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Pesquisa : G02.111.062 [Categoria DeCS]
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Id: biblio-974307
Autor: Zhang, Nan; Peng, Huijuan; Li, Yong; Yang, Wenxiu; Zou, Yuneng; Duan, Huiguo.
Título: Ammonia determines transcriptional profile of microorganisms in anaerobic digestion
Fonte: Braz. j. microbiol;49(4):770-776, Oct.-Dec. 2018. tab, graf.
Idioma: en.
Projeto: Key Project of Education Department of Sichuan Province; . Major Cultivation Project of Education Department of Sichuan Province.
Resumo: ABSTRACT Anaerobic digestion is important for the management of livestock manure with high ammonia level. Although ammonia effects on anaerobic digestion have been comprehensively studied, the molecular mechanism underlying ammonia inhibition still remains elusive. In this study, based on metatranscriptomic analysis, the transcriptional profile of microbial community in anaerobic digestion under low (1500 mg L-1) and high NH4 + (5000 mg L-1) concentrations, respectively, were revealed. The results showed that high NH4 + concentrations significantly inhibited methane production but facilitated the accumulations of volatile fatty acids. The expression of methanogenic pathway was significantly inhibited by high NH4 + concentration but most of the other pathways were not significantly affected. Furthermore, the expressions of methanogenic genes which encode acetyl-CoA decarbonylase and methyl-coenzyme M reductase were significantly inhibited by high NH4 + concentration. The inhibition of the co-expressions of the genes which encode acetyl-CoA decarbonylase was observed. Some genes involved in the pathways of aminoacyl-tRNA biosynthesis and ribosome were highly expressed under high NH4 + concentration. Consequently, the ammonia inhibition on anaerobic digestion mainly focused on methanogenic process by suppressing the expressions of genes which encode acetyl-CoA decarbonylase and methyl-coenzyme M reductase. This study improved the accuracy and depth of understanding ammonia inhibition on anaerobic digestion.
Descritores: Bactérias/genética
Bactérias/metabolismo
Amônia/metabolismo
-Bactérias/isolamento & purificação
Bactérias/classificação
Transcrição Genética
Reatores Biológicos/microbiologia
Ácidos Graxos Voláteis/metabolismo
Microbiota
Anaerobiose
Metano/metabolismo
Responsável: BR1.1 - BIREME


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Id: lil-788957
Autor: Barros, Valciney Gomes de; Duda, Rose Maria; Oliveira, Roberto Alves de.
Título: Biomethane production from vinasse in upflow anaerobic sludge blanket reactors inoculated with granular sludge
Fonte: Braz. j. microbiol;47(3):628-639, July-Sept. 2016. tab, graf.
Idioma: en.
Projeto: CAPES; . CNPq.
Resumo: ABSTRACT The main objective of this study was to evaluate the anaerobic conversion of vinasse into biomethane with gradual increase in organic loading rate (OLR) in two upflow anaerobic sludge blanket (UASB) reactors, R1 and R2, with volumes of 40.5 and 21.5 L in the mesophilic temperature range. The UASB reactors were operated for 230 days with a hydraulic detection time (HDT) of 2.8 d (R1) and 2.8-1.8 d (R2). The OLR values applied in the reactors were 0.2-7.5 g totalCOD (L d)−1 in R1 and 0.2-11.5 g totalCOD (L d)−1 in R2. The average total chemical oxygen demand (totalCOD) removal efficiencies ranged from 49% to 82% and the average conversion efficiencies of the removed totalCOD into methane were 48-58% in R1 and 39-65% in R2. The effluent recirculation was used for an OLR above 6 g totalCOD (L d)−1 in R1 and 8 gtotalCOD (L d)−1 in R2 and was able to maintain the pH of the influent in R1 and R2 in the range from 6.5 to 6.8. However, this caused a decrease for 53-39% in the conversion efficiency of the removed totalCOD into methane in R2 because of the increase in the recalcitrant COD in the influent. The largest methane yield values were 0.181 and 0.185 (L) CH4 (gtotal COD removed)−1 in R1 and R2, respectively. These values were attained after 140 days of operation with an OLR of 5.0-7.5 g totalCOD (L d)−1 and total COD removal efficiencies around 70 and 80%.
Descritores: Esgotos/microbiologia
Fermentação
Metano/biossíntese
-Fósforo/metabolismo
Reatores Biológicos
Compostos Orgânicos Voláteis
Análise da Demanda Biológica de Oxigênio
Concentração de Íons de Hidrogênio
Anaerobiose
Nitrogênio/metabolismo
Responsável: BR1.1 - BIREME


