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Dr. Luiz Mafra Jr.
Universidade Federal do Paraná

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0 Aquaculture
0 Ecotoxicology
0 Toxins
0 harmful algal bloom
0 Seafood safety

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Journal article
Published: 11 August 2021 in Toxins
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Ciguatera poisoning is a food intoxication associated with the consumption of fish or shellfish contaminated, through trophic transfer, with ciguatoxins (CTXs). In this study, we developed an experimental model to assess the trophic transfer of CTXs from herbivorous parrotfish, Chlorurus microrhinos, to carnivorous lionfish, Pterois volitans. During a 6-week period, juvenile lionfish were fed naturally contaminated parrotfish fillets at a daily dose of 0.11 or 0.035 ng CTX3C equiv. g−1, as measured by the radioligand-receptor binding assay (r-RBA) or neuroblastoma cell-based assay (CBA-N2a), respectively. During an additional 6-week depuration period, the remaining fish were fed a CTX-free diet. Using r-RBA, no CTXs were detectable in muscular tissues, whereas CTXs were measured in the livers of two out of nine fish sampled during exposure, and in four out of eight fish sampled during depuration. Timepoint pooled liver samples, as analyzed by CBA-N2a, confirmed the accumulation of CTXs in liver tissues, reaching 0.89 ng CTX3C equiv. g−1 after 41 days of exposure, followed by slow toxin elimination, with 0.37 ng CTX3C equiv. g−1 measured after the 6-week depuration. These preliminary results, which need to be pursued in adult lionfish, strengthen our knowledge on CTX transfer and kinetics along the food web.

ACS Style

Isabel Do Prado Leite; Khalil Sdiri; Angus Taylor; Jérôme Viallon; Hela Ben Gharbia; Luiz Laureno Mafra Júnior; Peter Swarzenski; François Oberhaensli; Hélène Taiana Darius; Mireille Chinain; Marie-Yasmine Dechraoui Bottein. Experimental Evidence of Ciguatoxin Accumulation and Depuration in Carnivorous Lionfish. Toxins 2021, 13, 564 .

AMA Style

Isabel Do Prado Leite, Khalil Sdiri, Angus Taylor, Jérôme Viallon, Hela Ben Gharbia, Luiz Laureno Mafra Júnior, Peter Swarzenski, François Oberhaensli, Hélène Taiana Darius, Mireille Chinain, Marie-Yasmine Dechraoui Bottein. Experimental Evidence of Ciguatoxin Accumulation and Depuration in Carnivorous Lionfish. Toxins. 2021; 13 (8):564.

Chicago/Turabian Style

Isabel Do Prado Leite; Khalil Sdiri; Angus Taylor; Jérôme Viallon; Hela Ben Gharbia; Luiz Laureno Mafra Júnior; Peter Swarzenski; François Oberhaensli; Hélène Taiana Darius; Mireille Chinain; Marie-Yasmine Dechraoui Bottein. 2021. "Experimental Evidence of Ciguatoxin Accumulation and Depuration in Carnivorous Lionfish." Toxins 13, no. 8: 564.

Journal article
Published: 16 November 2020 in Science of The Total Environment
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The marine dinoflagellate Vulcanodinium rugosum produces powerful paralyzing and cytotoxic compounds named pinnatoxins (PnTX) and portimines. Even though, no related human intoxication episodes following direct exposure in seawater or the ingestion of contaminated seafood have been documented so far. This study aimed at investigating a dinoflagellate bloom linked to acute dermatitis cases in two recreational beaches in Cienfuegos Bay, Cuba. We used epidemiological and clinical data from 60 dermatitis cases consisting of individuals in close contact with the bloom. Seawater physical-chemical properties were described, and the microorganism causing the bloom was identified by means of light and scanning electron microscopy. Morphological identification was confirmed genetically by sequencing the internal transcribed spacers ITS1 and ITS2, and the 5.8S rDNA region. Toxic compounds were identified from a bloom extract using liquid chromatography (LC) coupled to high-resolution mass spectrometry (HRMS), and their concentrations were estimated based on low-resolution tandem mass spectrometry (LC-MS/MS). Sixty people who had prolonged contact with the dinoflagellate bloom suffered acute dermal irritation. Most patients (79.2%) were children and had to be treated with antibiotics; some required >5-day hospitalization. Combined morphological and genetic characters indicated V. rugosum as the causative agent of the bloom. rDNA sequences of the V. rugosum genotype found in the bloom aligned with others from Asia, including material found in the ballast tank of a ship in Florida. The predominant toxins in the bloom were portimine, PnTX-F and PnTX-E, similar to strains originating from the Pacific Ocean. This bloom was associated with unusual weather conditions such as frequent and prolonged droughts. Our findings indicate a close link between the V. rugosum bloom and a dermatitis outbreak among swimmers in Cienfuegos Bay. Phylogenetic evidence suggests a recent introduction of V. rugosum from the Pacific Ocean into Caribbean waters, possibly via ballast water.

