition, plankton communities only showed a clear seasonal succession during 2001, when since April a grazing food web developed and was able to control large sized phytoplankton increase. In spring-summer 2000 and 2002 consumer abundances remained quite low and the dominant mesozooplankton summer species (Penilia avirostris) did not reach its usual summer maximum. The lack of an efficient top control was more evident on the northernmost transect, where generally grazing food web prevails over the microbial one. A large part of the microphytoplankton blooms, although not particularly intense, was exported to the bottom in the particulate phase, where it was processed by bacteria, enhancing the production of refractory dissolved material.


Assuntos
Ecossistema , Eucariotos/fisiologia , Cadeia Alimentar , Biologia Marinha/estatística & dados numéricos , Fitoplâncton/fisiologia , Zooplâncton/fisiologia , Animais , Mar Mediterrâneo , Dinâmica Populacional , Estações do Ano
8.
Sci Total Environ ; 353(1-3): 307-16, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16289296

RESUMO

Oceanographic cruises were carried out monthly from June 1999 to July 2002 to follow the mucilage formation process in the Northern Adriatic Sea. Results show that in correspondence with these events the dinoflagellate Gonyaulax fragilis (Schütt) Kofoid was observed both in the water column and within mucilage aggregates. In the water column, increasing abundances were observed from May until July, with values never exceeding 8500 cells l(-1). Much higher densities were observed within superficial gelatinous aggregates (22800-3400000 cells l(-1)). In mucilage samples, a large number of decomposing cells were present, together with abundant alive cells, enveloped in exudates. G. fragilis isolated from mucilage samples was cultured in three different culture media; it was characterized by a low growth rate but it produced a high amount of polysaccharides. The highest yield both in terms of cell number and carbohydrate production was observed in the medium having the highest nitrogen and phosphorus content and the lowest N/P ratio. The monomeric composition of G. fragilis carbohydrates, compared with that of mucilage samples, showed that in both natural and cultured samples galactose was the most abundant sugar; in addition, an overall good correlation, especially between the monomeric carbohydrate composition of G. fragilis grown in f/2 medium and that of a mucilage sample in which this species was present in high density, was observed.


Assuntos
Dinoflagelados/crescimento & desenvolvimento , Ecossistema , Biologia Marinha/estatística & dados numéricos , Água do Mar/parasitologia , Zooplâncton/crescimento & desenvolvimento , Animais , Dinoflagelados/química , Mar Mediterrâneo , Nitrogênio/análise , Fósforo/análise , Polissacarídeos/análise , Dinâmica Populacional , Zooplâncton/química
9.
Sci Total Environ ; 353(1-3): 204-17, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16213005

RESUMO

The spatial and temporal variations of pico-, nano- and microphytoplankton abundance and composition were investigated over a 37 month period, focusing on the ecological role of different size classes of phytoplankton, and on the changes of the community structure that might occur during periods when large mucilage macroaggregates appear. Samples were collected monthly from June 1999 to July 2002 at 11 stations, along three transects covering the northern Adriatic basin. Highest abundances were observed in late-winter/spring for microphytoplankton (mainly diatoms), in spring-summer for nanophytoplankton, and in summer for picophytoplankton. The autotrophic component was more abundant in the summers of 2000 and 2002 (when large mucilage aggregates occurred) than in the summers of 1999 and 2001 (when a massive phenomenon was not observed). This increase was statistically significant for pico-, nano- and, among microphytoplankton, only for dinoflagellates. Blooms of picophytoplankton were often observed at the bottom layer during mucilage summers. The microphytoplankton community during mucilage phenomena was characterized by a species composition (Chaetoceros spp., Cerataulina pelagica, Pseudo-nitzschia delicatissima, P. pseudodelicatissima, Cylindrotheca closterium, Dactyliosolen fragilissimus) comparable to that observed in summers without extensive mucilage occurrence. However, some species appeared with significantly higher densities in the summers of 2000 and 2002: Ceratium furca, C. closterium, Oxytoxum spp., Hemiaulus hauckii and Gonyaulax fragilis. Microscopic observation of aggregates revealed that the microphytoplankton species composition inside the aggregates was comparable to that observed in the water column, with an enrichment of opportunistic species such as C. closterium and P. delicatissima. The presence of mucilage aggregates affects the phytoplankton populations in the water column, even when aggregates are at early stages. It seems that there is a mutual relationship between phytoplankton and aggregates, i.e., several diatom and dinoflagellate species may contribute to the aggregate formation and enlargement, but mucilage aggregates themselves may also affect the phytoplankton populations, allowing the development of a rich diatom community and in general enhancing nanophytoplankton growth.


Assuntos
Demografia , Ecossistema , Eucariotos/citologia , Biologia Marinha/estatística & dados numéricos , Fitoplâncton/citologia , Eucariotos/crescimento & desenvolvimento , Indóis , Mar Mediterrâneo , Fitoplâncton/crescimento & desenvolvimento , Dinâmica Populacional , Estações do Ano , Fatores de Tempo
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