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1.
Pap. avulsos zool ; 62: e202262059, 2022. ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1396456

Resumo

Cuticular hydrocarbons (CHCs) of most terrestrial arthropods primarily serve as a protective barrier against desiccation and infection. Throughout evolution, these compounds have acquired another fundamental function: the exchange of signals during interactions between nestmates. However, even though cuticular hydrocarbons perform a dual function in social insects, little is known about the effect(s) of one function on the other in social insects, and no study has evaluated this relationship in social wasps. Therefore, the present study tests the hypothesis that the level of aggressiveness presented during induced encounters between nestmates of Polybia paulista who were subjected to different conditions temperature is different than between nestmates who remained under the same temperature conditions. If the hypothesis is confirmed, it is likely because the cuticle of the wasps that had been exposed to temperature variation adjusted to these conditions leading them not to recognize the cuticular chemical signature of their colony. To test this hypothesis, workers were exposed to temperature variation in a BOD chamber and then subjected to encounters with workers who were maintained at a constant temperature of 24℃. We also used control groups to evaluate the effect of isolation alone among the groups. According to our results, our hypothesis was confirmed, the level of aggressiveness presented between nestmates who were exposed to temperature variation and those who remained at 24℃ was significantly higher than the levels of aggressiveness presented between nestmates who remained isolated but under constant temperature during the same period, in some cases, it was similar to the aggressiveness presented in encounters between wasps from different colonies. During these encounters, wasps performed alarm behavior, bites, and stings not seen during encounters between wasps that remained under the same temperature, but in isolated groups. The lack of aggressive behavior under isolated conditions indicates that isolation had no effect on chemical recognition signature. These results suggest that temperature variation may have caused some change in the cues that allow recognition between nestmates. On the other hand, these results were not caused by isolation or stress generated by the study design and difference in the CHC profile of workers, as described in the literature, is consistent with our results.(AU)


Assuntos
Animais , Vespas/fisiologia , Regulação da Temperatura Corporal/fisiologia , Comunicação Animal , Exoesqueleto/fisiologia
2.
Rev. Inst. Adolfo Lutz ; 78: e1779, dez. 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1489592

Resumo

A defumação é um processo rotineiramente empregado nos alimentos como técnica de conservação, e uma maneira de proporcionar as características sensoriais específicas. Entretanto, o processo pode levar à formação de hidrocarbonetos policíclicos aromáticos (HPAs), que são compostos com dois ou mais anéis aromáticos condensados, alguns deles considerados carcinogênicos, mutagênicos e teratogênicos. Estudos em diversos países indicam que a contaminação de produtos cárneos defumados por diferentes HPAs é elevada e frequente, e desta maneira pode apresentar risco à saúde humana. O Brasil tem sido um dos maiores consumidores de carne no mundo, com tendência de aumentar o consumo de alimentos processados, e não é conhecida a real exposição da população aos HPAs pela ingestão de produtos cárneos defumados. Não há dados nacionais recentes quanto à contaminação destes alimentos com estes produtos. Considerando este panorama, o presente trabalho tem como objetivo realizar a revisão das principais metodologias analíticas, dos aspectos regulatórios e dos níveis de HPAs detectados em produtos cárneos defumados. Ademais, são apresentadas as maneiras de reduzir a contaminação dos alimentos por estes compostos.


Smoking is a common process employed in food as a conservation technique, as well as to provide the specific sensory characteristics. However, the process can lead to the formation of polycyclic aromatic hydrocarbons (PAHs), which are composed of two or more fused aromatic rings, and some of them are considered carcinogenic, mutagenic and teratogenic. Studies conducted in several countries indicate that contamination of smoked meat products by different PAHs is high and frequent, and it may cause a risk to human health. Although Brazil has been one of the largest consumers of meat in the world, with a trend to increase the consumption of processed foods, it has not known the real population exposure to PAHs by consuming the smoked meat products. There is no recent national data on the contamination of these foods. Considering this scenario, this study aimed at reviewing the main analytical methodologies, the regulatory aspects and the levels of PAHs found in the smoked meat products. In addition, the forms to reduce the contamination by these compounds are presented.


Assuntos
Alimentos em Conserva/análise , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Métodos de Análise Laboratorial e de Campo , Produtos da Carne/análise , Perigo Carcinogênico , Testes de Carcinogenicidade , Testes de Mutagenicidade
3.
R. Inst. Adolfo Lutz ; 78: e1779, 2019. tab
Artigo em Português | VETINDEX | ID: vti-29724

Resumo

A defumação é um processo rotineiramente empregado nos alimentos como técnica de conservação, e uma maneira de proporcionar as características sensoriais específicas. Entretanto, o processo pode levar à formação de hidrocarbonetos policíclicos aromáticos (HPAs), que são compostos com dois ou mais anéis aromáticos condensados, alguns deles considerados carcinogênicos, mutagênicos e teratogênicos. Estudos em diversos países indicam que a contaminação de produtos cárneos defumados por diferentes HPAs é elevada e frequente, e desta maneira pode apresentar risco à saúde humana. O Brasil tem sido um dos maiores consumidores de carne no mundo, com tendência de aumentar o consumo de alimentos processados, e não é conhecida a real exposição da população aos HPAs pela ingestão de produtos cárneos defumados. Não há dados nacionais recentes quanto à contaminação destes alimentos com estes produtos. Considerando este panorama, o presente trabalho tem como objetivo realizar a revisão das principais metodologias analíticas, dos aspectos regulatórios e dos níveis de HPAs detectados em produtos cárneos defumados. Ademais, são apresentadas as maneiras de reduzir a contaminação dos alimentos por estes compostos.(AU)


Smoking is a common process employed in food as a conservation technique, as well as to provide the specific sensory characteristics. However, the process can lead to the formation of polycyclic aromatic hydrocarbons (PAHs), which are composed of two or more fused aromatic rings, and some of them are considered carcinogenic, mutagenic and teratogenic. Studies conducted in several countries indicate that contamination of smoked meat products by different PAHs is high and frequent, and it may cause a risk to human health. Although Brazil has been one of the largest consumers of meat in the world, with a trend to increase the consumption of processed foods, it has not known the real population exposure to PAHs by consuming the smoked meat products. There is no recent national data on the contamination of these foods. Considering this scenario, this study aimed at reviewing the main analytical methodologies, the regulatory aspects and the levels of PAHs found in the smoked meat products. In addition, the forms to reduce the contamination by these compounds are presented.(AU)


