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1.
Braz. j. biol ; 78(4): 718-727, Nov. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951607

RESUMO

Abstract In this work we have assessed the decolorization of textile effluents throughout their treatment in a solid-state fermentation (SSF) system. SSF assays were conducted with peach-palm (Bactris gasipaes) residue using the white rot fungus Ganoderma lucidum EF 31. The influence of the dye concentration and of the amounts of peach-palm residue and liquid phase on both the discoloration efficiency and enzyme production was studied. According to our results, independently of experimental conditions employed, laccase was the main ligninolytic enzyme produced by G. lucidum. The highest laccase activity was obtained at very low effluent concentrations, suggesting the existence of an inhibitory effect of higher concentrations on fungal metabolism. The highest percentage of color removal was reached when 10 grams of peach palm residue was moistened with 60 mL of the final effluent. In control tests carried out with the synthetic dye Remazol Brilliant Blue R (RBBR) decolorization efficiencies about 20% higher than that achieved with the industrial effluent were achieved. The adsorption of RBBR on peach-palm residue was also investigated. Equilibrium tests showed that the adsorption of this dye followed both Langmuir and Freundlich isotherms. Hence, our experimental results indicate that peach-palm residue is suitable substrate for both laccase production and color removal in industrial effluents.


Resumo Neste trabalho, avaliamos a descoloração de efluentes têxteis durante seu tratamento em um sistema de fermentação em estado sólido (SSF). Os ensaios foram conduzidos com resíduo de pupunha (Bactris gasipaes) utilizando o fungo de podridão branca Ganoderma lucidum EF 31. A influência da concentração de corante, as quantidades de resíduo e da fase líquida foram estudadas tanto na eficiência de descoloração como na produção de enzima. De acordo com os resultados, independentemente das condições experimentais utilizadas, a lacase foi a principal enzima ligninolítica produzida por G. lucidum. A atividade de lacase mais elevada foi obtida em baixas concentrações de efluentes, sugerindo um efeito inibitório no metabolismo fúngico. A maior remoção de cor foi obtida com 10 gramas de resíduo da pupunha e 60 mL do efluente final. Nos ensaios de controle realizados com o corante sintético RBBR, foram atingidos cerca de 20% mais descoloração do que os obtidos com o efluente industrial. A adsorção de RBBR no resíduo de pupunha também foi investigada. Os testes de equilíbrio mostraram que a adsorção deste corante seguiu as isotermas de Langmuir e Freundlich. Assim, os resultados experimentais indicam que o resíduo de pupunha é um substrato adequado tanto para a produção de lacase quanto para a remoção de cor em efluentes industriais.


Assuntos
Indústria Têxtil/métodos , Biodegradação Ambiental , Reishi/enzimologia , Arecaceae/química , Lacase/química , Águas Residuárias/química , Antraquinonas , Cor , Adsorção , Corantes/química , Fermentação
2.
Braz J Biol ; 78(4): 718-727, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29451607

RESUMO

In this work we have assessed the decolorization of textile effluents throughout their treatment in a solid-state fermentation (SSF) system. SSF assays were conducted with peach-palm (Bactris gasipaes) residue using the white rot fungus Ganoderma lucidum EF 31. The influence of the dye concentration and of the amounts of peach-palm residue and liquid phase on both the discoloration efficiency and enzyme production was studied. According to our results, independently of experimental conditions employed, laccase was the main ligninolytic enzyme produced by G. lucidum. The highest laccase activity was obtained at very low effluent concentrations, suggesting the existence of an inhibitory effect of higher concentrations on fungal metabolism. The highest percentage of color removal was reached when 10 grams of peach palm residue was moistened with 60 mL of the final effluent. In control tests carried out with the synthetic dye Remazol Brilliant Blue R (RBBR) decolorization efficiencies about 20% higher than that achieved with the industrial effluent were achieved. The adsorption of RBBR on peach-palm residue was also investigated. Equilibrium tests showed that the adsorption of this dye followed both Langmuir and Freundlich isotherms. Hence, our experimental results indicate that peach-palm residue is suitable substrate for both laccase production and color removal in industrial effluents.


Assuntos
Arecaceae/química , Biodegradação Ambiental , Lacase/química , Reishi/enzimologia , Indústria Têxtil/métodos , Águas Residuárias/química , Adsorção , Antraquinonas , Cor , Corantes/química , Fermentação
3.
Braz J Biol ; 75(4): 940-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26675911

RESUMO

Lignocellulose is the most abundant environmental component and a renewable organic resource in soil. There are some filamentous fungi which developed the ability to break down and use cellulose, hemicellulose and lignin as an energy source. The objective of this research was to analyze the effect of three nitrogen resources (ammonium sulfate, saltpetre, soybean) in the holocellulolitic activity of Lentinula edodes EF 50 using as substrate sawdust E. benthamii. An experimental design mixture was applied with repetition in the central point consisting of seven treatments (T) of equal concentrations of nitrogen in ammonium sulfate, potassium nitrate and soybean. The enzymatic activity of avicelase, carboxymetilcellulase, ß-glucosidase, xylanases and manganese peroxidase was determined. The humidity, pH, water activity (aw) and qualitative analysis of mycelial growth in 8 times of cultivation were evaluated. The results showed negative effect on enzyme production in treatments with maximum concentration of ammonium sulfate and potassium nitrate. The treatments with cooked soybean flour expressed higher enzymatic activities in times of 3, 6 and 9 days of culture, except in the activity of manganese peroxidase. The highest production was observed in the treatment with ammonium sulfate, and soybean (83.86 UI.L-1) at 20 days of cultivation.