ACS Style

Angel R. Moreira-González; Augusto Comas-González; Aimee Valle-Pombrol; Mabel Seisdedo-Losa; Olidia Hernández-Leyva; Luciano F. Fernandes; Nicolas Chomérat; Gwenaël Bilien; Fabienne Hervé; Georges Augustin Rovillon; Philipp Hess; Carlos M. Alonso-Hernández; Luiz L. Mafra. Summer bloom of Vulcanodinium rugosum in Cienfuegos Bay (Cuba) associated to dermatitis in swimmers. Science of The Total Environment 2020, 757, 143782 .

AMA Style

Angel R. Moreira-González, Augusto Comas-González, Aimee Valle-Pombrol, Mabel Seisdedo-Losa, Olidia Hernández-Leyva, Luciano F. Fernandes, Nicolas Chomérat, Gwenaël Bilien, Fabienne Hervé, Georges Augustin Rovillon, Philipp Hess, Carlos M. Alonso-Hernández, Luiz L. Mafra. Summer bloom of Vulcanodinium rugosum in Cienfuegos Bay (Cuba) associated to dermatitis in swimmers. Science of The Total Environment. 2020; 757 ():143782.

Chicago/Turabian Style

Angel R. Moreira-González; Augusto Comas-González; Aimee Valle-Pombrol; Mabel Seisdedo-Losa; Olidia Hernández-Leyva; Luciano F. Fernandes; Nicolas Chomérat; Gwenaël Bilien; Fabienne Hervé; Georges Augustin Rovillon; Philipp Hess; Carlos M. Alonso-Hernández; Luiz L. Mafra. 2020. "Summer bloom of Vulcanodinium rugosum in Cienfuegos Bay (Cuba) associated to dermatitis in swimmers." Science of The Total Environment 757, no. : 143782.

Journal article
Published: 15 May 2020 in Toxins
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Coolia is a genus of marine benthic dinoflagellates which is widely distributed in tropical and temperate zones. Toxicity has been reported in selected Coolia species, although the identity of causative compounds is still controversial. In this study, we investigated the taxonomical and toxicological aspects of Coolia species from Brazil. Since light- and electron microscopy-based morphology was not enough to distinguish small-celled species, ITS and LSU D1-D3 phylogenetic analyses were used for species definition. Cultures of Coolia palmyrensis and Coolia santacroce were established from samples collected along the northeastern Brazilian coast, the first record of both species in South Atlantic waters. Cultures of Coolia malayensis and Coolia tropicalis were also established and exhibited acute in vivo toxicity to adults of Artemia salina, while C. palmyrensis and C. santacroce were non-toxic. The presence of 30 yessotoxin analogues, 7 metabolites of Coolia and 44 Gambierdiscus metabolites was screened in 14 strains of Coolia. 44-methyl gambierone (formerly referred to as MTX3) and a new isomer of this compound were detected only in C. tropicalis, using both low- and high-resolution LC-MS/MS. To our knowledge, this is the first report of gambierone analogues in dinoflagellates other than Gambierdiscus; the role of C. tropicalis in ciguatera poisoning thus deserves to be considered in further investigations.

ACS Style

Carlos Eduardo Junqueira De Azevedo Tibiriçá; Manoella Sibat; Luciano Felício Fernandes; Gwenaël Bilien; Nicolas Chomérat; Philipp Hess; Luiz L. Mafra Jr; Luiz L. Mafra. Diversity and Toxicity of the Genus Coolia Meunier in Brazil, and Detection of 44-methyl Gambierone in Coolia tropicalis. Toxins 2020, 12, 327 .

AMA Style

Carlos Eduardo Junqueira De Azevedo Tibiriçá, Manoella Sibat, Luciano Felício Fernandes, Gwenaël Bilien, Nicolas Chomérat, Philipp Hess, Luiz L. Mafra Jr, Luiz L. Mafra. Diversity and Toxicity of the Genus Coolia Meunier in Brazil, and Detection of 44-methyl Gambierone in Coolia tropicalis. Toxins. 2020; 12 (5):327.

Chicago/Turabian Style

Carlos Eduardo Junqueira De Azevedo Tibiriçá; Manoella Sibat; Luciano Felício Fernandes; Gwenaël Bilien; Nicolas Chomérat; Philipp Hess; Luiz L. Mafra Jr; Luiz L. Mafra. 2020. "Diversity and Toxicity of the Genus Coolia Meunier in Brazil, and Detection of 44-methyl Gambierone in Coolia tropicalis." Toxins 12, no. 5: 327.

Journal article
Published: 22 January 2020 in Toxins
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Recurrent blooms of Ostreopsis cf. ovata have been reported in Brazil and the Mediterranean Sea with associated ecological, and in the latter case, health impacts. Molecular data based on the D1–D3 and D8–D10 regions of the LSU rDNA and ITS loci, and the morphology of O. cf. ovata isolates and field populations from locations along the Brazilian tropical and subtropical coastal regions and three oceanic islands are presented. Additional ITS sequences from three single cells from the tropical coast are provided. Toxin profiles and quantities of PLTX and their analogues; OVTXs; contained in cells from two clonal cultures and two field blooms from Rio de Janeiro were investigated. Morphology was examined using both light and epifluorescence microscopy. Morphometric analysis of different strains and field populations from diverse locations were compared. Molecular analysis showed that six of the seven sequences grouped at the large “Atlantic/Mediterranean/Pacific” sub-clade, while one sequence branched in a sister clade with sequences from Madeira Island and Greece. The toxin profile of strains and bloom field samples from Rio de Janeiro were dominated by OVTX-a and -b, with total cell quotas (31.3 and 39.3 pg cell−1) in the range of that previously reported for strains of O. cf. ovata.