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Id: biblio-1017978
Autor: Kita, Kiyishi; Takamiya, Shinzaburo; Furushima, Rieko; Villagra, Edgar; Wang, Hua; Aoki, Takashi; Oya, Hiroshi.
Título: Organización molecular del complejo II y su rol en la anaerobiosis. Revision / Molecular organization of complex II and its role in anaerobiosis. Review.
Fonte: Asunción; EFACIM; 1991. 136-144 p. tab.
Idioma: es.
Resumo: Complex II (Succinate-ubiquinone oxidoreductase) is an importnat enzyme complex for the tricarboxylic acid cycle and the aerobic respiratory chain of motochondria and procaryotic organisms (12, 24). Complex II catalyzes the oxidation of succinate to fumarate (Succinate dehydrogenase: sdh) and transfers its reducing equivalent to ubiquinone in the aerobic respiration
Descritores: Anaerobiose
Responsável: PY2.1 - Centro de Documentación
PY3.1 SR 616.9363 An78a 1991


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Id: biblio-1017975
Autor: Griffith, Fernando.
Título: Sistema celulolítico bacteriano: una vía hacia la sacrificación bilógica / The bacterial cellulolytic system: A way toward the biological saccharification.
Fonte: Asunción; EFACIM; 1991. 170-175 p.
Idioma: es.
Resumo: Studies on microbial degradation of cellulosic material have been performed over the past few years, and the enzymes involved in the biological saccharification of cellulose are subject of oncreasing interest because it constitutes the most abundant renewable carbon source on earth
Descritores: Anaerobiose
Clostridium
Responsável: PY2.1 - Centro de Documentación
PY3.1 SR 616.9363 An78a 1991


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Monteiro, Regina Teresa Rosim
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Id: biblio-839353
Autor: Dellamatrice, Priscila Maria; Silva-Stenico, Maria Estela; Moraes, Luiz Alberto Beraldo de; Fiore, Marli Fátima; Monteiro, Regina Teresa Rosim.
Título: Degradation of textile dyes by cyanobacteria
Fonte: Braz. j. microbiol;48(1):25-31, Jan.-Mar. 2017. tab, graf.
Idioma: en.
Resumo: Abstract Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black), and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds.
Descritores: Cianobactérias/metabolismo
Corantes/metabolismo
-Sementes/efeitos dos fármacos
Têxteis
Allium/efeitos dos fármacos
Brasil
Biotransformação
Alface/efeitos dos fármacos
Aerobiose
Corantes/toxicidade
Clorófitas/efeitos dos fármacos
Espectroscopia por Absorção de Raios X
Hydra/efeitos dos fármacos
Anaerobiose
Resíduos Industriais
Mutagênicos/metabolismo
Limites: Animais
Responsável: BR1.1 - BIREME


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Id: biblio-1050463
Autor: Fernández-Avelino, Lilith; García-Galicia, Arturo; Martínez-Hernández, Arturo Joel; Montiel-Jarquín, Alvaro José; Romero-Figueroa, María del Socorro; Blanco-Ochoa, Luis Carlos; López-Colombo, Aurelio; Meléndez-Mena, Daniel Erasmo; Amaro-Balderas, Eileen; Sánchez-Betanzos, Rafael; Loria-Castellanos, Jorge.
Título: Relación entre la saturación central venosa de oxígeno >_ 70% y la mortalidad en el choque séptico / Determination of the ratio of central venous oxygen saturation (ScvO2) > 70% mortality in septic shock. Patients admitted to pediatric intensive care unit
Fonte: Prensa méd. argent;104(8):391-402, oct2018. tab, fig.
Idioma: es.
Resumo: Objetivo: Determinar la Relación de la saturación central venosa de oxígeno (ScvO2) >_70% con la mortalidad, en el choque séptico en pacientes que ingresan al servicio de terapia intensiva pediátrica del HGR 36, Puebla. Métodos: Estudio, descriptivo, longitudinal, observacional. Se identificaron todos los pacientes de un mes a 14 años de edad que ingresaron a unidad de terapia intensiva con el diagnóstico de choque séptico. Se corroboró la colocación de un catéter venoso central para la medición de la ScvO2 a su ingreso y las 6 horas. Calificamos con el Indice Pediátrico de Mortalidad (PIM2) para medir el riesgo de mortalidad en cada paciente. Se realizó estadística descriptiva. Resultados: Fueron 15 pacientes, 8 (53.3%) femeninos y 7 (46.7%) masculinos. El PIM2 obtuvo un promedio de 7.42 % al ingreso, y a las 6 horas fue de 13.4%. El promedio de la saturación venosa central de oxígeno al ingreso de los pacientes a la terapia intensiva pediátrica fue de 56% y a las 6 horas el promedio alcanzó 71%. Ningún paciente falleció durante la reanimación cardiiopulmonar desde su ingreso. Conclusión: En base a los resultados anteriores podemos concluir, que no hay una correlación entre la ScvO2 >_ 70% y la mortalidad en los pacientes pediátricos con choque séptico

