Luciana Retz Carvalho - Academia.edu (original) (raw)

Papers by Luciana Retz Carvalho

Research paper thumbnail of Avaliação de atividade fungitóxica e isolamento de aloaromadendrano - 4α, 10 β - diol em Hypericum cordatum

Revista Brasileira de Plantas Medicinais, 2014

Hypericum cordatum é uma espécie do cerrado que foi selecionada em triagem de plantas com ativida... more Hypericum cordatum é uma espécie do cerrado que foi selecionada em triagem de plantas com atividade fungitóxica. O objetivo do presente trabalho foi isolar e identificar compostos com atividade antifúngica em extratos de folhas em diclorometano. O pó das folhas das plantas foi submetido à extração exaustiva com éter de petróleo e diclorometano. O extrato em diclorometano, e as frações ativas, foram submetidos à fracionamentos biomonitorados em coluna de Sephadex LH-20, respectivamente, com os eluentes clorofórmio:metanol (1:1) e com um gradiente de hexano:diclorometano (1:4); diclorometano:acetona (3:2 e 1:4), metanol, e água. As frações que mostraram atividade foram submetidas à cromatografia em camada delgada preparativa de sílica gel GF254, sendo que o material de maior massa foi analisado em CLAE semipreparativa. A fração ativa foi analisada por RMN de ¹H, tendo sido identificado o aloaromadendrano - 4α -10β - diol como componente principal da fração. Conclui-se, portanto, que e...

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Research paper thumbnail of The influence of temperature on Radiocystis fernandoi strain (cyanobacteria) growth and microcystin production

Brazilian Journal of Botany, 2018

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Research paper thumbnail of Article Analysis of the Toxicity and Histopathology Induced by the Oral Administration of Pseudanabaena galeata and Geitlerinema splendidum (Cyanobacteria) Extracts to Mice

marine drugs

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Research paper thumbnail of Dichotomaria marginata (Rhodophyta) as a bioindicator for marine pollution: An overview about its metabolites and adsorbed pollutants

Revista de Biología Marina y Oceanografía, 2020

Macroalgae are considered bioindicators for marine pollution, because they have the ability to qu... more Macroalgae are considered bioindicators for marine pollution, because they have the ability to quickly react to changes in their environment. In consequence, macroalgae populations fluctuate, according to species characteristics and adaptive strategies. Their cell wall polysaccharides contain sulfate groups that are capable of retaining and accumulating heavy metals. In addition to traditional contaminants, emerging pollutants are being recognized in aquatic environments. Herein, emerging pollutants have been identified after being desorbed from the macroalga Dichotomaria marginata, collected from Fortaleza Beach, Ubatuba -SP, Brazil. Based on that algal polysaccharide networks have the potential of forming hydrogen bonds with polar compounds, it was hypothesized that these pollutants would be bound to sugar polymers. Compounds present in the D. marginata samples were identified using both gas and liquid chromatography/mass spectrometry (GC/MS and HPLC/MS), assisted by computational...

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Research paper thumbnail of Efeito inibitório de extratos de cianobactérias frente ao vírus Herpes simplex tipo 1