ACS Style

Silvia Nascimento; Raquel Neves; Gabriela De’Carli; Geovanna Borsato; Rodrigo da Silva; Guilherme Melo; Agatha de Morais; Thais Cockell; Santiago Fraga; Adriana Menezes-Salgueiro; Luiz Mafra; Philipp Hess; Fabiano Salgueiro. Ostreopsis cf. ovata (Dinophyceae) Molecular Phylogeny, Morphology, and Detection of Ovatoxins in Strains and Field Samples from Brazil. Toxins 2020, 12, 70 .

AMA Style

Silvia Nascimento, Raquel Neves, Gabriela De’Carli, Geovanna Borsato, Rodrigo da Silva, Guilherme Melo, Agatha de Morais, Thais Cockell, Santiago Fraga, Adriana Menezes-Salgueiro, Luiz Mafra, Philipp Hess, Fabiano Salgueiro. Ostreopsis cf. ovata (Dinophyceae) Molecular Phylogeny, Morphology, and Detection of Ovatoxins in Strains and Field Samples from Brazil. Toxins. 2020; 12 (2):70.

Chicago/Turabian Style

Silvia Nascimento; Raquel Neves; Gabriela De’Carli; Geovanna Borsato; Rodrigo da Silva; Guilherme Melo; Agatha de Morais; Thais Cockell; Santiago Fraga; Adriana Menezes-Salgueiro; Luiz Mafra; Philipp Hess; Fabiano Salgueiro. 2020. "Ostreopsis cf. ovata (Dinophyceae) Molecular Phylogeny, Morphology, and Detection of Ovatoxins in Strains and Field Samples from Brazil." Toxins 12, no. 2: 70.

Original article
Published: 01 January 2020 in Ocean and Coastal Research
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This study addressed the occurrence and distribution of benthic microalgae, with emphasis on toxic species, on different substrates (macroalgae, seagrass and sediments) along the outer, euhaline zone of the Estuarine Complex of Paranaguá Bay, southern Brazil, from July 2015 to May 2016. Canonical analysis of principal coordinates (CAP) was used to identify the potential environmental drivers of microphytobenthic assemblage structure. A total of 18 potentially toxic benthic microalgae species were reported, including 7 dinoflagellates, 9 cyanobacteria, one diatom and one euglenophyte. The abundance of all potentially toxic microalgae varied consistently along the investigated period. Dinoflagellates dominated the microalgae assemblage in July and September 2015. Mean densities on macrophytes ranged from 33.6 cells g-1 in May 2016 to 775.6 cells g-1 in September 2015, being positively correlated with dissolved nitrogen-nutrients, water transparency, salinity, and chlorophyll-a. Prorocentrum cf. lima was the most frequent and abundant dinoflagellate. Overall, the highest abundance of toxic species occurred in February 2016, when cyanobacterial mats dominated by Lyngbya cf. aestuarii were observed throughout the estuary associated with periods of heavier rainfall and higher turbidity (shallower Secchi depth). At that time, a selected microphytobenthic extract exhibited acute toxicity on nauplii of the brine shrimp Artemia salina in the laboratory.

ACS Style

Angel Ramón Moreira-González; Marco Colossi Brustolin; Luiz Laureno Mafra Junior. Composition and abundance of benthic microalgae from the Estuarine Complex of Paranaguá Bay (southern Brazil) with special emphasis on toxic species. Ocean and Coastal Research 2020, 68, 1 .

AMA Style

Angel Ramón Moreira-González, Marco Colossi Brustolin, Luiz Laureno Mafra Junior. Composition and abundance of benthic microalgae from the Estuarine Complex of Paranaguá Bay (southern Brazil) with special emphasis on toxic species. Ocean and Coastal Research. 2020; 68 ():1.

Chicago/Turabian Style

Angel Ramón Moreira-González; Marco Colossi Brustolin; Luiz Laureno Mafra Junior. 2020. "Composition and abundance of benthic microalgae from the Estuarine Complex of Paranaguá Bay (southern Brazil) with special emphasis on toxic species." Ocean and Coastal Research 68, no. : 1.