Assuntos
Produtos da Carne/análise , Alimentos em Conserva/análise , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Métodos de Análise Laboratorial e de Campo , Testes de Carcinogenicidade , Testes de Mutagenicidade , Perigo Carcinogênico
4.
Acta Sci. Biol. Sci. ; 40: e36904, 2018. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-17159

Resumo

The effect of successive soil contamination with diesel oil was evaluated on population dynamics of a bacterial consortium (Acinetobacter baumannii LBBMA 04, Pseudomonas aeruginosa LBBMA 58, Ochrobactrum anthropi LBBMA 88b, Acinetobacter baumannii LBBMAES11, and Bacillus subtilis LBBMA 155) and on biodegradation of petroleum hydrocarbons (n-C12-C22). After each contamination with diesel oil, soil samples were collected for assessment of bacterial population and sequence of petroleum hydrocarbons degradation. At 20 and 40 days, the highest percentage of degradation was observed for the higher carbon chain hydrocarbons (n-C21 and C22). After the third contamination, there was a considerable reduction of n-C21degradation and a high degradation of hydrocarbons n-C13-15, C17 and C19, which contrasts with the low values of degradation of these hydrocarbons in the two previous phases. The highest growth rate of all members of the consortium occurred from 0 to 20 days, but population increase continued up to the end of the experiment (except for B. subitillis strain, whose population stabilized after 20 days). Our results show that the recurrent contamination by hydrocarbons affected the population structure of bacterial consortium and increased the total population density of the bacterial consortium.(AU)


O efeito da contaminação do solo com óleo diesel foi avaliado sobre a dinâmica populacional bacteriana de um consórcio (Acinetobacter baumannii LBBMA 04, Pseudomonas aeruginosa LBBMA 58, Ochrobactrum anthropi LBBMA 88b, Acinetobacter baumannii LBBMAES11 e Bacillus subtilis LBBMA 155) e sobre a biodegradação de hidrocarbonetos de petróleo (n-C12-C22). Após cada evento de contaminação com óleo diesel, foram coletadas amostras de solo para avaliação das populações bacterianas e da sequência de degradação de hidrocarbonetos de petróleo. Aos 20 e 40 dias, a maior porcentagem de degradação foi observada para os hidrocarbonetos de cadeia de carbono mais elevada (n-C21 e C22). Após a terceira contaminação, houve redução considerável da degradação de n-C21 e alta degradação dos hidrocarbonetos n-C13-15, C17 e C19, o que contrasta com os baixos valores de degradação desses hidrocarbonetos nas duas fases anteriores. A maior taxa de crescimento de todos os membros do consórcio ocorreu entre 0 e 20 dias, mas o aumento populacional continuou até o final do experimento (com exceção da linhagem B. subitilis, cuja população se estabilizou após 20 dias). Os resultados mostram que a contaminação sucessiva do solo com óleo diesel afetou a estrutura populacional do consórcio bacteriano e proporcionou aumento da densidade populacional total das bactérias.(AU)

5.
Acta sci., Biol. sci ; 40: e36904, 20180000. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460841

Resumo

The effect of successive soil contamination with diesel oil was evaluated on population dynamics of a bacterial consortium (Acinetobacter baumannii LBBMA 04, Pseudomonas aeruginosa LBBMA 58, Ochrobactrum anthropi LBBMA 88b, Acinetobacter baumannii LBBMAES11, and Bacillus subtilis LBBMA 155) and on biodegradation of petroleum hydrocarbons (n-C12-C22). After each contamination with diesel oil, soil samples were collected for assessment of bacterial population and sequence of petroleum hydrocarbons degradation. At 20 and 40 days, the highest percentage of degradation was observed for the higher carbon chain hydrocarbons (n-C21 and C22). After the third contamination, there was a considerable reduction of n-C21degradation and a high degradation of hydrocarbons n-C13-15, C17 and C19, which contrasts with the low values of degradation of these hydrocarbons in the two previous phases. The highest growth rate of all members of the consortium occurred from 0 to 20 days, but population increase continued up to the end of the experiment (except for B. subitillis strain, whose population stabilized after 20 days). Our results show that the recurrent contamination by hydrocarbons affected the population structure of bacterial consortium and increased the total population density of the bacterial consortium.


O efeito da contaminação do solo com óleo diesel foi avaliado sobre a dinâmica populacional bacteriana de um consórcio (Acinetobacter baumannii LBBMA 04, Pseudomonas aeruginosa LBBMA 58, Ochrobactrum anthropi LBBMA 88b, Acinetobacter baumannii LBBMAES11 e Bacillus subtilis LBBMA 155) e sobre a biodegradação de hidrocarbonetos de petróleo (n-C12-C22). Após cada evento de contaminação com óleo diesel, foram coletadas amostras de solo para avaliação das populações bacterianas e da sequência de degradação de hidrocarbonetos de petróleo. Aos 20 e 40 dias, a maior porcentagem de degradação foi observada para os hidrocarbonetos de cadeia de carbono mais elevada (n-C21 e C22). Após a terceira contaminação, houve redução considerável da degradação de n-C21 e alta degradação dos hidrocarbonetos n-C13-15, C17 e C19, o que contrasta com os baixos valores de degradação desses hidrocarbonetos nas duas fases anteriores. A maior taxa de crescimento de todos os membros do consórcio ocorreu entre 0 e 20 dias, mas o aumento populacional continuou até o final do experimento (com exceção da linhagem B. subitilis, cuja população se estabilizou após 20 dias). Os resultados mostram que a contaminação sucessiva do solo com óleo diesel afetou a estrutura populacional do consórcio bacteriano e proporcionou aumento da densidade populacional total das bactérias.

6.
Acta sci., Biol. sci ; 40: 36666-36666, 20180000. map, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460820

Resumo

The Paraíba do Sul River (PSR) drainage basin in Southeastern Brazil covers one of the most industrialized and densely populated regions of the country. The impact of chemical contamination on the PSR basin seems to be more pronounced in its middle reach where a number of potentially polluting plants are located. In this study, we used hepatic EROD activity - a biomarker of exposure to CYP1A-inducing pollutants (e.g. PAHs, PCDD/Fs, PCBs) - and the incidence of micronucleated erythrocytes (Mn) in the peripheral blood - a biomarker of effects of DNA-damaging agents (e.g. PAHs) - to evaluate the effects of pollution on two native fish species, Geophagus brasiliensis and Pimelodus maculatus. Results showed that the incidence of Mn and EROD in G. brasiliensis and P. maculatus from the two most downstream sites (Três Rios Town and Piabanha River) were markedly higher than the incidence of Mn and EROD recorded in fish from the most upstream site (Funil Reservoir). Our findings are consistent with the view that CYP1A-inducing activity and increased DNA-damage are found in fish caught in sampling sites located downstream of the stretch where there are several industries that are potential sources of PAHs and CYP1A-inducing contaminants.