Xiv Congresso Brasileiro De Ficologia, May 28, 2012

Infeccoes causadas pelo virus herpes simplex tipo 1 (HSV-1) incidem sobre consideravel parcela d... more Infeccoes causadas pelo virus herpes simplex tipo 1 (HSV-1) incidem sobre consideravel parcela da populacao humana mundial, atingindo indices de ate 90%. Nao existe cura para a infeccao pelo HSV-1, cujas cepas, por vezes, sao resistentes as terapias existentes. Cyanobacteria tem se mostrado potencial fonte de farmacos o que levou-nos, neste estudo, a avaliacao da citotoxicidade e da atividade inibitoria, frente ao HSV-1, dos extratos metanolicos (EM) e em acido acetico 0,1M (EHAc) das cianobacterias Rhabdoderma sp. CCIBt773, Geitlerinema unigranulatum CCIBt971 e Phormidium sp. CCIBt1018. Para detectar alteracoes morfologicas celulares, determinar a concentracao maxima nao toxica (CMNT) e o efeito na viabilidade celular (CC 50 ) dos diferentes extratos, foram empregadas celulas Vero. Foram determinados os titulos virais, o indice de inibicao viral (IIV) e a porcentagem de Inibicao (PI) dos extratos. A partir das curvas dose-resposta, foram calculados as concentracoes capazes de inibir em 50% a replicacao viral (EC 50 ) e o indice de seletividade (IS). A toxicidade para celulas Vero (alteracoes morfologicas) variou entre 62,5 e 500mg/mL, nao sendo observada diferenca significativa entre os extratos EM e EHAc. Quanto a viabilidade, com excecao do EM de CCIBt971, que apresentou CC 50 =455µg/mL, todos os extratos mostraram CC 50 superiores a maior concentracao avaliada (500µg/mL). O EM de CCIBt971 inibiu em 99,9%, com EC 50 =25µg/mL e IS=18,2 e o EHAc, em 60,2%, com EC 50 =26µg/mL e IS>8,7. O EM de CCIBt773, inibiu em 99,8% a propagacao viral com EC 50 =141µg/mL e IS>3,5, enquanto o EHAc inibiu em 82,2%, com EC 50 =34µg/mL e IS >14,7. Em relacao a CCIBt1018, o EM mostrou inibicao de 82,2%, com EC 50 =52µg/mL e IS > 9,6 e o EHAc apresentou inibicao de 96% e EC 50 =383µg/mL e IS>1,3. Cinco dos seis extratos inibiram em mais de 80% a propagacao viral; este e os demais resultados obtidos indicam o potencial efeito anti HSV-1 destes extratos e justificam a continuacao destes estudos.

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Research paper thumbnail of Histopathological evaluation of injected mice with extracts of two toxic cyanobacteria strains

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Research paper thumbnail of Overview of the taxonomy and of the major secondary metabolites and their biological activities related to human health of the Laurencia complex (Ceramiales, Rhodophyta) from Brazil

Revista Brasileira de Farmacognosia, 2011

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Research paper thumbnail of Cyanobacterial occurrence and detection of microcystin by planar chromatography in surface water of Billings and Guarapiranga Reservoirs, SP, Brazil

Revista Brasileira de Botânica, 2007

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Research paper thumbnail of Analysis of the Toxicity and Histopathology Induced by the Oral Administration of Pseudanabaena galeata and Geitlerinema splendidum (Cyanobacteria) Extracts to Mice

Marine Drugs, 2014

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Research paper thumbnail of Biologically active compounds from cyanobacteria extracts:in vivo and in vitro aspects

Revista Brasileira de Farmacognosia, 2013

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Research paper thumbnail of Inflammatory effects of the toxic cyanobacterium Geitlerinema amphibium

Toxicon : official journal of the International Society on Toxinology, 2011

Toxic cyanobacteria in public water reservoirs may cause severe health issues for livestock and h... more Toxic cyanobacteria in public water reservoirs may cause severe health issues for livestock and human beings. Geitlerinema amphibium, which is frequently found in São Paulo City's drinking water supplies, showed toxicity in the standard mouse bioassay, while displaying signs of intoxication and post-mortem findings different from those showed by animals intoxicated by known cyanotoxins. We report here the alterations caused by G. amphibium methanolic extract on mouse microcirculatory network, as seen by in vivo intravital microscopy, besides observations on leukocyte migration, cytokine quantitation, and results of toxicological essays. Our data showed that G. amphibium methanolic extract displayed time- and dose-dependent pro-inflammatory activity, and that at lower doses [125 and 250 mg/kg body weight (b.w.)] increased the leukocyte rolling, caused partial venular stasis, as well as induced an increase in leukocyte counts in the peripheral blood and peritoneal washings. At hi...