Journal article
Published: 01 November 2019 in Harmful Algae
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On June 2016, a major bloom of Dinophysis acuminata complex was noticed over the coast of Paraná State (PR), southern Brazil, an area unprotected by any official monitoring program. Here we report the results of an extensive sampling effort that ultimately led PR authorities to issue the first State shellfish-harvesting ban due to multi-species okadaic acid (OA) contamination. During its peak, the bloom covered an area of 201 km2 (∼2.0-3.5 × 54.0 km), attaining unprecedentedly high cell densities along the shallow (<15 m) continental shelf (mean 2.2 × 105, maximum 2.1 × 106 cells L-1) and adjacent sandy beaches (mean 2.8 × 105, maximum 5.2 × 106 cells L-1). Only OA was detected in suspension (max. 188 ng L-1). Toxin levels measured in bivalves were several times greater than the regulatory limit of 160 ng g-1, reaching up to 3600 ng g-1 in Crassostrea gasar, by far the highest OA concentrations ever reported in oysters worldwide, 7700 ng g-1 in brown mussels, Perna perna, and lower levels in clams, Anomalocardia brasiliana, and mangrove mussels, Mytella spp. Nine cases of human intoxication were officially reported and five people were hospitalized with typical symptoms of Diarrhetic Shellfish Poisoning linked to the consumption of contaminated bivalves. All bivalves quickly converted most of the OA into its esterified form, DTX-3, and eliminated the toxins only a few weeks following the bloom, with C. gasar being the slowest-detoxifying species. Lower OA levels were accumulated in zooplankton, gastropods and several novel toxin vectors, including benthic organisms such as sand dollars Mellita quinquiesperforata and the ghost-shrimp Callichirus major, which may act as a good indicator of the presence of toxins in sandy beaches, and pelagic fish species that can serve as potential alternative sources of OA to humans (Chaetodipterus faber and Mugil liza). Monitoring toxin contamination in seafood other than bivalves is thus recommended to ensure comprehensive human health protection during massive Dinophysis blooms. Additionally, since OA was also present at low concentrations in the liver of Guiana dolphins Sotalia guianensis and penguins Spheniscus magellanicus, exposure to biotoxins should be considered in conservation actions involving threatened and near-threatened marine organisms in this region.

ACS Style

L.L. Mafra; P.K.W. Nolli; L.E. Mota; Camila Domit; M. Soeth; L.F.G. Luz; B.F. Sobrinho; J.G. Leal; M. Di Domenico. Multi-species okadaic acid contamination and human poisoning during a massive bloom of Dinophysis acuminata complex in southern Brazil. Harmful Algae 2019, 89, 101662 .

AMA Style

L.L. Mafra, P.K.W. Nolli, L.E. Mota, Camila Domit, M. Soeth, L.F.G. Luz, B.F. Sobrinho, J.G. Leal, M. Di Domenico. Multi-species okadaic acid contamination and human poisoning during a massive bloom of Dinophysis acuminata complex in southern Brazil. Harmful Algae. 2019; 89 ():101662.

Chicago/Turabian Style

L.L. Mafra; P.K.W. Nolli; L.E. Mota; Camila Domit; M. Soeth; L.F.G. Luz; B.F. Sobrinho; J.G. Leal; M. Di Domenico. 2019. "Multi-species okadaic acid contamination and human poisoning during a massive bloom of Dinophysis acuminata complex in southern Brazil." Harmful Algae 89, no. : 101662.

Journal article
Published: 27 July 2019 in Toxins
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Ostreopsis cf. ovata is a toxic marine benthic dinoflagellate responsible for harmful blooms affecting ecosystem and human health, mostly in the Mediterranean Sea. In this study we report the occurrence of a summer O. cf. ovata bloom in Currais, a coastal archipelago located on the subtropical Brazilian coast (~25° S). This bloom was very similar to Mediterranean episodes in many aspects: (a) field-sampled and cultivated O. cf. ovata cells aligned phylogenetically (ITS and LSU regions) along with Mediterranean strains; (b) the bloom occurred at increasing temperature and irradiance, and decreasing wind speed; (c) cell densities reached up to 8.0 × 104 cell cm−2 on fiberglass screen and 5.6 × 105 cell g−1 fresh weight on seaweeds; (d) and toxin profiles were composed mostly of ovatoxin-a (58%) and ovatoxin-b (32%), up to 35.5 pg PLTX-eq. cell−1 in total. Mussels were contaminated during the bloom with unsafe toxin levels (up to 131 µg PLTX-eq. kg−1). Ostreopsis cells attached to different plastic litter, indicating an alternate route for toxin transfer to marine fauna via ingestion of biofilm-coated plastic debris.

ACS Style

Carlos Eduardo J. A. Tibiriçá; Isabel P. Leite; Talita V. V. Batista; Luciano F. Fernandes; Nicolas Chomérat; Fabienne Herve; Philipp Hess; Jr. Luiz L. Mafra. Ostreopsis cf. ovata Bloom in Currais, Brazil: Phylogeny, Toxin Profile and Contamination of Mussels and Marine Plastic Litter. Toxins 2019, 11, 446 .

AMA Style

Carlos Eduardo J. A. Tibiriçá, Isabel P. Leite, Talita V. V. Batista, Luciano F. Fernandes, Nicolas Chomérat, Fabienne Herve, Philipp Hess, Jr. Luiz L. Mafra. Ostreopsis cf. ovata Bloom in Currais, Brazil: Phylogeny, Toxin Profile and Contamination of Mussels and Marine Plastic Litter. Toxins. 2019; 11 (8):446.

Chicago/Turabian Style

Carlos Eduardo J. A. Tibiriçá; Isabel P. Leite; Talita V. V. Batista; Luciano F. Fernandes; Nicolas Chomérat; Fabienne Herve; Philipp Hess; Jr. Luiz L. Mafra. 2019. "Ostreopsis cf. ovata Bloom in Currais, Brazil: Phylogeny, Toxin Profile and Contamination of Mussels and Marine Plastic Litter." Toxins 11, no. 8: 446.