Assuntos
Biomassa , Lignina/farmacologia , Nitrogênio/metabolismo , Cogumelos Shiitake/enzimologia , Cogumelos Shiitake/crescimento & desenvolvimento , Sulfato de Amônio/metabolismo , Eucalyptus/química , Nitratos/metabolismo , Compostos de Potássio/metabolismo , Glycine max/química , Madeira/análise
4.
Braz. j. biol ; 75(4): 940-947, Nov. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-768214

RESUMO

Abstract Lignocellulose is the most abundant environmental component and a renewable organic resource in soil. There are some filamentous fungi which developed the ability to break down and use cellulose, hemicellulose and lignin as an energy source. The objective of this research was to analyze the effect of three nitrogen resources (ammonium sulfate, saltpetre, soybean) in the holocellulolitic activity of Lentinula edodes EF 50 using as substrate sawdust E. benthamii. An experimental design mixture was applied with repetition in the central point consisting of seven treatments (T) of equal concentrations of nitrogen in ammonium sulfate, potassium nitrate and soybean. The enzymatic activity of avicelase, carboxymetilcellulase, β-glucosidase, xylanases and manganese peroxidase was determined. The humidity, pH, water activity (aw) and qualitative analysis of mycelial growth in 8 times of cultivation were evaluated. The results showed negative effect on enzyme production in treatments with maximum concentration of ammonium sulfate and potassium nitrate. The treatments with cooked soybean flour expressed higher enzymatic activities in times of 3, 6 and 9 days of culture, except in the activity of manganese peroxidase. The highest production was observed in the treatment with ammonium sulfate, and soybean (83.86 UI.L–1) at 20 days of cultivation.


Resumo Lignocelulose é o componente mais abundante do meio ambiente e recurso orgânico renovável no solo. Alguns fungos filamentosos têm desenvolvido a habilidade de degradar e utilizar celulose, hemicelulose e lignina como fonte de energia. O objetivo deste trabalho foi analisar o efeito de três fontes de nitrogênio (sulfato de amônio, nitrato de potássio e farelo de soja) na atividade enzimática de Lentinula edodes EF 50 utilizando como substrato serragem de E. benthamii. Foi aplicado um planejamento experimental de mistura com três repetições no ponto central constituído de sete tratamentos (T) de iguais concentrações em nitrogênio de sulfato de amônia, nitrato de potássio e farinha de soja cozida. Foram determinadas a atividade enzimática da avicelase, carboximetilcelulase, β-glicosidase, xilanases e manganês peroxidase. Foram avaliados o teor de umidade, pH, atividade de água (aw) e análise qualitativa do crescimento micelial em 8 tempos de cultivo. Os resultados mostraram efeito negativo na produção das enzimas nos tratamentos com máxima concentração de sulfato de amônia e nitrato de potássio. Os tratamentos com farinha de soja cozida expressaram maiores atividades enzimáticas, nos tempos de 3, 6 e 9 dias de cultivo exceto na atividade do manganês peroxidase. A maior produção foi observada no tratamento com sulfato de amônia e farinha de soja cozida (83.86 UI.L–1) em 20 dias de cultivo.


Assuntos
Biomassa , Lignina/farmacologia , Nitrogênio/metabolismo , Cogumelos Shiitake/enzimologia , Cogumelos Shiitake/crescimento & desenvolvimento , Sulfato de Amônio/metabolismo , Eucalyptus/química , Nitratos/metabolismo , Compostos de Potássio/metabolismo , Glycine max/química , Madeira/análise
5.
Braz J Biol ; 74(1): 243-50, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25055110

RESUMO

The cellulase proteins have a great importance in the enzymatic hydrolysis of woody biomass. Despite of costs being a major concern, it has been a stimulus to study basidiomycetes biochemical properties which degrade lignocellulosic material and have prompted the processes' study for obtaining cellulolytic enzymes in fungi. The objective of this research was to evaluate the effects of the initial nitrogen content on (ammonium sulfate) and on sugar cane bagasse, which hereby, acts as an inducer of hydrolytic enzymes to produce cellulases and xylanases, using three Lentinula edodes (Berk.) Pegler strains as a transformation agent. A factorial design with 22 replications in the central point was conducted, varying concentrations of ammonium sulfate and sugar cane bagasse. The submerged cultures carried out in synthetic culture medium and incubated at 25°C for 7 days on an orbital shaker at 150 rpm. The total protein and cellulase activity as endoglucanase, exoglucanase and ß-glucosidase and the xylanase was also determined. The results showed that the production of hydrolytic enzymes was stimulated by the presence of high concentrations of sugar cane bagasse (30g/L), characterizing it as an inducer due to the demonstrated proportional relationship. Thus, ammonium sulfate acted as a reducing agent in the synthesis of enzymes, being the low concentrations (0.1g/L) indicated for the enzyme production system under study. Among the studied strains, the EF52 showed higher activity for xylanase, endoglucanases, ß-glucosidase and also protein.