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Research paper thumbnail of Review of toxic species of Cyanobacteria in Brazil

Algological Studies, 2008

Page 1. Review of toxic species of Cyanobacteria in Brazil CÉLIA L. SANT'ANNA1, ... more Page 1. Review of toxic species of Cyanobacteria in Brazil CÉLIA L. SANT'ANNA1, MARIA TERESA DE P. AZEVEDO1, VERA R. WERNER2, CAMILA R. DOGO1, FERNANDA R. RIOS1 and LUCIANA R. DE CARVALHO1 1Instituto ...

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Research paper thumbnail of Inflammatory effects of the toxic cyanobacterium Geitlerinema amphibium

Toxicon

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Research paper thumbnail of Highly Toxic Microcystis aeruginosa Strain, Isolated from São Paulo—Brazil, Produce Hepatotoxins and Paralytic Shellfish Poison Neurotoxins

Neurotoxicity Research, 2011

While evaluating several laboratory-cultured cyanobacteria strains for the presence of paralytic ... more While evaluating several laboratory-cultured cyanobacteria strains for the presence of paralytic shellfish poison neurotoxins, the hydrophilic extract of Microcystis aeruginosa strain SPC777—isolated from Billings’s reservoir, São Paulo, Brazil—was found to exhibit lethal neurotoxic effect in mouse bioassay. The in vivo test showed symptoms that unambiguously were those produced by PSP. In order to identify the presence of neurotoxins, cells were lyophilized, and the extracts were analyzed by HPLC–FLD and HPLC–MS. HPLC–FLD analysis revealed four main Gonyautoxins: GTX4(47.6%), GTX2(29.5%), GTX1(21.9%), and GTX3(1.0%). HPLC–MS analysis, on other hand, confirmed both epimers, with positive Zwitterions M+ 395.9 m/z for GTX3/GTX2 and M+ 411 m/z for GTX4/GTX1 epimers. The hepatotoxins (Microcystins) were also evaluated by ELISA and HPLC–MS analyses. Positive immunoreaction was observed by ELISA assay. Alongside, the HPLC–MS analyses revealed the presence of [l-ser7] MCYST-RR. The N-methyltransferase (NMT) domain of the microcystin synthetase gene mcyA was chosen as the target sequence to detect the presence of the mcy gene cluster. PCR amplification of the NMT domain, using the genomic DNA of the SPC777 strain and the MSF/MSR primer set, resulted in the expected 1,369 bp product. The phylogenetic analyses grouped the NMT sequence with the NMT sequences of other known Microcystis with high bootstrap support. The taxonomical position of M. aeruginosa SPC777 was confirmed by a detailed morphological description and a phylogenetic analysis of 16S rRNA gene sequence. Therefore, co-production of PSP neurotoxins and microcystins by an isolated M. aeruginosa strain is hereby reported for the first time.

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Research paper thumbnail of A toxic cyanobacterial bloom in an urban coastal lake, Rio Grande do Sul state, Southern Brazil

Brazilian Journal of Microbiology, 2008

Reports of cyanobacterial blooms developing worldwide have considerably increased, and, in most c... more Reports of cyanobacterial blooms developing worldwide have considerably increased, and, in most cases, the predominant toxins are microcystins. The present study reports a cyanobacterial bloom in Lake Violão, Torres, Rio Grande do Sul State, in January 2005. Samples collected on January 13, 2005, were submitted to taxonomical, toxicological, and chemical studies. The taxonomical analysis showed many different species of cyanobacteria, and that Microcystis protocystis and Sphaerocavum cf. brasiliense were dominant. Besides these, Microcystis panniformis, Anabaena oumiana,Cylindrospermopsis raciborskii, and Anabaenopsis elenkinii f. circularis were also present. The toxicity of the bloom was confirmed through intraperitoneal tests in mice, and chemical analyses of bloom extracts showed that the major substance was anabaenopeptin F, followed by anabaenopeptin B, microcystin-LR, and microcystin-RR.