Article
Published: 16 July 2019 in Journal of Applied Phycology
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The present study investigated selected benthic dinoflagellates isolated from different regions from the Western Atlantic, with respect to their morphology, growth, toxicity, and toxin production in culture. A total of nine strains of benthic dinoflagellates belonging to three genera were cultivated: Amphidinium massartii, Amphidinium operculatum (2 strains), Coolia malayensis (2 strains), Prorocentrum hoffmannianum (2 strains), and Prorocentrum mexicanum, whose morphological and genetic characterizations matched previous descriptions, and Prorocentrum sp., morphologically related to P. cf. norrissianum. The two strains of C. malayensis from Brazil attained the highest growth rates (0.42–0.47 day−1), but the lowest cell densities (2.2–2.9 × 104 cells mL−1) in culture. The highest cell densities were recorded for A. massartii from Cuba (3.8 × 105 cells mL−1). All species/strains investigated exhibited moderate toxicity to larvae of the brine shrimp Artemia salina; A. massartii being the most toxic species and Prorocentrum sp. the least one. Additionally, extracts of Prorocentrum species (P. hoffmannianum and Prorocentrum sp.) tested positive in mouse bioassays following intraperitoneal injection. Moderate to high concentrations of okadaic acid (OA), but no dinophysistoxins (DTXs), were found in both P. hoffmannianum strains from Cuba; but no diarrheic toxins were detected in either P. mexicanum from Cuba or Prorocentrum sp. from southern Brazil. Finally, five novel amphidinols were detected in cultures of both A. massartii (Cuba) and A. operculatum (Brazil) by LC-MS/MS, with molecular weights of 1440.8 (two isomers), 1360.8, 1287.7, and 984.6. These findings clearly indicate the need to include benthic species among the harmful microalgae surveyed in regional monitoring programs of phytoplankton.

ACS Style

Angel R. Moreira-González; Luciano F. Fernandes; Hajime Uchida; Aya Uesugi; Toshiyuki Suzuki; Nicolas Chomérat; Gwenaël Bilien; Thiago Alves Pereira; Luiz L. Mafra. Morphology, growth, toxin production, and toxicity of cultured marine benthic dinoflagellates from Brazil and Cuba. Journal of Applied Phycology 2019, 31, 3699 -3719.

AMA Style

Angel R. Moreira-González, Luciano F. Fernandes, Hajime Uchida, Aya Uesugi, Toshiyuki Suzuki, Nicolas Chomérat, Gwenaël Bilien, Thiago Alves Pereira, Luiz L. Mafra. Morphology, growth, toxin production, and toxicity of cultured marine benthic dinoflagellates from Brazil and Cuba. Journal of Applied Phycology. 2019; 31 (6):3699-3719.

Chicago/Turabian Style

Angel R. Moreira-González; Luciano F. Fernandes; Hajime Uchida; Aya Uesugi; Toshiyuki Suzuki; Nicolas Chomérat; Gwenaël Bilien; Thiago Alves Pereira; Luiz L. Mafra. 2019. "Morphology, growth, toxin production, and toxicity of cultured marine benthic dinoflagellates from Brazil and Cuba." Journal of Applied Phycology 31, no. 6: 3699-3719.

Article
Published: 02 August 2018 in Environmental Biology of Fishes
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Benthic dinoflagellates belonging to the genus Prorocentrum are known to produce diarrhetic toxins such as okadaic acid (OA) and its analogues, dinophysistoxins (DTXs), as well as prorocentrolides and other unidentified fast-acting toxins. The present study is a comparative analysis focused on the morphology, genetic, growth, toxin production, and toxicity by strains belonging to the Prorocentrum lima species complex, isolated from different regions along the western Atlantic coast. While cell dimensions (38–45 × 24–30 μm) and shape (ovoid) were similar between strains from Cuba and Recife (Northeast Brazil), cells of the strain from the estuarine complex of Paranaguá Bay (South Brazil) were shorter (36–41 × 25–28 μm) and oblong to ovate-oblong (elliptical) in shape. This latter strain exhibited similar LSU rDNA and identical ITS1-5.8S rDNA-ITS2 sequences to those of P. cf. lima “morphotype 5,” which is closely related to Prorocentrum caipirignum by LSU, but separated from it by ITS. This southern Brazilian strain attained the highest growth rate (0.34 ± 0.01 div day−1) and cell densities (11.2 × 105 cell mL−1) in batch culture. Intracellular OA concentrations were higher for the other two strains during the late exponential and stationary phase, but similar for all strains (9.50–10.06 pg cell−1) at the early exponential growth phase; consistently lower levels of DTX-1 were produced by two strains, except the one from Recife. Finally, live cells of the strains from Cuba and Recife were more toxic to A. salina metanauplii, whereas the southern Brazilian strain exhibited higher culture medium toxicity. The contrasts in growth and toxicity potential revealed for these morphologically and genetically distinct Prorocentrum strains might be relevant for the local management of diarrhetic poisoning outbreaks in shellfish harvesting and aquaculture sites, including in estuarine areas.