Assuntos
Sulfato de Amônio/farmacologia , Celulose/farmacologia , Hidrolases/biossíntese , Saccharum/química , Cogumelos Shiitake/enzimologia , Fermentação
6.
Ann Trop Med Parasitol ; 95(6): 587-93, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11672464

RESUMO

A case-control study to identify the risk factors for toxoplasmic encephalitis (TE) among HIV-infected patients with latent Toxoplasma gondii infection was performed in a teaching hospital in south-eastern Brazil. Although the subjects were all positive for serum IgG antibodies to Toxoplasma, some (the cases) developed TE during routine follow-up at the hospital whereas others (the controls) did not. Adjusted odds ratios (aOR) were estimated by multiple logistic regression after controlling for potential confounders. Only 46 (22%) of the 210 cases but 93 (45%) of the 205 controls were on prophylactic regimens with co-trimoxazole [aOR = 0.30; 95% confidence interval (CI) = 0.15-0.60]. Subjects with fewer than 100 (aOR = 37.09; CI =7.49-183.67) or between 100 and 200 CD4 cells/microl (aOR = 10.20; CI =2.00-51.90) were at substantially increased risk of developing TE than those with >400 CD4 cells/microl. Although the results of preliminary, unadjusted data analysis indicated that male sex and homosexual or bisexual activity might be additional risk factors, these associations were not found to be statistically significant by multiple regression analysis. In conclusion, no risk factors for TE other than low CD4 cell counts and failure to receive prophylaxis were found among HIV-infected Brazilian patients with past exposure to Toxoplasma. Seropositive patients with CD4 cell counts above 100/microl (the point at which specific prophylaxis is usually recommended) but below 200/microl might also benefit from effective anti-TE prophylaxis.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/etiologia , Encefalite/etiologia , Toxoplasmose Cerebral/etiologia , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Adulto , Idoso , Anti-Infecciosos/uso terapêutico , Antibioticoprofilaxia , Contagem de Linfócito CD4 , Estudos de Casos e Controles , Encefalite/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Estatística como Assunto , Toxoplasmose Cerebral/tratamento farmacológico , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
7.
Rev Argent Microbiol ; 30(1): 8-12, 1998.
Artigo em Espanhol | MEDLINE | ID: mdl-9629602

RESUMO

Twenty cheese samples were collected at Blumenau (SC) and were submitted to analysis in order to verify the presence of fecal coliforms, Escherichia coli and Staphylococcus aureus. Among the 20 samples of cheese, analysis revealed that 70% and 20% respectively, were not within present legal specifications (Norma 001/87-DNVSA) for fecal coliforms and Escherichia coli. For Staphylococcus, 95% of the samples were not within present legal specifications.


Assuntos
Queijo/microbiologia , Enterobacteriaceae/isolamento & purificação , Escherichia coli/isolamento & purificação , Contaminação de Alimentos , Staphylococcus aureus/isolamento & purificação , Animais , Proteínas de Bactérias/análise , Brasil , Bovinos , Coagulase/análise , Desoxirribonucleases/análise , Staphylococcus aureus/classificação , Staphylococcus aureus/enzimologia
8.
Rev. argent. microbiol ; 30(1): 8-12, ene.-mar. 1998. tab
Artigo em Espanhol | BINACIS | ID: bin-17398

RESUMO

Muestras de queso de fabricación casera comercializadas en mercados de Blumenau (SC), fueron analizadas para determinar la presencia de coliformes fecales, Escherichia coli y Staphylococcus aureus. De las 20 muestras investigadas, 70 y 20 por ciento presentaron, respectivamente, valores de coliformes fecales y Escherichia coli fuera de los límites recomendados por la norma 001/887 de la "Divisao Nacional de VigilÔncia Sanitária de Alimentos" (DNVSA), mientras que para Staphylococcus, 95 por ciento de las muestras estuvieronn fuera de los límites (AU)


Assuntos
Contaminação de Alimentos/análise , Escherichia coli/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Queijo/microbiologia , Brasil
9.
Rev. argent. microbiol ; 30(1): 8-12, ene.-mar. 1998. tab
Artigo em Espanhol | LILACS | ID: lil-223470

RESUMO

Muestras de queso de fabricación casera comercializadas en mercados de Blumenau (SC), fueron analizadas para determinar la presencia de coliformes fecales, Escherichia coli y Staphylococcus aureus. De las 20 muestras investigadas, 70 y 20 por ciento presentaron, respectivamente, valores de coliformes fecales y Escherichia coli fuera de los límites recomendados por la norma 001/887 de la "Divisao Nacional de Vigilância Sanitária de Alimentos" (DNVSA), mientras que para Staphylococcus, 95 por ciento de las muestras estuvieronn fuera de los límites


Assuntos
Queijo/microbiologia , Contaminação de Alimentos/análise , Escherichia coli/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Brasil
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