O rio Paraíba do Sul (RPS) drena uma das mais industrializadas e densamente povoadas áreas do sudeste do Brasil. O impacto de contaminação química no RPS parece ser mais pronunciado no segmento médio da bacia onde se localiza grande número de indústrias potencialmente poluidoras. Neste estudo, foi avaliada a atividade hepática EROD – um biomarcador de exposição a poluente indutores da CYP1A (e.g. HAPs, PCDD/Fs, PCBs) – e a incidência de eritrócitos micronucleados (Mn) no sangue periférico – um biomarcador de efeitos de agentes de danificação do DNA- (e.g. HAPs) – para avaliar o efeito de poluição sobre dois peixes nativos, Geophagus brasiliensis e Pimelodus maculatus. Os resultados apresentaram que a incidência de Mn e EROD em G. brasiliensis e P. maculatus nos dois locais no trecho mais baixo (Três Rios e rio Piabanha) foi marcadamente mais elevada do que a incidência e a atividade EROD registradas em peixes dos locais mais à montante (reservatório do Funil). Estes resultados são consistentes com a visão de que atividade indutora de CYP1A e elevadora de danos no DNA são encontradas em peixes capturados em locais abaixo do trecho onde grande número de indústrias são potenciais fontes de poluição de indutores de contaminantes HAPs e CYP1A.


Assuntos
Animais , /administração & dosagem , /análise , Peixes-Gato/genética , Perciformes/genética
7.
Acta Sci. Biol. Sci. ; 40: e36666-e36666, Jan.-Dez.2018. mapas, tab
Artigo em Inglês | VETINDEX | ID: vti-738842

Resumo

The Paraíba do Sul River (PSR) drainage basin in Southeastern Brazil covers one of the most industrialized and densely populated regions of the country. The impact of chemical contamination on the PSR basin seems to be more pronounced in its middle reach where a number of potentially polluting plants are located. In this study, we used hepatic EROD activity - a biomarker of exposure to CYP1A-inducing pollutants (e.g. PAHs, PCDD/Fs, PCBs) - and the incidence of micronucleated erythrocytes (Mn) in the peripheral blood - a biomarker of effects of DNA-damaging agents (e.g. PAHs) - to evaluate the effects of pollution on two native fish species, Geophagus brasiliensis and Pimelodus maculatus. Results showed that the incidence of Mn and EROD in G. brasiliensis and P. maculatus from the two most downstream sites (Três Rios Town and Piabanha River) were markedly higher than the incidence of Mn and EROD recorded in fish from the most upstream site (Funil Reservoir). Our findings are consistent with the view that CYP1A-inducing activity and increased DNA-damage are found in fish caught in sampling sites located downstream of the stretch where there are several industries that are potential sources of PAHs and CYP1A-inducing contaminants.(AU)


O rio Paraíba do Sul (RPS) drena uma das mais industrializadas e densamente povoadas áreas do sudeste do Brasil. O impacto de contaminação química no RPS parece ser mais pronunciado no segmento médio da bacia onde se localiza grande número de indústrias potencialmente poluidoras. Neste estudo, foi avaliada a atividade hepática EROD um biomarcador de exposição a poluente indutores da CYP1A (e.g. HAPs, PCDD/Fs, PCBs) e a incidência de eritrócitos micronucleados (Mn) no sangue periférico um biomarcador de efeitos de agentes de danificação do DNA- (e.g. HAPs) para avaliar o efeito de poluição sobre dois peixes nativos, Geophagus brasiliensis e Pimelodus maculatus. Os resultados apresentaram que a incidência de Mn e EROD em G. brasiliensis e P. maculatus nos dois locais no trecho mais baixo (Três Rios e rio Piabanha) foi marcadamente mais elevada do que a incidência e a atividade EROD registradas em peixes dos locais mais à montante (reservatório do Funil). Estes resultados são consistentes com a visão de que atividade indutora de CYP1A e elevadora de danos no DNA são encontradas em peixes capturados em locais abaixo do trecho onde grande número de indústrias são potenciais fontes de poluição de indutores de contaminantes HAPs e CYP1A.(AU)


Assuntos
Animais , Perciformes/genética , Citocromo P-450 CYP1A1/administração & dosagem , Citocromo P-450 CYP1A1/análise , Peixes-Gato/genética
8.
Braz. J. Microbiol. ; 48(2): 314-325, abr.-jun. 2017. tab, ilus, graf, mapas
Artigo em Inglês | VETINDEX | ID: vti-17527

Resumo

This study was conducted to investigate the occurrence of PAH degrading microorganisms in two river systems in the Western Cape, South Africa and their ability to degrade two PAH compounds: acenaphthene and fluorene. A total of 19 bacterial isolates were obtained from the Diep and Plankenburg rivers among which four were identified as acenaphthene and fluorene degrading isolates. In simulated batch scale experiments, the optimum temperature for efficient degradation of both compounds was determined in a shaking incubator after 14 days, testing at 25 °C, 30 °C, 35 °C, 37 °C, 38 °C, 40 °C and 45 °C followed by experiments in a Stirred Tank Bioreactor using optimum temperature profiles from the batch experiment results. All experiments were run without the addition of supplements, bulking agents, biosurfactants or any other form of biostimulants. Results showed that Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila efficiently degraded both compounds at 37 °C, 37 °C, 30 °C and 35 °C respectively. The degradation of fluorene was more efficient and rapid compared to that of acenaphthene and degradation at Stirred Tank Bioreactor scale was more efficient for all treatments. Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila degraded a mean total of 98.60%, 95.70%, 90.20% and 99.90% acenaphthene, respectively and 99.90%, 97.90%, 98.40% and 99.50% fluorene, respectively. The PAH degrading microorganisms isolated during this study significantly reduced the concentrations of acenaphthene and fluorene and may be used on a larger, commercial scale to bioremediate PAH contaminated river systems.(AU)


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Recuperação e Remediação Ambiental , Tratamento Biológico , Microrganismos Aquáticos , Poluição de Rios , África do Sul
9.
Braz. J. Microbiol. ; 47(2): 271-278, Abr-Jun. 2016. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-23404