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Research paper thumbnail of Review of toxic species of Cyanobacteria in Brazil

Algological Studies, 2008

Page 1. Review of toxic species of Cyanobacteria in Brazil CÉLIA L. SANT'ANNA1, ... more Page 1. Review of toxic species of Cyanobacteria in Brazil CÉLIA L. SANT'ANNA1, MARIA TERESA DE P. AZEVEDO1, VERA R. WERNER2, CAMILA R. DOGO1, FERNANDA R. RIOS1 and LUCIANA R. DE CARVALHO1 1Instituto ...

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Research paper thumbnail of Inflammatory effects of the toxic cyanobacterium Geitlerinema amphibium

Toxicon

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Research paper thumbnail of Highly Toxic Microcystis aeruginosa Strain, Isolated from São Paulo—Brazil, Produce Hepatotoxins and Paralytic Shellfish Poison Neurotoxins

Neurotoxicity Research, 2011

While evaluating several laboratory-cultured cyanobacteria strains for the presence of paralytic ... more While evaluating several laboratory-cultured cyanobacteria strains for the presence of paralytic shellfish poison neurotoxins, the hydrophilic extract of Microcystis aeruginosa strain SPC777—isolated from Billings’s reservoir, São Paulo, Brazil—was found to exhibit lethal neurotoxic effect in mouse bioassay. The in vivo test showed symptoms that unambiguously were those produced by PSP. In order to identify the presence of neurotoxins, cells were lyophilized, and the extracts were analyzed by HPLC–FLD and HPLC–MS. HPLC–FLD analysis revealed four main Gonyautoxins: GTX4(47.6%), GTX2(29.5%), GTX1(21.9%), and GTX3(1.0%). HPLC–MS analysis, on other hand, confirmed both epimers, with positive Zwitterions M+ 395.9 m/z for GTX3/GTX2 and M+ 411 m/z for GTX4/GTX1 epimers. The hepatotoxins (Microcystins) were also evaluated by ELISA and HPLC–MS analyses. Positive immunoreaction was observed by ELISA assay. Alongside, the HPLC–MS analyses revealed the presence of [l-ser7] MCYST-RR. The N-methyltransferase (NMT) domain of the microcystin synthetase gene mcyA was chosen as the target sequence to detect the presence of the mcy gene cluster. PCR amplification of the NMT domain, using the genomic DNA of the SPC777 strain and the MSF/MSR primer set, resulted in the expected 1,369 bp product. The phylogenetic analyses grouped the NMT sequence with the NMT sequences of other known Microcystis with high bootstrap support. The taxonomical position of M. aeruginosa SPC777 was confirmed by a detailed morphological description and a phylogenetic analysis of 16S rRNA gene sequence. Therefore, co-production of PSP neurotoxins and microcystins by an isolated M. aeruginosa strain is hereby reported for the first time.

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Research paper thumbnail of A toxic cyanobacterial bloom in an urban coastal lake, Rio Grande do Sul state, Southern Brazil

Brazilian Journal of Microbiology, 2008

Reports of cyanobacterial blooms developing worldwide have considerably increased, and, in most c... more Reports of cyanobacterial blooms developing worldwide have considerably increased, and, in most cases, the predominant toxins are microcystins. The present study reports a cyanobacterial bloom in Lake Violão, Torres, Rio Grande do Sul State, in January 2005. Samples collected on January 13, 2005, were submitted to taxonomical, toxicological, and chemical studies. The taxonomical analysis showed many different species of cyanobacteria, and that Microcystis protocystis and Sphaerocavum cf. brasiliense were dominant. Besides these, Microcystis panniformis, Anabaena oumiana,Cylindrospermopsis raciborskii, and Anabaenopsis elenkinii f. circularis were also present. The toxicity of the bloom was confirmed through intraperitoneal tests in mice, and chemical analyses of bloom extracts showed that the major substance was anabaenopeptin F, followed by anabaenopeptin B, microcystin-LR, and microcystin-RR.