ACS Style

Angel R. Moreira-González; Luciano F. Fernandes; Hajime Uchida; Aya Uesugi; Toshiyuki Suzuki; Nicolas Chomérat; Gwenaël Bilien; Luiz L. Mafra. Variations in morphology, growth, and toxicity among strains of the Prorocentrum lima species complex isolated from Cuba and Brazil. Environmental Biology of Fishes 2018, 31, 519 -532.

AMA Style

Angel R. Moreira-González, Luciano F. Fernandes, Hajime Uchida, Aya Uesugi, Toshiyuki Suzuki, Nicolas Chomérat, Gwenaël Bilien, Luiz L. Mafra. Variations in morphology, growth, and toxicity among strains of the Prorocentrum lima species complex isolated from Cuba and Brazil. Environmental Biology of Fishes. 2018; 31 (1):519-532.

Chicago/Turabian Style

Angel R. Moreira-González; Luciano F. Fernandes; Hajime Uchida; Aya Uesugi; Toshiyuki Suzuki; Nicolas Chomérat; Gwenaël Bilien; Luiz L. Mafra. 2018. "Variations in morphology, growth, and toxicity among strains of the Prorocentrum lima species complex isolated from Cuba and Brazil." Environmental Biology of Fishes 31, no. 1: 519-532.

Article
Published: 09 November 2017 in Environmental Monitoring and Assessment
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Pseudo-nitzschia is a diatom genus capable of producing the neurotoxin domoic acid (DA), which has been related to mortalities of marine vertebrates, and the amnesic shellfish poisoning (ASP) in human consumers of contaminated bivalves. This study reports DA production among Pseudo-nitzschia strains isolated from shellfish farming areas in southern Brazil. Twenty-seven cultures of potentially toxigenic Pseudo-nitzschia species were established. Growth, stepped-chain formation, and DA production were evaluated in static, intermittently illuminated (12:12 photoperiod) batch cultures for 12 selected strains, and under continuous light and/or turbulence for a single Pseudo-nitzschia calliantha strain. Growth rate ranged from 0.16 to 0.39 day−1 among the 12 strains. Only P. calliantha and P. cf. multiseries yielded detectable levels of intracellular DA, reaching up to 0.054 fg cell−1 in late exponential and 0.15 pg cell−1 in early stationary phase, respectively. Continuous light impaired cell growth, and turbulence enhanced step-chain formation by threefold during exponential growth phase, but no DA production was detected under both conditions. The effect of turbulence on chain formation should be further evaluated in the field, once particle size is expected to affect the ingestion of toxic cells and thus toxin accumulation by certain DA vectors. The low cell toxicity revealed herein under laboratory conditions is in accordance with the low frequency of DA contamination episodes in south Brazilian waters. Nevertheless, monitoring of Pseudo-nitzschia abundance and DA presence in farming areas is continuously required to assure the quality of local shellfish products.

ACS Style

Pedro Rebelo Wadt; Luiz Laureno Mafra; Camila Prestes Dos Santos Tavares; Luciano Felício Fernandes; Luís Antonio De Oliveira Proença. Growth, chain formation, and toxin production by southern Brazilian Pseudo-nitzschia isolates under laboratory conditions. Environmental Monitoring and Assessment 2017, 189, 621 .

AMA Style

Pedro Rebelo Wadt, Luiz Laureno Mafra, Camila Prestes Dos Santos Tavares, Luciano Felício Fernandes, Luís Antonio De Oliveira Proença. Growth, chain formation, and toxin production by southern Brazilian Pseudo-nitzschia isolates under laboratory conditions. Environmental Monitoring and Assessment. 2017; 189 (12):621.

Chicago/Turabian Style

Pedro Rebelo Wadt; Luiz Laureno Mafra; Camila Prestes Dos Santos Tavares; Luciano Felício Fernandes; Luís Antonio De Oliveira Proença. 2017. "Growth, chain formation, and toxin production by southern Brazilian Pseudo-nitzschia isolates under laboratory conditions." Environmental Monitoring and Assessment 189, no. 12: 621.

Journal article
Published: 24 October 2017 in Marine Drugs
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In order to assess the effects of Fe-enrichment on the growth and domoic acid (DA) production of the toxigenic diatom Pseudo-nitzschia multiseries, static cultures that received the addition of different iron (Fe) concentrations were maintained for 30 days. Intra- and extracellular DA concentrations were evaluated over time, and growth and chain-formation were compared to those of non-toxic diatoms, Bacillaria sp. Growth rates of P. multiseries (μ = 0.45–0.73 d−1) were similar among cultures containing different Fe concentrations. Likewise, the similar incidence and length of P. multiseries stepped cell chains (usually 2–4; up to 8-cell long) among the treatments reinforces that the cultures were not growth-inhibited under any condition tested, suggesting an efficient Fe acquisition mechanism. Moreover, DA concentrations were significantly higher under the highest Fe concentration, indicating that Fe is required for toxin synthesis. Bacillaria sp. reached comparable growth rates under the same Fe concentrations, except when the dissolved cell contents from a P. multiseries culture was added. The 50–70% reduction in cell density and 70–90% decrease in total chlorophyll-a content of Bacillaria sp. at early stationary growth phase indicates, for the first time, an allelopathic effect of undetermined compounds released by Pseudo-nitzschia to another diatom species.