Resumo

Members of the Sphingomonas genus are often isolated from petroleum-contaminated soils due to their unique abilities to degrade polycyclic aromatic hydrocarbons (PAHs), which are important for in situ bioremediation. In this study, a combined phenotypic and genotypic approach using streptomycin-containing medium and Sphingomonas -specific PCR was developed to isolate and identify culturable Sphingomonas strains present in petroleum-contaminated soils in the Shenfu wastewater irrigation zone. Of the 15 soil samples examined, 12 soils yielded yellow streptomycin-resistant colonies. The largest number of yellow colony-forming units (CFUs) could reach 105 CFUs g-1 soil. The number of yellow CFUs had a significant positive correlation (p 0.05) with the ratio of PAHs to total petroleum hydrocarbons (TPH), indicating that Sphingomonas may play a key role in degrading the PAH fraction of the petroleum contaminants at this site. Sixty yellow colonies were selected randomly and analyzed by colony PCR using Sphingomonas -specific primers, out of which 48 isolates had PCR-positive signals. The 48 positive amplicons generated 8 distinct restriction fragment length polymorphism (RFLP) patterns, and 7 out of 8 phylotypes were identified as Sphingomonas by 16S rRNA gene sequencing of the representative strains. Within these 7 Sphingomonas strains, 6 strains were capable of using fluorene as the sole carbon source, while 2 strains were phenanthrene-degrading Sphingomonas. To the best of our knowledge, this is the first report to evaluate the relationship between PAHs contamination levels and culturable Sphingomonas in environmental samples.(AU)


Assuntos
Sphingomonas/patogenicidade , Qualidade do Solo , Hidrocarbonetos Policíclicos Aromáticos/síntese química
10.
Zoologia (Curitiba, Impr.) ; 32(5): 351-359, Oct. 2015. tab, map
Artigo em Inglês | VETINDEX | ID: biblio-1504349

Resumo

Determining the significance of biotic and abiotic factors in the structuring of fish assemblages in freshwater environments is an important question in ecology, particularly in view of environmental changes caused by man. In this paper we sought to identify the factors responsible for the composition and abundance of fish species collected with gill nets in six locations near ports in forest clearance areas opened up for oil and natural gas exploration (Petrobras Pedro Moura Base) in the Urucu River, during drought and flood cycles. In all, 923 individuals from 23 families and 82 species were collected, totalling a biomass of 182,244 g. The most abundant species during the flood season were Bryconops alburnoides (Kner, 1858) and Dianema urostriatum (Miranda Ribeiro, 1912); in the drought season, the predominant species were Osteoglossum bicirrhosum (Cuvier, 1829) and Serrasalmus rhombeus (Linnaeus, 1766). The species with the greatest biomass during the flood season were Pellona castelnaeana (Valenciennes, 1847), S. rhombeus and Pellona flavipinis (Valenciennes, 1847). During the drought season, the predominant species was O. bicirrhosum. When both periods were analysed together, electrical conductivity, water transparency and dissolved oxygen were the most important factors. The species Hemisorubim platyrhynchos (Valenciennes, 1840), O. bicirrhosum, Chaetobranchus flavenscens Heckel, 1840, Geophagus proximus (Castelnau, 1855) were strongly related to high values of conductivity, pH and water current velocity during the drought season, as well as Serrasalmus altispinis Merckx, Jégu & Santos, 2000, Triportheus albus Cope, 1872, Triportheus angulatus (Spix & Agassiz, 1829) and Brycon melanopterus (Cope, 1872) that were associated with less depth and width in the drought season whereas P. castelnaeana, D. urostriatum, Rhytiodus argenteofuscus Kner, 1858 and Sorubim lima (Bloch & Schneider, 1801) were mainly associated with high transparency and dissolved oxygen during the flood season.


Assuntos
Animais , Exploração de Recursos Naturais , Gás Natural/efeitos adversos , Peixes , Petróleo/efeitos adversos , Poluentes Ambientais , Ecossistema Amazônico
11.
Zoologia (Curitiba) ; 32(5): 351-359, Oct. 2015. tab, mapas
Artigo em Inglês | VETINDEX | ID: vti-762330

Resumo

Determining the significance of biotic and abiotic factors in the structuring of fish assemblages in freshwater environments is an important question in ecology, particularly in view of environmental changes caused by man. In this paper we sought to identify the factors responsible for the composition and abundance of fish species collected with gill nets in six locations near ports in forest clearance areas opened up for oil and natural gas exploration (Petrobras Pedro Moura Base) in the Urucu River, during drought and flood cycles. In all, 923 individuals from 23 families and 82 species were collected, totalling a biomass of 182,244 g. The most abundant species during the flood season were Bryconops alburnoides (Kner, 1858) and Dianema urostriatum (Miranda Ribeiro, 1912); in the drought season, the predominant species were Osteoglossum bicirrhosum (Cuvier, 1829) and Serrasalmus rhombeus (Linnaeus, 1766). The species with the greatest biomass during the flood season were Pellona castelnaeana (Valenciennes, 1847), S. rhombeus and Pellona flavipinis (Valenciennes, 1847). During the drought season, the predominant species was O. bicirrhosum. When both periods were analysed together, electrical conductivity, water transparency and dissolved oxygen were the most important factors. The species Hemisorubim platyrhynchos (Valenciennes, 1840), O. bicirrhosum, Chaetobranchus flavenscens Heckel, 1840, Geophagus proximus (Castelnau, 1855) were strongly related to high values of conductivity, pH and water current velocity during the drought season, as well as Serrasalmus altispinis Merckx, Jégu & Santos, 2000, Triportheus albus Cope, 1872, Triportheus angulatus (Spix & Agassiz, 1829) and Brycon melanopterus (Cope, 1872) that were associated with less depth and width in the drought season whereas P. castelnaeana, D. urostriatum, Rhytiodus argenteofuscus Kner, 1858 and Sorubim lima (Bloch & Schneider, 1801) were mainly associated with high transparency and dissolved oxygen during the flood season.(AU)


Assuntos
Animais , Peixes , Exploração de Recursos Naturais , Petróleo/efeitos adversos , Gás Natural/efeitos adversos , Poluentes Ambientais , Ecossistema Amazônico
12.
Braz. J. Microbiol. ; 46(3): 937-941, July-Sept. 2015. ilus
Artigo em Inglês | VETINDEX | ID: vti-4491