Objective: To determine the ratio of central venous oxygen saturation (ScvO2) >_ 70% mortality in septic shock patients admitted to pediatric intensive care unit of the HGR 36, Puebla. Methods: A descriptive, longitudinal, observational study. We identified all patients from one month to 14 years of age who were admitted to ICU with a diagnosis of septic shock. It confirmed the placement of a central venous atheter for the measurrement of income and ScvO2 to 6 hours. Qualified with the Pediatric Index of Mortality (PIM2) to measure the risk of death in each patient. We performed descriptive statistics. Results: there were 15 patients,eight (53.3%) female and 7 (46.7%) male. The PIM2 obtained an average of 7.42%. To entry, and 6 hours was 13.4%. The mean central venous oxygen saturation on admission of patients to the pediatric intensive care was 56% and 6 hours on average reached 71%. No patient died during cardiopulmonary resuscitation from your income. Conclusion: Based on previous results we can conclude that there is no coelation between ScvO2 >_70% and mortality in pediatric patients with septic shock
Descritores: Consumo de Oxigênio
Choque Séptico/mortalidade
Biomarcadores
Síndrome de Resposta Inflamatória Sistêmica/tratamento farmacológico
Sepse/mortalidade
Cuidados Críticos
Anaerobiose
Hipóxia/diagnóstico
Limites: Humanos
Recém-Nascido
Lactente
Pré-Escolar
Adolescente
Responsável: AR392.1 - Biblioteca


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Id: lil-555267
Autor: Bianchini Júnior, I; Silva, R. H; Cunha-Santino, M. B; Panhota, R. S.
Título: Aerobic and anaerobic decomposition of Pistia stratiotes leachates from a tropical eutrophic reservoir (Barra Bonita, SP, Brazil) / Decomposição aeróbia e anaerobia de lixiviados de Pistia stratiotes de um reservatório eutrófico tropical (Barra Bonita, SP, Brasil)
Fonte: Braz. j. biol;70(3):559-568, Aug. 2010. ilus, tab.
Idioma: en.
Projeto: CNPq.
Resumo: The present study discussed the kinetic aspects of leachate decomposition from an aquatic macrophyte, Pistia stratiotes L (water lettuce). This species was collected from Barra Bonita Reservoir located in the State of São Paulo (Brazil). Decomposition chambers were prepared with high molecular weight (HMW), low molecular weight (LMW) and integral (INT = HMW + LMW) dissolved organic matter (DOM) diluted with reservoir water. The samples were incubated at 20 °C, in darkness and under aerobic or anaerobic conditions. For 79 days, the concentrations of dissolved oxygen (DO) and organic carbon (OC) were measured. For calculating the deoxygenation coefficients (k d) and maximum oxygen consumption (COmax) the concentration of DO was integrated and fitted to a first-order kinetics model, which also applied to the depletion of OC concentrations. The COmax of INT incubations were 4 percent higher than the sum of HMW and LMW fractions. The deoxygenation coefficients, k d, had the same order of magnitude for all treatments. In relation to carbon decay, regardless of the availability of oxygen, the INT DOM also showed higher mineralisation. These results suggest that the leachate mineralisations are short-term processes; when the fractionation of the leachates occurs, the LMW had organic compounds with more accessibility for heterotrophic metabolism. On the other hand, when compared to INT DOM, the HMW and LMW were less consumed suggesting an interaction of the reactivity of the leachate. Our data suggest that in the Barra Bonita Reservoir the mineralisation of P. stratiotes leachates occurs through two competitive pathways (i.e. mineralisation of the labile compounds and formation of recalcitrant organic resources and their mineralisation) in which the oxygen availability and the molecular mass of DOM can interfere in the rates of reactions.