ACS Style

Bruna Fernanda Sobrinho; Luana Mocelin De Camargo; Leonardo Sandrini-Neto; Cristian Rafael Kleemann; Eunice Da Costa Machado; Luiz Laureno Mafra. Growth, Toxin Production and Allelopathic Effects of Pseudo-nitzschia multiseries under Iron-Enriched Conditions. Marine Drugs 2017, 15, 331 .

AMA Style

Bruna Fernanda Sobrinho, Luana Mocelin De Camargo, Leonardo Sandrini-Neto, Cristian Rafael Kleemann, Eunice Da Costa Machado, Luiz Laureno Mafra. Growth, Toxin Production and Allelopathic Effects of Pseudo-nitzschia multiseries under Iron-Enriched Conditions. Marine Drugs. 2017; 15 (10):331.

Chicago/Turabian Style

Bruna Fernanda Sobrinho; Luana Mocelin De Camargo; Leonardo Sandrini-Neto; Cristian Rafael Kleemann; Eunice Da Costa Machado; Luiz Laureno Mafra. 2017. "Growth, Toxin Production and Allelopathic Effects of Pseudo-nitzschia multiseries under Iron-Enriched Conditions." Marine Drugs 15, no. 10: 331.

Journal article
Published: 07 October 2016 in Harmful Algae
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Toxigenic Dinophysis spp. are obligate mixotrophic dinoflagellates that require a constant supply of prey—Mesodinium rubrum—to achieve long-term growth by means of kleptoplasty. Mesodinium rubrum is, however, a fast moving, jumping ciliate exhibiting an effective escape response from suspensivorous predators. In the present study, a series of laboratory experiments evaluating the motility and survival of M. rubrum in the presence of Dinophysis cells and/or substances contained in their culture medium was designed, in order to assess the mechanisms involved in prey capture by Dinophysis spp. Cell abundance of M. rubrum decreased in the presence of Dinophysis cf. ovum cells producing okadaic acid (OA; up to 7.94 ± 2.67 pg cell−1) and smaller amounts of dinophysistoxin-1 (DTX-1) and pectenotoxin-2 (PTX-2). Prey capture was often observed after the ciliate had been attached to adhesive “mucus traps”, which only appeared in the presence of Dinophysis cells. Before being attached to the mucus traps, M. rubrum cells reduced significantly their swimming frequency (from ∼41 to 19 ± 3 jumps min−1) after only 4 h of initial contact with D. cf. ovum cells. M. rubrum survival was not affected in contact with purified OA, DTX-1 and PTX-2 solutions, but decreased significantly when the ciliate was exposed to cell-free or filtered culture medium from both D. cf. ovum and D. caudata, the latter containing moderate concentrations of free eicosapentaenoic acid and docosahexaenoic acid. The results thus indicate that Dinophysis combines the release of toxic compounds other than shellfish toxins, possibly free PUFAs, and a “mucus trap” to enhance its prey capture success by immobilizing and subsequently arresting M. rubrum cells.

ACS Style

Luiz L. Mafra Jr.; Satoshi Nagai; Hajime Uchida; Camila P.S. Tavares; Bruno P. Escobar; Toshiyuki Suzuki. Harmful effects of Dinophysis to the ciliate Mesodinium rubrum: Implications for prey capture. Harmful Algae 2016, 59, 82 -90.

AMA Style

Luiz L. Mafra Jr., Satoshi Nagai, Hajime Uchida, Camila P.S. Tavares, Bruno P. Escobar, Toshiyuki Suzuki. Harmful effects of Dinophysis to the ciliate Mesodinium rubrum: Implications for prey capture. Harmful Algae. 2016; 59 ():82-90.

Chicago/Turabian Style

Luiz L. Mafra Jr.; Satoshi Nagai; Hajime Uchida; Camila P.S. Tavares; Bruno P. Escobar; Toshiyuki Suzuki. 2016. "Harmful effects of Dinophysis to the ciliate Mesodinium rubrum: Implications for prey capture." Harmful Algae 59, no. : 82-90.

Journal article
Published: 18 June 2015 in Marine Drugs
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This study investigates the occurrence of diarrhetic shellfish toxins (DSTs) and their producing phytoplankton species in southern Brazil, as well as the potential for toxin accumulation in co-occurring mussels (Perna perna) and octopuses (Octopus vulgaris). During the spring in 2012 and 2013, cells of Dinophysis acuminata complex were always present, sometimes at relatively high abundances (max. 1143 cells L−1), likely the main source of okadaic acid (OA) in the plankton (max. 34 ng L−1). Dinophysis caudata occurred at lower cell densities in 2013 when the lipophilic toxins pectenotoxin-2 (PTX-2) and PTX-2 seco acid were detected in plankton and mussel samples. Here, we report for the first time the accumulation of DSTs in octopuses, probably linked to the consumption of contaminated bivalves. Perna perna mussels were consistently contaminated with different DSTs (max. 42 µg kg−1), and all octopuses analyzed (n = 5) accumulated OA in different organs/tissues: digestive glands (DGs) > arms > gills > kidneys > stomach + intestine. Additionally, similar concentrations of 7-O-palmytoyl OA and 7-O-palmytoly dinophysistoxin-1 (DTX-1) were frequently detected in the hepatopancreas of P. perna and DGs of O. vulgaris. Therefore, octopuses can be considered a potential vector of DSTs to both humans and top predators such as marine mammals.