Resumo

In this study, we evaluated the effect of low and high molecular weight polycyclic aromatic hydrocarbons (PAHs), i.e., Phenanthrene, Pyrene and Benzo[a]pyrene, on the radial growth and morphology of the PAH-degrading fungal strains Aspergillus nomius H7 and Trichoderma asperellum H15. The presence of PAHs in solid medium produced significant detrimental effects on the radial growth of A. nomius H7 at 4,000 and 6,000 mg L−1 and changes in mycelium pigmentation, abundance and sporulation ability at 1,000–6,000 mg L−1. In contrast, the radial growth of T. asperellum H15 was not affected at any of the doses tested, although sporulation was observed only up to 4,000 mg L−1 and as with the H7 strain, some visible changes in sporulation patterns and mycelium pigmentation were observed. Our results suggest that fungal strains exposed to high doses of PAHs significantly vary in their growth rates and sporulation characteristics in response to the physiological and defense mechanisms that affect both pigment production and conidiation processes. This finding is relevant for obtaining a better understanding of fungal adaptation in PAH-polluted environments and for developing and implementing adequate strategies for the remediation of contaminated soils..(AU)


Assuntos
Aspergillus/crescimento & desenvolvimento , Benzo(a)pireno/farmacologia , Micélio , Fenantrenos/farmacologia , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Pirenos/farmacologia , Esporos Fúngicos , Trichoderma/crescimento & desenvolvimento , Aspergillus , Aspergillus/metabolismo , Biodegradação Ambiental , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Microbiologia do Solo , Poluentes do Solo , Trichoderma , Trichoderma/metabolismo
13.
Tese em Português | VETTESES | ID: vtt-219340

Resumo

A intensa exploração de petróleo tem causado diversas polêmicas ambientais, principalmente em relação aos possíveis impactos nos ecossistemas aquáticos. O petróleo e seus derivados são formados por misturas complexas de hidrocarbonetos e sua composição química é totalmente dependente de sua origem geográfica e do nível de craqueamento (processamento). Os hidrocarbonetos constituem uma das classes de poluentes mais encontrados nos ambientes aquáticos. O presente trabalho avalia os efeitos da exposição à fração solúvel do petróleo, da gasolina, do óleo diesel, de dois óleos minerais e de um óleo lubrificante sobre os processos ontogenéticos de embriões, larvas e de pós-larvas do lambari Astyanax lacustris. O estudo foi conduzido em três diferentes momentos. Primeiramente definiu-se a concentração letal mediana (CL50) da do petróleo (FSAP), do diesel (FSAD), da gasolina (FSAG), de um óleo lubrificante (FSAOL) e de dois óleos minerais (FSAOM1 e FSAOM2), realizados em dois ensaios em condições controladas de laboratório, um envolvendo embriões e o outro larvas da espécie. Os experimentos foram realizados em placas de cultivo celular de 6 poços, totalizando 30 exemplares para cada concentração-teste. A FSAG foi a que apresentou a maior concentração total de hidrocarbonetos (335.543 µg L-1 ) e, ao mesmo tempo, foi a que provocou maiores danos, tanto para embriões como para larvas de A. lacustris. Os embriões se mostraram muito sensíveis à exposição aos derivados de petróleo, mesmo quando expostos a baixas concentrações. As larvas foram afetadas apenas pela exposição à FSAG e FSAP. Uma vez definido os valores da CL50 de cada um dos compostos, avaliou-se os processos ontogenéticos dos exemplares expostos ao composto mais tóxico para os embriões (FSAG), intermediário (FSAP) e pouco tóxico (FSAOM). Os exemplares foram expostos a 0,04% da FSAG, 34,7% da FSAP e 50,8% do petróleo FSAOM. A exposição, mesmo em baixas concentrações, ocasionou efeitos subletais e letais aos embriões e larvas. A FSAG foi, novamente, a que apresentou maiores concentrações de hidrocarbonetos e também a que provocou maiores danos aos organismos testados. Entre as alterações mais relatadas estão lesões nas nadadeiras e edemas cardíacos, que foram registrados em 36,7% dos exemplares expostos. A FSAP ocasionou efeitos semelhantes aos da gasolina e a FSAOM foi a que apresentou menores efeitos. Definidos as toxicidades desses derivados nas fases iniciais de vida, investigou-se os efeitos na reprodução da espécie. Juvenis foram expostos à 0,5% de FSAG, 1,7% de FSAP e a 11,2% de FSAOM por 15 dias. Ao atingirem tamanho próximo a 7,0±1,0 cm para os machos e 9,0±1,0 cm, exemplares foram selecionados ao acaso e submetidos ao processo de indução hormonal. Esse procedimento foi repetido por mais três vezes, com intervalo de 30 dias a cada evento. A exposição dos juvenis à FSAG e à FSAP apresentou maior influência sobre as taxas de sobrevivência das larvas geradas por A. lacustris. Já a fração solúvel em água do óleo mineral (FSAOM), novamente, se mostrou muito pouco tóxica para a espécie. Quanto menor foi o tempo decorrido entre a exposição e a reprodução, menor foi o número de ovócitos produzidos pelas fêmeas e maior a probabilidade de geração de embriões malformados. Entretanto, com o passar do tempo, essas diferenças foram diminuindo e decorridos 102 dias da exposição, os tratamentos não apresentavam mais diferenças reprodutivas significativas em relação ao grupo controle ou mesmo entre si.