Nesse estudo foram discutidos aspectos cinéticos da decomposição de lixiviados da macrófita aquática Pistia stratiotes L (alface-d'água). A macrófita foi coletada no reservatório de Barra Bonita, localizado no Estado de São Paulo (Brasil). As câmaras de decomposição foram preparadas com amostras de água do reservatório e matéria orgânica dissolvida (MOD) de lixiviados com massa molecular alta (MMA), massa molecular baixa (MMB) e integral (INT = MMA + MMB). As amostras foram incubadas a 20 ºC, no escuro e sob condições aeróbias e anaeróbias. Durante 79 dias, as concentrações de oxigênio dissolvido (OD) e de carbono orgânico (CO) foram determinadas. Para os cálculos dos coeficientes de desoxigenação (k d) e das quantidades máximas de oxigênio consumido (OCmax), as concentrações de OD foram integradas e ajustadas a um modelo cinético de primeira ordem, que também foi empregado para os ajustes dos decréscimos das concentrações de CO. O OCmax da incubação com lixiviado integral (INT) foi 4 por cento maior que a soma dos OCmax das frações MMA e MMB. Os coeficientes de desoxigenação foram da mesma ordem de magnitude em todos os tratamentos. Em relação à perda de massa do carbono, independente da disponibilidade de oxigênio, a MOD INT apresentou as mineralizações mais elevadas. Os resultados sugeriram que as mineralizações desses lixiviados foram processos de curto prazo; na ocorrência de fracionamento, os lixiviados com MMB apresentam compostos orgânicos mais acessíveis aos metabolismos dos heterótrofos. Por outro lado, quando comparados com MOD INT, os lixiviados com MMB e MMA foram menos consumidos, sugerindo interação na reatividade dos lixiviados. Os resultados sugerem que no reservatório de Barra Bonita as mineralizações dos lixiviados de P. stratiotes ocorrem por duas rotas competitivas (i.e. mineralização dos compostos lábeis e formação de recursos refratários e sua mineralização), nas quais a disponibilidade de oxigênio e a massa molecular...
Descritores: Araceae/metabolismo
Biodegradação Ambiental
Carbono/metabolismo
Água Doce/química
Consumo de Oxigênio
-Aerobiose
Anaerobiose
Brasil
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