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Research paper thumbnail of Isolation and structural characterization of microcystin-LR and three minor oligopeptides simultaneously produced by Radiocystis feernandoi (Chroococcales, Cyanobacteriae): A Brazilian toxic cyanobacterium

Toxicon, 2006

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Research paper thumbnail of Avaliação de atividade fungitóxica e isolamento de aloaromadendrano - 4α, 10 β - diol em Hypericum cordatum

Revista Brasileira de Plantas Medicinais, 2014

Hypericum cordatum é uma espécie do cerrado que foi selecionada em triagem de plantas com ativida... more Hypericum cordatum é uma espécie do cerrado que foi selecionada em triagem de plantas com atividade fungitóxica. O objetivo do presente trabalho foi isolar e identificar compostos com atividade antifúngica em extratos de folhas em diclorometano. O pó das folhas das plantas foi submetido à extração exaustiva com éter de petróleo e diclorometano. O extrato em diclorometano, e as frações ativas, foram submetidos à fracionamentos biomonitorados em coluna de Sephadex LH-20, respectivamente, com os eluentes clorofórmio:metanol (1:1) e com um gradiente de hexano:diclorometano (1:4); diclorometano:acetona (3:2 e 1:4), metanol, e água. As frações que mostraram atividade foram submetidas à cromatografia em camada delgada preparativa de sílica gel GF254, sendo que o material de maior massa foi analisado em CLAE semipreparativa. A fração ativa foi analisada por RMN de ¹H, tendo sido identificado o aloaromadendrano - 4α -10β - diol como componente principal da fração. Conclui-se, portanto, que e...

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Research paper thumbnail of The influence of temperature on Radiocystis fernandoi strain (cyanobacteria) growth and microcystin production

Brazilian Journal of Botany, 2018

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Research paper thumbnail of Article Analysis of the Toxicity and Histopathology Induced by the Oral Administration of Pseudanabaena galeata and Geitlerinema splendidum (Cyanobacteria) Extracts to Mice

marine drugs

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Research paper thumbnail of Dichotomaria marginata (Rhodophyta) as a bioindicator for marine pollution: An overview about its metabolites and adsorbed pollutants

Revista de Biología Marina y Oceanografía, 2020

Macroalgae are considered bioindicators for marine pollution, because they have the ability to qu... more Macroalgae are considered bioindicators for marine pollution, because they have the ability to quickly react to changes in their environment. In consequence, macroalgae populations fluctuate, according to species characteristics and adaptive strategies. Their cell wall polysaccharides contain sulfate groups that are capable of retaining and accumulating heavy metals. In addition to traditional contaminants, emerging pollutants are being recognized in aquatic environments. Herein, emerging pollutants have been identified after being desorbed from the macroalga Dichotomaria marginata, collected from Fortaleza Beach, Ubatuba -SP, Brazil. Based on that algal polysaccharide networks have the potential of forming hydrogen bonds with polar compounds, it was hypothesized that these pollutants would be bound to sugar polymers. Compounds present in the D. marginata samples were identified using both gas and liquid chromatography/mass spectrometry (GC/MS and HPLC/MS), assisted by computational...

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Research paper thumbnail of Efeito inibitório de extratos de cianobactérias frente ao vírus Herpes simplex tipo 1