ACS Style

Jr. Luiz L. Mafra; Daiana Lopes; Vanessa C. Bonilauri; Hajime Uchida; Toshiyuki Suzuki. Persistent Contamination of Octopuses and Mussels with Lipophilic Shellfish Toxins during Spring Dinophysis Blooms in a Subtropical Estuary. Marine Drugs 2015, 13, 3920 -3935.

AMA Style

Jr. Luiz L. Mafra, Daiana Lopes, Vanessa C. Bonilauri, Hajime Uchida, Toshiyuki Suzuki. Persistent Contamination of Octopuses and Mussels with Lipophilic Shellfish Toxins during Spring Dinophysis Blooms in a Subtropical Estuary. Marine Drugs. 2015; 13 (6):3920-3935.

Chicago/Turabian Style

Jr. Luiz L. Mafra; Daiana Lopes; Vanessa C. Bonilauri; Hajime Uchida; Toshiyuki Suzuki. 2015. "Persistent Contamination of Octopuses and Mussels with Lipophilic Shellfish Toxins during Spring Dinophysis Blooms in a Subtropical Estuary." Marine Drugs 13, no. 6: 3920-3935.

Original article
Published: 30 April 2015 in Fisheries Science
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A bloom of D. acuminata complex was detected in early March 2008 in the shellfish farming area of Baía Sul, southern Brazil. Cell density reached up to 4.7 × 104 cells/L at the surface by March 31st, quickly decreasing (32) in all sampling stations. On average, commercial-sized mussels, Perna perna, accumulated 11-fold higher okadaic acid (OA) levels in the digestive glands (DG) (maximum 2422 ng/g) compared to those of oysters, Crassostrea gigas (maximum 271 ng/g). Moreover, 50 % of the mussel DG extracts tested (n = 42) produced acute toxic effects as assessed by mouse bioassay, whereas all oyster samples produced negative results (n = 17). In parallel, juvenile oysters, Crassostrea brasiliana and C. gigas, and juvenile mussels, P. perna, exposed to a laboratory-simulated D. acuminata complex bloom (1350–13,750 cells/L) accumulated 7.5, 23.4, and 51.1 ng OA/g in whole bodies (22.7, 66.1, and 183.3 ng OA/g in visceral tissues), respectively. Toxin levels in the whole bodies dropped to similarly low average levels in all bivalve species (3.6, 3.7, and 1.3 ng/g, respectively) after 168 h of depuration. Mussels, therefore, detoxified OA at faster rates (0.023/h) than oysters C. gigas (0.010/h) and C. brasiliana (0.004/h).

ACS Style

Luiz Laureno Mafra; Tatiany Ribas; Thiago Pereira Alves; Luís Antonio Oliveira Proença; Mathias Alberto Schramm; Hajime Uchida; Toshiyuki Suzuki. Differential okadaic acid accumulation and detoxification by oysters and mussels during natural and simulated Dinophysis blooms. Fisheries Science 2015, 81, 749 -762.

AMA Style

Luiz Laureno Mafra, Tatiany Ribas, Thiago Pereira Alves, Luís Antonio Oliveira Proença, Mathias Alberto Schramm, Hajime Uchida, Toshiyuki Suzuki. Differential okadaic acid accumulation and detoxification by oysters and mussels during natural and simulated Dinophysis blooms. Fisheries Science. 2015; 81 (4):749-762.

Chicago/Turabian Style

Luiz Laureno Mafra; Tatiany Ribas; Thiago Pereira Alves; Luís Antonio Oliveira Proença; Mathias Alberto Schramm; Hajime Uchida; Toshiyuki Suzuki. 2015. "Differential okadaic acid accumulation and detoxification by oysters and mussels during natural and simulated Dinophysis blooms." Fisheries Science 81, no. 4: 749-762.

Journal article
Published: 01 August 2014 in Journal of Sea Research
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ACS Style

Marco C. Brustolin; Micheli C. Thomas; Luiz L. Mafra; Paulo Da Cunha Lana. Does Encope emarginata (Echinodermata: Echinoidea) affect spatial variation patterns of estuarine subtidal meiofauna and microphytobenthos? Journal of Sea Research 2014, 91, 70 -78.

AMA Style

Marco C. Brustolin, Micheli C. Thomas, Luiz L. Mafra, Paulo Da Cunha Lana. Does Encope emarginata (Echinodermata: Echinoidea) affect spatial variation patterns of estuarine subtidal meiofauna and microphytobenthos? Journal of Sea Research. 2014; 91 ():70-78.

Chicago/Turabian Style

Marco C. Brustolin; Micheli C. Thomas; Luiz L. Mafra; Paulo Da Cunha Lana. 2014. "Does Encope emarginata (Echinodermata: Echinoidea) affect spatial variation patterns of estuarine subtidal meiofauna and microphytobenthos?" Journal of Sea Research 91, no. : 70-78.