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Id: biblio-1017382
Autor: Mamimin, Chonticha; Prasertsan, Poonsuk; Kongjan, Prawit; O-Thong, Sompong.
Título: Effects of volatile fatty acids in biohydrogen effluent on biohythane production from palm oil mill effluent under thermophilic condition
Fonte: Electron. j. biotechnol;29:78-85, sept. 2017. tab, graf, ilus.
Idioma: en.
Projeto: Khon Kaen University; . Thailand Research Fund.
Resumo: Background: Biohydrogen effluent contains a high concentration of volatile fatty acid (VFA) mainly as butyric, acetic, lactic and propionic acids. The presence of various VFAs (mixture VFAs) and their cooperative effects on two-stage biohythane production need to be further studied. The effect of VFA concentrations in biohydrogen effluent of palm oil mill effluent (POME) on methane yield in methane stage of biohythane production was investigated. Results: The methane yield obtained in low VFA loading (0.9 and 1.8 g/L) was 15­20% times greater than that of high VFA loading (3.6 and 4.7 g/L). Butyric acid at high concentrations (8 g/L) has the individual significantly negative effect the methane production process (P b 0.05). Lactic, acetic and butyric acid mixed with propionic acid at a concentration higher than 0.5 g/L has an interaction significantly negative effect on the methanogenesis process (P b 0.05). Inhibition condition had a negative effect on both bacteria and archaea with inhibited on Geobacillus sp., Thermoanaerobacterium thermosaccharolyticum, Methanoculleus thermophilus and Methanothermobacter delfuvii resulting in low methane yield. Conclusion: Preventing the high concentration of butyric acid, and propionic acid in the hydrogenic effluent could enhance methane production in two-stage anaerobic digestion for biohythane production.
Descritores: Propionatos/metabolismo
Butiratos/metabolismo
Águas Residuárias/microbiologia
Metano/biossíntese
-Propionatos/análise
Butiratos/análise
Óleo de Palmeira
Methanobacteriaceae
Archaea
Methanomicrobiaceae
Geobacillus
Fermentação
Águas Residuárias/análise
Hidrogênio
Anaerobiose
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-889233
Autor: Qin, Wei; Fan, Fuqiang; Zhu, Yi; Huang, Xiaolong; Ding, Aizhong; Liu, Xiang; Dou, Junfeng.
Título: Anaerobic biodegradation of benzo(a)pyrene by a novel Cellulosimicrobium cellulans CWS2 isolated from polycyclic aromatic hydrocarbon-contaminated soil
Fonte: Braz. j. microbiol;49(2):258-268, Apr.-June 2018. graf.
Idioma: en.
Projeto: National Natural Science Foundation of China; . Fundamental Research Funds for the Central Universities.
Resumo: Abstract Cellulosimicrobium cellulans CWS2, a novel strain capable of utilizing benzo(a)pyrene (BaP) as the sole carbon and energy source under nitrate-reducing conditions, was isolated from PAH-contaminated soil. Temperature and pH significantly affected BaP biodegradation, and the strain exhibited enhanced biodegradation ability at temperatures above 30 °C and between pH 7 and 10. The highest BaP removal rate (78.8%) was observed in 13 days when the initial BaP concentration was 10 mg/L, and the strain degraded BaP at constant rate even at a higher concentration (50 mg/L). Metal exposure experimental results illustrated that Cd(II) was the only metal ion that significantly inhibited biodegradation of BaP. The addition of 0.5 and 1.0 g/L glucose enhanced BaP biodegradation, while the addition of low-molecular-weight organic acids with stronger acidity reduced BaP removal rates during co-metabolic biodegradation. The addition of phenanthrene and pyrene, which were degraded to some extent by the strain, showed no distinct effect on BaP biodegradation. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that the five rings of BaP opened, producing compounds with one to four rings which were more bioavailable. Thus, the strain exhibited strong BaP degradation capability and has great potential in the remediation of BaP-/PAH-contaminated environments.
Descritores: Microbiologia do Solo
Poluentes do Solo/metabolismo
Benzo(a)pireno/metabolismo
Actinobacteria/isolamento & purificação
Actinobacteria/metabolismo
-Temperatura
Cádmio/metabolismo
Carbono/metabolismo
Ácidos Carboxílicos/metabolismo
Biotransformação
Actinobacteria/classificação
Meios de Cultura/química
Inibidores Enzimáticos/metabolismo
Glucose/metabolismo
Concentração de Íons de Hidrogênio
Anaerobiose
Cromatografia Gasosa-Espectrometria de Massas
Responsável: BR1.1 - BIREME


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Id: biblio-1021550
Autor: Sharifyazd, Shabnam; Karimi, Keikhosro.
Título: Effects of fermentation conditions on valuable products of ethanolic fungus Mucor indicus
Fonte: Electron. j. biotechnol;30:77-82, nov. 2017. tab, graf.
Idioma: en.
Resumo: Background: Mucor indicus is a dimorphic fungus used in the production of ethanol, oil, protein, and glucosamine. It can ferment different pentoses and hexoses; however, the yields of products highly depend on the nutrients and cultivation conditions. In this study, the effects of different morphologic forms, cultivation time and temperature, presence or absence of oxygen, carbon sources, and concentration of nitrogen source on the products of M. indicus were investigated. Results: The fungus with all morphologies produced high yields of ethanol, in the range of 0.32­0.43 g/g, on glucose. However, the fungus with filamentous morphology produced higher amounts of oil, protein, phosphate, and glucosamine together with ethanol, compared with other morphologies. A higher amount of oil (0.145 g/g biomass) was produced at 28°C, while the best temperature for protein and glucosamine production was 32 and 37°C, respectively. Although ethanol was produced at a higher yield (0.44 g/g) under anaerobic conditions compared with aerobic conditions (yield of 0.41 g/g), aerobic cultivation resulted in higher yields of protein (0.51 g/g biomass), glucosamine (0.16 g/g alkali insoluble material, AIM), and phosphate (0.11 g/g AIM). Conclusions: It is not possible to have the maximum amounts of the products simultaneously. The fermentation conditions and composition of culture media determine the product yields. Carbon source type and the addition of nitrogen source are among the most influencing factors on the product yields. Moreover, all measured products were made with higher yields in cultivation on glucose, except glucosamine, which was produced with higher yields on xylose.
Descritores: Etanol/metabolismo
Mucor/metabolismo
-Temperatura
Fatores de Tempo
Óleos/metabolismo
Carbono/metabolismo
Biomassa
Aerobiose
Meios de Cultura
Fermentação
Glucosamina/metabolismo
Glucose
Anaerobiose
Nitrogênio/metabolismo
Responsável: CL1.1 - Biblioteca Central



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