Xiv Congresso Brasileiro De Ficologia, May 28, 2012

Infeccoes causadas pelo virus herpes simplex tipo 1 (HSV-1) incidem sobre consideravel parcela d... more Infeccoes causadas pelo virus herpes simplex tipo 1 (HSV-1) incidem sobre consideravel parcela da populacao humana mundial, atingindo indices de ate 90%. Nao existe cura para a infeccao pelo HSV-1, cujas cepas, por vezes, sao resistentes as terapias existentes. Cyanobacteria tem se mostrado potencial fonte de farmacos o que levou-nos, neste estudo, a avaliacao da citotoxicidade e da atividade inibitoria, frente ao HSV-1, dos extratos metanolicos (EM) e em acido acetico 0,1M (EHAc) das cianobacterias Rhabdoderma sp. CCIBt773, Geitlerinema unigranulatum CCIBt971 e Phormidium sp. CCIBt1018. Para detectar alteracoes morfologicas celulares, determinar a concentracao maxima nao toxica (CMNT) e o efeito na viabilidade celular (CC 50 ) dos diferentes extratos, foram empregadas celulas Vero. Foram determinados os titulos virais, o indice de inibicao viral (IIV) e a porcentagem de Inibicao (PI) dos extratos. A partir das curvas dose-resposta, foram calculados as concentracoes capazes de inibir em 50% a replicacao viral (EC 50 ) e o indice de seletividade (IS). A toxicidade para celulas Vero (alteracoes morfologicas) variou entre 62,5 e 500mg/mL, nao sendo observada diferenca significativa entre os extratos EM e EHAc. Quanto a viabilidade, com excecao do EM de CCIBt971, que apresentou CC 50 =455µg/mL, todos os extratos mostraram CC 50 superiores a maior concentracao avaliada (500µg/mL). O EM de CCIBt971 inibiu em 99,9%, com EC 50 =25µg/mL e IS=18,2 e o EHAc, em 60,2%, com EC 50 =26µg/mL e IS>8,7. O EM de CCIBt773, inibiu em 99,8% a propagacao viral com EC 50 =141µg/mL e IS>3,5, enquanto o EHAc inibiu em 82,2%, com EC 50 =34µg/mL e IS >14,7. Em relacao a CCIBt1018, o EM mostrou inibicao de 82,2%, com EC 50 =52µg/mL e IS > 9,6 e o EHAc apresentou inibicao de 96% e EC 50 =383µg/mL e IS>1,3. Cinco dos seis extratos inibiram em mais de 80% a propagacao viral; este e os demais resultados obtidos indicam o potencial efeito anti HSV-1 destes extratos e justificam a continuacao destes estudos.

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Research paper thumbnail of Histopathological evaluation of injected mice with extracts of two toxic cyanobacteria strains

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Research paper thumbnail of Overview of the taxonomy and of the major secondary metabolites and their biological activities related to human health of the Laurencia complex (Ceramiales, Rhodophyta) from Brazil

Revista Brasileira de Farmacognosia, 2011

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Research paper thumbnail of Cyanobacterial occurrence and detection of microcystin by planar chromatography in surface water of Billings and Guarapiranga Reservoirs, SP, Brazil

Revista Brasileira de Botânica, 2007

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Research paper thumbnail of Analysis of the Toxicity and Histopathology Induced by the Oral Administration of Pseudanabaena galeata and Geitlerinema splendidum (Cyanobacteria) Extracts to Mice

Marine Drugs, 2014

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Research paper thumbnail of Biologically active compounds from cyanobacteria extracts:in vivo and in vitro aspects

Revista Brasileira de Farmacognosia, 2013

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Research paper thumbnail of Inflammatory effects of the toxic cyanobacterium Geitlerinema amphibium

Toxicon : official journal of the International Society on Toxinology, 2011

Toxic cyanobacteria in public water reservoirs may cause severe health issues for livestock and h... more Toxic cyanobacteria in public water reservoirs may cause severe health issues for livestock and human beings. Geitlerinema amphibium, which is frequently found in São Paulo City's drinking water supplies, showed toxicity in the standard mouse bioassay, while displaying signs of intoxication and post-mortem findings different from those showed by animals intoxicated by known cyanotoxins. We report here the alterations caused by G. amphibium methanolic extract on mouse microcirculatory network, as seen by in vivo intravital microscopy, besides observations on leukocyte migration, cytokine quantitation, and results of toxicological essays. Our data showed that G. amphibium methanolic extract displayed time- and dose-dependent pro-inflammatory activity, and that at lower doses [125 and 250 mg/kg body weight (b.w.)] increased the leukocyte rolling, caused partial venular stasis, as well as induced an increase in leukocyte counts in the peripheral blood and peritoneal washings. At hi...