The intense exploitation of oil has several environmental controversies, mainly in relation to the possible impacts on aquatic ecosystems. Petroleum and its derivatives are formed by mixtures of hydrocarbons and their chemical composition is totally dependent on their geographic origin and cracking level (processing). Hydrocarbons created one of the most pollutant classes found in aquatic environments. This work evaluates the effects of exposure to the fraction soluble in oil, gasoline, diesel oil, two mineral oils and a lubricating oil on the ontogenetic processes of embryos, larvae and post-larvae of tetra Astyanax lacustris. The study was conducted at three different times. Firstly, the median lethal concentration (CL50) of that of petroleum (WSFP), diesel (WSFD), gasoline (WSFG), a lubricating oil (WSFLO) and two mineral oils (WSFMO1 and WSFMO2), carried out in two tests under controlled laboratory conditions, one involving embryo and the other larvae of the species. The experiments were carried out in cell culture plates of 6 wells, totaling 30 specimens for each test concentration. WSFG was the one with the highest total hydrocarbon concentration (335.543 µg L-1 ) and, at the same time, it caused the most damage, both for embryos and larvae. Embryos were very sensitive to exposure to petroleum products, even when exposed to low concentrations. The larvae were affected only by exposure to WSFG and WSFP. Once the LC50 values of each of the compounds were defined, the ontogenetic processes of the specimens exposed to the most toxic to the embryos (WSFG), intermediate (WSFP) and low toxic (WSFMO) compounds were evaluated. The specimens were exposed to 0.04% of WSFG, 34.79% of WSFP and 50.88% of WSFMO oil. Exposure, even in low concentrations, caused sublethal and lethal effects on embryos and larvae. WSFG was, again, the one with the highest concentrations of hydrocarbons and also the one that caused the greatest damage to the organisms tested. Among the most reported alterations are lesions in the fins and cardiac edema, which were recorded in 36.7% of the exposed specimens. WSFP had similar effects to WSFG and WSFMO had the least effect. Once the toxicities of these derivatives were defined in the early stages of life, the effects on the reproduction of the species were investigated. Juveniles were exposed to 0.5% WSFG, 1.76% WSFP and 11.24% WSFMO for 15 days. When reaching a size close to 7.0 ± 1.0 cm for males and 9.0 ± 1.0 cm, specimens were selected at random and submitted to the hormonal induction process. This procedure was repeated three more times, with an interval of 30 days at each event. The exposure of juveniles to WSFG and WSFP had a greater influence on the survival rates of larvae generated by A. lacustris. The water-soluble fraction of the mineral oil (WSFMO), again, proved to be very little toxic for the species. The shorter the time elapsed between exposure and reproduction, the smaller the number of oocytes produced by the females and the greater the probability of generating malformed embryos. However, over time, these differences have diminished and after 102 days of exposure, the treatments no longer showed significant reproductive differences in relation to the control group or even among themselves

14.
Braz. j. biol ; 75(2): l4341-434, 05/2015. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468212

Resumo

Analyses of 16S rDNA genes were used to identify the microbiota isolated from the mucus of the zoanthid Palythoa caribaeorum at Porto de Galinhas on the coast of Pernambuco State, Brazil. This study is important as the first report of this association, because of the potential biotechnological applications of the bacterium Alcanivorax dieselolei, and as evidence for the presence of a hydrocarbon degrading bacterium in a reef ecosystem such as Porto de Galinhas.


Análises dos genes 16S rDNA foram empregadas para identificar a microbiota isolada do muco do zoantídeo Palythoa caribaeorum de Porto de Galinhas, litoral do estado de Pernambuco, Brasil. Este estudo é importante pelo ineditismo dessa associação, pelas relevantes aplicações biotecnológicas da bactéria Alcanivorax dieselolei e pela indicação da presença de uma bactéria degradadora de hidrocarbonetos em um ecossistema recifal como o de Porto de Galinhas.


Assuntos
Animais , Alcanivoraceae/genética , Antozoários/microbiologia , Muco/microbiologia , Alcanivoraceae/fisiologia , DNA Bacteriano/genética , /genética , Reação em Cadeia da Polimerase
15.
Braz. J. Biol. ; 75(2): l4341, 05/2015. graf
Artigo em Inglês | VETINDEX | ID: vti-17532

Resumo

Analyses of 16S rDNA genes were used to identify the microbiota isolated from the mucus of the zoanthid Palythoa caribaeorum at Porto de Galinhas on the coast of Pernambuco State, Brazil. This study is important as the first report of this association, because of the potential biotechnological applications of the bacterium Alcanivorax dieselolei, and as evidence for the presence of a hydrocarbon degrading bacterium in a reef ecosystem such as Porto de Galinhas.(AU)


Análises dos genes 16S rDNA foram empregadas para identificar a microbiota isolada do muco do zoantídeo Palythoa caribaeorum de Porto de Galinhas, litoral do estado de Pernambuco, Brasil. Este estudo é importante pelo ineditismo dessa associação, pelas relevantes aplicações biotecnológicas da bactéria Alcanivorax dieselolei e pela indicação da presença de uma bactéria degradadora de hidrocarbonetos em um ecossistema recifal como o de Porto de Galinhas.(AU)


Assuntos
Animais , Alcanivoraceae/genética , Antozoários/microbiologia , Muco/microbiologia , Alcanivoraceae/fisiologia , DNA Bacteriano/genética , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética
16.
Braz. j. microbiol ; 44(2): 595-605, 2013.
Artigo em Inglês | VETINDEX | ID: vti-971

Resumo

In situ biosurfactant (rhamnolipid) production by Pseudomonas putida CB-100 was achieved during a bioaugmented and biostimulated treatment to remove hydrocarbons from aged contaminated soil from oil well drilling operations. Rhamnolipid production and contaminant removal were determined for several treatments of irradiated and non-irradiated soils: nutrient addition (nitrogen and phosphorus), P. putida addition, and addition of both (P. putida and nutrients). The results were compared against a control treatment that consisted of adding only sterilized water to the soils. In treatment with native microorganisms (non-irradiated soils) supplemented with P. putida, the removal of total petroleum hydrocarbons (TPH) was 40.6%, the rhamnolipid production was 1.54 mg/kg, and a surface tension of 64 mN/m was observed as well as a negative correlation (R = -0.54, p < 0.019) between TPH concentration (mg/kg) and surface tension (mN/m), When both bacteria and nutrients were involved, TPH levels were lowered to 33.7%, and biosurfactant production and surface tension were 2.03 mg/kg and 67.3 mN/m, respectively. In irradiated soil treated with P. putida, TPH removal was 24.5% with rhamnolipid generation of 1.79 mg/kg and 65.6 mN/m of surface tension, and a correlation between bacterial growth and biosurfactant production (R = -0.64, p < 0.009) was observed. When the nutrients and P. putida were added, TPH removal was 61.1%, 1.85 mg/kg of biosurfactants were produced, and the surface tension was 55.6 mN/m. In summary, in irradiated and non-irradiated soils, in situ rhamnolipid production by P. putida enhanced TPH decontamination of the soil.(AU)


Assuntos
Análise do Solo , Hidrocarbonetos , Tensoativos , Poluição por Petróleo , Características do Solo , Pseudomonas putida
17.
Neotrop. ichthyol ; 11(3): 683-691, 06/2013. graf
Artigo em Inglês | VETINDEX | ID: vti-10505