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Research paper thumbnail of Review of toxic species of Cyanobacteria in Brazil

Algological Studies, 2008

Page 1. Review of toxic species of Cyanobacteria in Brazil CÉLIA L. SANT'ANNA1, ... more Page 1. Review of toxic species of Cyanobacteria in Brazil CÉLIA L. SANT'ANNA1, MARIA TERESA DE P. AZEVEDO1, VERA R. WERNER2, CAMILA R. DOGO1, FERNANDA R. RIOS1 and LUCIANA R. DE CARVALHO1 1Instituto ...

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Research paper thumbnail of Inflammatory effects of the toxic cyanobacterium Geitlerinema amphibium

Toxicon

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Research paper thumbnail of Highly Toxic Microcystis aeruginosa Strain, Isolated from São Paulo—Brazil, Produce Hepatotoxins and Paralytic Shellfish Poison Neurotoxins

Neurotoxicity Research, 2011

While evaluating several laboratory-cultured cyanobacteria strains for the presence of paralytic ... more While evaluating several laboratory-cultured cyanobacteria strains for the presence of paralytic shellfish poison neurotoxins, the hydrophilic extract of Microcystis aeruginosa strain SPC777—isolated from Billings’s reservoir, São Paulo, Brazil—was found to exhibit lethal neurotoxic effect in mouse bioassay. The in vivo test showed symptoms that unambiguously were those produced by PSP. In order to identify the presence of neurotoxins, cells were lyophilized, and the extracts were analyzed by HPLC–FLD and HPLC–MS. HPLC–FLD analysis revealed four main Gonyautoxins: GTX4(47.6%), GTX2(29.5%), GTX1(21.9%), and GTX3(1.0%). HPLC–MS analysis, on other hand, confirmed both epimers, with positive Zwitterions M+ 395.9 m/z for GTX3/GTX2 and M+ 411 m/z for GTX4/GTX1 epimers. The hepatotoxins (Microcystins) were also evaluated by ELISA and HPLC–MS analyses. Positive immunoreaction was observed by ELISA assay. Alongside, the HPLC–MS analyses revealed the presence of [l-ser7] MCYST-RR. The N-methyltransferase (NMT) domain of the microcystin synthetase gene mcyA was chosen as the target sequence to detect the presence of the mcy gene cluster. PCR amplification of the NMT domain, using the genomic DNA of the SPC777 strain and the MSF/MSR primer set, resulted in the expected 1,369 bp product. The phylogenetic analyses grouped the NMT sequence with the NMT sequences of other known Microcystis with high bootstrap support. The taxonomical position of M. aeruginosa SPC777 was confirmed by a detailed morphological description and a phylogenetic analysis of 16S rRNA gene sequence. Therefore, co-production of PSP neurotoxins and microcystins by an isolated M. aeruginosa strain is hereby reported for the first time.

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Research paper thumbnail of A toxic cyanobacterial bloom in an urban coastal lake, Rio Grande do Sul state, Southern Brazil

Brazilian Journal of Microbiology, 2008

Reports of cyanobacterial blooms developing worldwide have considerably increased, and, in most c... more Reports of cyanobacterial blooms developing worldwide have considerably increased, and, in most cases, the predominant toxins are microcystins. The present study reports a cyanobacterial bloom in Lake Violão, Torres, Rio Grande do Sul State, in January 2005. Samples collected on January 13, 2005, were submitted to taxonomical, toxicological, and chemical studies. The taxonomical analysis showed many different species of cyanobacteria, and that Microcystis protocystis and Sphaerocavum cf. brasiliense were dominant. Besides these, Microcystis panniformis, Anabaena oumiana,Cylindrospermopsis raciborskii, and Anabaenopsis elenkinii f. circularis were also present. The toxicity of the bloom was confirmed through intraperitoneal tests in mice, and chemical analyses of bloom extracts showed that the major substance was anabaenopeptin F, followed by anabaenopeptin B, microcystin-LR, and microcystin-RR.