Resumo

The purpose of this work was to evaluate the effects of the water-soluble fraction of gasoline (WSFG) on the Neotropical freshwater fish Prochilodus lineatus. The WSFG was prepared by mixing gasoline in water (1:4) and animals were exposed for 6, 24 and 96h to 5% diluted WSFG or only to water. After exposure, blood was collected from the caudal vein and the gills were removed. The following parameters were analyzed: hematological (hemoglobin, hematocrit, number of red blood cells), osmo-ionic (plasma Na+, Cl- and K+ and plasma osmolarity), metabolic (total plasma proteins and glucose), endocrine (cortisol), density and distribution of chloride cells [CC] in the gills (immunohistochemistry), and branchial Na+/K+-ATPase (NKA) activity. Hemolysis was found to occur after 96h exposure to WSFG, as indicated by the decrease in the hematological parameters analyzed, followed by an increase in plasma K+. Secondary stress response was revealed by the occurrence of hyperglycemia in the three periods of exposure, despite the absence of significant increases in the plasma cortisol. The exposure to WSFG also caused an increase in the quantity of CC and in plasma Na+, after 24h, as well as in the enzymatic activity of NKA and plasma osmolarity, after 24h and 96h. These results indicate that fish exposed to the WSFG showed physiological adjusts to maintain their osmotic balance. However, the increase in the quantity of CC in the lamellae may interfere in the gas exchange impairing respiration.(AU)


O objetivo deste trabalho foi avaliar os efeitos da fração solúvel da gasolina (FSG) em Prochilodus lineatus. A FSG foi preparada misturando-se a gasolina à água (1:4) e os animais foram expostos por 6, 24 e 96h à FSG diluída 5% ou apenas à água. Após a exposição, o sangue foi coletado pela veia caudal e as brânquias foram retiradas. Os seguintes parâmetros foram analisados: hematológicos (hemoglobina, hematócrito, quantidade de células vermelhas), osmo-iônicos (concentrações plasmáticas de Na+, Cl-, K+ e osmolaridade), metabólicos (concentrações plasmáticas de proteínas totais e glicose), endócrino (cortisol plasmático), densidade e distribuição de células-cloreto [CC] nas brânquias (imunohistoquímica) e a atividade da enzima Na+/K+-ATPase (NKA) branquial. Hemólise foi observada após 96h de exposição à FSG, indicada pela diminuição dos parâmetros hematológicos analisados, seguido pelo aumento do K+ plasmático. Houve resposta secundária de estresse visualizada pela ocorrência da hiperglicemia nos três tempos de exposição, apesar da ausência de diferenças significativas na concentração plasmática do cortisol. A exposição à FSG também provocou aumento na quantidade das CC e na concentração de Na+, após 24h, e na atividade enzimática da NKA e osmolaridade, após 24h e 96h. Esses resultados indicam que peixes expostos à FSG apresentaram ajustes fisiológicos para manter o equilíbrio osmótico. Entretanto, o aumento na quantidade de CC nas lamelas pode ter interferido nas trocas gasosas prejudicando a respiração.(AU)


Assuntos
Animais , Água/análise , Gasolina , Hematologia , Estresse Fisiológico , Peixes/classificação
18.
Tese em Português | VETTESES | ID: vtt-208443

Resumo

Os extratos de formigas são conhecidos por possuírem uma ampla gama de atividades biológicas. No entanto, pouco se sabe sobre os extratos não-protéicos desses animais. A espécie Odontomachus bauri é conhecida por possuir um veneno com ação proteolítica, hemolítica, coagulante, antimicrobiana e antiparasitária. No presente estudo, as formigas O. bauri coletadas em Maranguape, Ceará, foram levadas ao laboratório para a extração de metabólitos secundários por meio da imersão das formigas em hexano durante 30 minutos e, depois, em etanol, durante o período de um semana, enfatizando a remoção de hidrocarbonetos. Após este período, os insetos foram removidos por filtração e os extratos foram obtidos após a remoção dos solventes por evaporação rotativa. As amostras de extratos hexânicos foram utilizadas para a análise de cromatografia gasosa acoplada à espectrometria de massas e o extrato etanólico foi submetido à testes de citotoxicidade (Linhagens: PC-3, HCT-116 e SF-295), anti-helmínticos (Caenorhabditis elegans - cepas sensível e resistente à Ivermectina) e antimicrobianos (Cepas: Pseudomonas aeruginosa ATCC 10145, Escherichia coli ATCC 11775, Staphylococcus epidermidis ATCC 12228 e Klebsiella pneumoniae ATCC 13883). Os resultados das análises revelaram que o extrato hexânico é composto por hidrocarbonetos saturados com cadeias longas (C15-C36), sendo formado principalmente por N-Alkanes (43,7%) e Monometilalcanos (37,5%). A composição das amostras revela um padrão único para as formigas O. bauri coletadas, uma vez que diferem em tipo, quantidade e proporção em relação aos padrões observados nas outras espécies do mesmo gênero. O principal componente do extrato foi o 6-Metil-nonacosano (23,41%), o que sugere a hipótese de este ser o feromônio sexual dessa espécie. O extrato etanólico não apresentou atividade citotóxica viável contra as cepas testadas. No entanto, observou-se um efeito positivo contra as cepas bacterianas e as linhagens de nemátodos, sugerindo a existência de funções biológicas importantes relacionadas à saúde do ninho.


Ant extracts are known to have a wide range of biological activities. However, little is known about the non-protein extracts of these animals. The species Odontomachus bauri is known to have a venom with proteolytic, hemolytic, coagulant, antimicrobial and antiparasitic action. In the present study, the O. bauri ants collected in Maranguape-Ce were taken to the laboratory for the extraction of secondary metabolites by immersing the ants in hexane for 30 minutes and then in ethanol for a period of one week, emphasizing the removal of hydrocarbons. After this time, the insects were removed by filtration and the extracts were obtained after removal of the solvents by rotary evaporation. Samples of hexane extracts were used for the analysis of gas chromatography coupled to mass spectrometry and the ethanolic extract was submitted to antitumor (Lineages: PC-3, HCT-116 and SF-295), anthelmintic (Caenorhabditis elegans - Strains sensitive and resistant to Ivermectin) and antimicrobial tests (Strains: Pseudomonas aeruginosa ATCC 10145, Escherichia coli ATCC 11775, Staphylococcus epidermidis ATCC 12228 and Klebsiella pneumoniae ATCC 13883). The results of the analyzes revealed that the hexane extract is composed of saturated hydrocarbons with long chains (C15-C36), mainly formed by N-Alkanes (43.7%) and Mono-methylalcans (37.5%). The composition of the samples reveals a unique pattern for the O. bauri ants collected, since they differ in type, quantity and proportion in relation to the patterns observed in the other species of the same genus. The main component of the extract was 6-methylnonacosane (23.41%), which suggests the hypothesis of this being the sex pheromone of this species. The ethanolic extract did not present viable antitumor activity against the tested strains. However, a positive effect was observed against bacterial and nematode strains, suggesting the existence of biological functions related to nest health.