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Research paper thumbnail of Review of toxic species of Cyanobacteria in Brazil

Algological Studies, 2008

Page 1. Review of toxic species of Cyanobacteria in Brazil CÉLIA L. SANT'ANNA1, ... more Page 1. Review of toxic species of Cyanobacteria in Brazil CÉLIA L. SANT'ANNA1, MARIA TERESA DE P. AZEVEDO1, VERA R. WERNER2, CAMILA R. DOGO1, FERNANDA R. RIOS1 and LUCIANA R. DE CARVALHO1 1Instituto ...

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Research paper thumbnail of Inflammatory effects of the toxic cyanobacterium Geitlerinema amphibium

Toxicon

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Research paper thumbnail of Highly Toxic Microcystis aeruginosa Strain, Isolated from São Paulo—Brazil, Produce Hepatotoxins and Paralytic Shellfish Poison Neurotoxins

Neurotoxicity Research, 2011

While evaluating several laboratory-cultured cyanobacteria strains for the presence of paralytic ... more While evaluating several laboratory-cultured cyanobacteria strains for the presence of paralytic shellfish poison neurotoxins, the hydrophilic extract of Microcystis aeruginosa strain SPC777—isolated from Billings’s reservoir, São Paulo, Brazil—was found to exhibit lethal neurotoxic effect in mouse bioassay. The in vivo test showed symptoms that unambiguously were those produced by PSP. In order to identify the presence of neurotoxins, cells were lyophilized, and the extracts were analyzed by HPLC–FLD and HPLC–MS. HPLC–FLD analysis revealed four main Gonyautoxins: GTX4(47.6%), GTX2(29.5%), GTX1(21.9%), and GTX3(1.0%). HPLC–MS analysis, on other hand, confirmed both epimers, with positive Zwitterions M+ 395.9 m/z for GTX3/GTX2 and M+ 411 m/z for GTX4/GTX1 epimers. The hepatotoxins (Microcystins) were also evaluated by ELISA and HPLC–MS analyses. Positive immunoreaction was observed by ELISA assay. Alongside, the HPLC–MS analyses revealed the presence of [l-ser7] MCYST-RR. The N-methyltransferase (NMT) domain of the microcystin synthetase gene mcyA was chosen as the target sequence to detect the presence of the mcy gene cluster. PCR amplification of the NMT domain, using the genomic DNA of the SPC777 strain and the MSF/MSR primer set, resulted in the expected 1,369 bp product. The phylogenetic analyses grouped the NMT sequence with the NMT sequences of other known Microcystis with high bootstrap support. The taxonomical position of M. aeruginosa SPC777 was confirmed by a detailed morphological description and a phylogenetic analysis of 16S rRNA gene sequence. Therefore, co-production of PSP neurotoxins and microcystins by an isolated M. aeruginosa strain is hereby reported for the first time.

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Research paper thumbnail of A toxic cyanobacterial bloom in an urban coastal lake, Rio Grande do Sul state, Southern Brazil

Brazilian Journal of Microbiology, 2008

Reports of cyanobacterial blooms developing worldwide have considerably increased, and, in most c... more Reports of cyanobacterial blooms developing worldwide have considerably increased, and, in most cases, the predominant toxins are microcystins. The present study reports a cyanobacterial bloom in Lake Violão, Torres, Rio Grande do Sul State, in January 2005. Samples collected on January 13, 2005, were submitted to taxonomical, toxicological, and chemical studies. The taxonomical analysis showed many different species of cyanobacteria, and that Microcystis protocystis and Sphaerocavum cf. brasiliense were dominant. Besides these, Microcystis panniformis, Anabaena oumiana,Cylindrospermopsis raciborskii, and Anabaenopsis elenkinii f. circularis were also present. The toxicity of the bloom was confirmed through intraperitoneal tests in mice, and chemical analyses of bloom extracts showed that the major substance was anabaenopeptin F, followed by anabaenopeptin B, microcystin-LR, and microcystin-RR.

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Research paper thumbnail of Isolation and structural characterization of microcystin-LR and three minor oligopeptides simultaneously produced by Radiocystis feernandoi (Chroococcales, Cyanobacteriae): A Brazilian toxic cyanobacterium

Toxicon, 2006

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