19.
Tese em Português | VETTESES | ID: vtt-205284

Resumo

O crescimento demográfico, assim como a expansão tecnológica e industrial, tem causado sérias ameaças ao ambiente aquático, principalmente nas áreas costeiras. O lançamento de dejetos provenientes das mais variadas ações antrópicas, como os provenientes da indústria do petróleo e esgoto sanitário, provoca danos aos animais aquáticos, colocam em risco a atividade de aquicultura e afeta, consequentemente, a população humana. Os dejetos lançados no ambiente, possuem uma das mais variadas e complexas misturas, rica em nutrientes e compostos químicos, podendo formar subprodutos ainda mais tóxicos ao entrarem em contato entre si. Estes compostos químicos podem provocar alterações iniciais a nível fisiológico, celular e molecular nos organismos, e desta forma, estas respostas perante aos contaminantes podem ser utilizadas como biomarcadores de contaminação aquática. Espécies de moluscos bivalves são comumente utilizados como organismos biondicadores de contaminação aquática. A vieira Nodipecten nodosus é uma espécie de importância econômica, principalmente para as regiões Sul e Sudeste do Brasil e possui características importantes como movimentação lenta e capacidade de bioacumular contaminantes em seus tecidos rapidamente. Análises enzimáticas e moleculares são empregadas para elucidação de respostas dos organismos frente à exposição aos contaminantes. O presente estudo teve como objetivo (i) avaliar a capacidade de bioacumulação e depuração das vieiras; (ii) avaliar as respostas de biomarcadores bioquímicos clássicos; (iii) analisar genes conhecidos por atuarem na biotransformação de xenobióticos e potenciais genes candidatos a novos biomarcadores de contaminação aquática em vieiras N. nodosus. Para tanto, os exemplares de vieiras foram expostos ao fenantreno e ao óleo cru. Os resultados dos biomarcadores bioquímicos e moleculares foram analisados nas brânquias, 24 e 96 h após a exposição à duas concentrações de fenantreno e 96 h após a depuração; assim, como a análise química dos tecidos, verificou a bioacumulação e eliminação da substância, após 96 h de exposição e depuração. Os resultados indicam que N. nodosus é capaz de induzir uma resposta antioxidante relacionada com a biotransformação de fenantreno, e a depuração pode ser um protocolo eficaz para bivalves após a contaminação. Além disso, os resultados referentes à exposição ao óleo cru mostraram um conjunto de 14 genes biomarcadores de contaminação aquática por hidrocarbonetos policíclicos aromáticos (HPAs), e o uso de brânquias e glândula digestiva como tecidos-alvo. Estes ensaios poderiam ser aplicados como parâmetros adicionais em programas de biomonitoramento em áreas como as de produção de petróleo ou gás natural, especialmente offshore. Isto poderia ajudar a caracterizar a possível contaminação por HPAs em tais áreas, e monitorar a persistência, o destino e os efeitos destas substâncias químicas durante e após os eventos de derramamento de óleo.


Population growth, as well as the technological and industrial expansion, has caused serious threats to the aquatic environment, especially in coastal areas. Waste release from human activities, such as oil industry and sewage treatment/discharge, causes damage to aquatic animals, put at risk aquaculture activities and affects the human population. The waste released into the environment is one of the most varied and complex mixtures, rich in nutrients and chemicals, which can form even more toxic by-products when in contact with each other. These chemicals can cause physiological, cellular and molecular changes in the organisms which can be used as biomarkers of water pollution. Bivalve mollusc species are commonly used as biondicator of water contamination. Scallops Nodipecten nodosus is a species of economic importance, especially to the south and southeast Brazil and has important features, such as low mobility and high ability to quickly bioaccumulate contaminants. Enzymatic and molecular analyses are employed to elucidate responses of organisms upon exposure to contaminants. This study aimed to (i) evaluate the bioaccumulation capacity and depuration of scallops; (ii) evaluate the responses of classical biochemical biomarkers; (iii) analyze genes known to work in the biotransformation of xenobiotics and potential candidate genes as new biomarkers of water pollution in scallops N. nodosus. Therefore, scallops were exposed to phenanthrene and crude oil. The results of biochemical and molecular biomarkers were analyzed in the gills, after 24 and 96 h of exposure to two phenanthrene concentrations and after 96 h of depuration, as well as chemical analysis of the tissues found to bioaccumulate and removal of the substance after 96 h exposure and depuration. These results indicate that N. nodosus is capable of inducing an antioxidant response related to the biotransformation of phenanthrene, and depuration can be an effective protocol for bivalve after contamination. Moreover, the results for exposure to crude oil pointed to a set of 14 genes from N. nodosus as biomarkers of aquatic contamination to polycyclic aromatic hydrocarbons (PAHs), and the use of gills and digestive gland as target tissues. These assays could be applied as additional parameters in biomonitoring programs in areas with oil and gas production or contamination, especially offshore ones. This could help to characterize possible PAHs contamination in such areas, and monitor the persistence, fate and effects of these chemical during and after oil spill events.

20.
Artigo em Inglês | VETINDEX | ID: vti-444562

Resumo

Most of our knowledge about pollutants and the way they are biodegraded in the environment has previously been shaped by laboratory studies using hydrocarbon-degrading bacterial strains isolated from polluted sites. In present study Gram-positive (Mycobacterium sp. IBB Po1, Oerskovia sp. IBB Po2, Corynebacterium sp. IBB Po3) and Gram-negative (Chryseomonas sp. IBB Po7, Pseudomonas sp. IBB Po10, Burkholderia sp. IBB Po12) bacteria, isolated from oily sludge, were found to be able to tolerate pure and mixture of saturated hydrocarbons, as well as pure and mixture of monoaromatic and polyaromatic hydrocarbons. Isolated Gram-negative bacteria were more tolerant to mixture of saturated (n-hexane, n-hexadecane, cyclohexane), monoaromatic (benzene, toluene, ethylbenzene) and polyaromatic (naphthalene, 2-methylnaphthalene, fluorene) hydrocarbons than Gram-positive bacteria. There were observed cellular and molecular modifications induced by mixture of saturated, monoaromatic and polyaromatic hydrocarbons to Gram-positive and Gram-negative bacteria. These modifications differ from one strain to another and even for the same bacterial strain, according to the nature of hydrophobic substrate.

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