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Id: biblio-843169
Autor: Alessandrello, Mauricio J; Vullo, Diana L.
Título: Medios de cultivo económicos para la producción de un biocatalizador a células enteras para el tratamiento de aguas residuales que contienen Cr(VI) / Economical fermentation media for the production of a whole cell catalyst for the treatment of Cr(VI)-containing wastewaters
Fonte: Rev. argent. microbiol;48(3):245-251, set. 2016. graf, tab.
Idioma: en.
Resumo: The biotechnology sector is continually seeking sustainable and more economical bioprocesses. Fermentation media produced with cheap components or wastes reduce production costs. Moreover, if wastes are used, they contribute to avoid environmental pollution. In this work, microbial growth media based on molasses or acidified glycerol as carbon sources and fertilizer as nitrogen source were tested for the production of a whole-cell catalyst that could be used in Cr(VI)-containing wastewater treatments. Results showed that the highest biomass production yield was obtained with a medium containing acidified glycerol 5% v/v and fertilizer 0.6% v/v. The biomass produced using this medium was immobilized in calcium alginate beads and used as catalyst in the biotransformation of Cr(VI) into Cr(III). The catalyst could be efficiently used for 5 reduction cycles of 40 mg/l Cr(VI) each. Cr(III) retention assays were performed to determine whether Cr(III) could be retained by the catalyst avoiding its solubilization in the supernatants. The retention capacity of the catalyst at 32 °C and pH 3.0 was 3 mg Cr(III)/g. Both an alternative and economical fermentation medium is here proposed for the optimization of Cr(VI)-containing wastewater treatment.

El sector industrial biotecnológico continuamente busca bioprocesos más económicos y sustentables. El uso de medios de cultivo producidos con componentes de bajo costo o con residuos reduce el presupuesto global del proceso y, particularmente si se utilizan residuos, se contribuye, además, a evitar la contaminación ambiental. En este trabajo se probaron medios de cultivo basados en melaza de caña o glicerol ácido como fuentes de carbono y energía, y fertilizante como fuente de nitrógeno, para la producción de un biocatalizador que podría ser usado para el tratamiento de aguas residuales que contienen Cr(VI). Los resultados mostraron que el mayor rendimiento de producción de biomasa se obtuvo con un medio que contenía 5% v/v de glicerol ácido y 0,6% v/v de fertilizante. Utilizando este medio se produjo la biomasa suficiente para la biotransformación de Cr(VI) a Cr(III), luego de ser inmovilizada en alginato de calcio. El proceso pudo ser aplicado eficientemente durante 5 ciclos de reducción de 40 mg/l de Cr(VI) cada uno. Además, se realizaron ensayos de retención de Cr(III) para determinar si esta especie química podría ser removida de la solución por interacción con el biocatalizador. La capacidad de retención obtenida por el biocatalizador a 32 °C y pH 3 fue de 3 mg de Cr(III)/g. De esta manera, se propone un medio de cultivo alternativo y económico para la efectivización de un tratamiento de aguas residuales que contengan Cr(VI).
Descritores: Biotransformação
Purificação da Água/métodos
Tecnologia de Baixo Custo/economia
Biocatálise
Águas Residuárias/microbiologia
-Cromo/análise
Purificação da Água/economia
Tipo de Publ: Estudo de Avaliação
Estudo de Validação
Estudo Observacional
Responsável: AR635.1 - FCVyS - Servicio de Información y Documentación


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Id: biblio-1254675
Autor: Huang, Jiafu; Huang, Axian; Lu, Luanmei; Jiang, Weikang; Zhang, Danfeng; Wu, Qici; Li, Peng; Zhong, Xiuyan.
Título: Improving the yield of Anoectochilus roxburghii by Bacillus licheniformis cultured in Agaricus bisporus industrial wastewater
Fonte: Electron. j. biotechnol;48:13-22, nov. 2020. tab, ilus, graf.
Idioma: en.
Projeto: Fujian Provincial Department of Science and Technology; . Fujian Provincial Department of Finance; . 2019 Fujian Provincial Science and Technology Commissioner Project; . Key Project of Fujian University Youth Natural Foundation; . Excellent Talents Project of Minnan Normal University of New Century; . Education Department of Fujian Province.
Resumo: BACKGROUND: There is a large amount of industrial wastewater produced by the mushroom industry during the canning processing each year, which could provide abundant carbon, nitrogen and inorganic salts for microbial growth. The aim of this study was to optimize the culture conditions for Bacillus licheniformis cultured in the Agaricus bisporus industrial wastewater to produce the agricultural microbial fertilizer. RESULTS: In this work, the maximal biomass of B. licheniformis could be obtained under the following culture conditions: 33.7°C, pH 7.0, 221 rpm shaking speed, 0.5% wastewater, 2 (v:v, %) inoculum dose, loading liquid of 60 mL/250 mL and a culture time of 24 h, and the average experimental value obtained was 1.35 ± 0.04 × 109 Obj/mL, which was within the 95% confidence interval of the predicted model (1.29­1.38 × 109 Obj/mL), and met the national microbial fertilizers' standard in China. Furthermore, the field experiment results showed that the fermentation broth of B. licheniformis could significantly improve the yield of Anoectochilus roxburghii. CONCLUSIONS: Agaricus bisporus industrial wastewater can be used to produce agricultural microbial fertilizer.
Descritores: Orchidaceae/fisiologia
Fertilizantes/microbiologia
Bacillus licheniformis/fisiologia
-Agaricus
Fermentação
Águas Residuárias
Citometria de Fluxo
Concentração de Íons de Hidrogênio
Resíduos Industriais
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1254671
Autor: Ibrahim, Salihu; Mohd Zahri, Khadijah Nabilah; Convey, Peter; Abdul Khalil, Khalilah; Gomez-Fuentes, Claudio; Zulkarnain, Azham; Alias, Siti Aisyah; González-Rocha, Gerardo; Ahmad, Siti Aqlima.
Título: Optimisation of biodegradation conditions for waste canola oil by cold-adapted Rhodococcus sp. AQ5-07 from Antarctica
Fonte: Electron. j. biotechnol;48:1-12, nov. 2020. tab, graf, ilus.
Idioma: en.
Projeto: PUTRA; . PUTRA-IPS; . PUTRA Berimpak.
Resumo: BACKGROUND: The potential waste canola oil-degrading ability of the cold-adapted Antarctic bacterial strain Rhodococcus sp. AQ5-07 was evaluated. Globally, increasing waste from food industries generates serious anthropogenic environmental risks that can threaten terrestrial and aquatic organisms and communities. The removal of oils such as canola oil from the environment and wastewater using biological approaches is desirable as the thermal process of oil degradation is expensive and ineffective. RESULTS: Rhodococcus sp. AQ5-07 was found to have high canola oil-degrading ability. Physico-cultural conditions influencing its activity were studied using one-factor-at-a-time (OFAT) and statistical optimisation approaches. Considerable degradation (78.60%) of 3% oil was achieved by this bacterium when incubated with 1.0 g/L ammonium sulphate, 0.3 g/L yeast extract, pH 7.5 and 10% inoculum at 10°C over a 72-h incubation period. Optimisation of the medium conditions using response surface methodology (RSM) resulted in a 9.01% increase in oil degradation (87.61%) when supplemented with 3.5% canola oil, 1.05 g/L ammonium sulphate, 0.28g/L yeast extract, pH 7.5 and 10% inoculum at 12.5°C over the same incubation period. The bacterium was able to tolerate an oil concentration of up to 4.0%, after which decreased bacterial growth and oil degradation were observed. CONCLUSIONS: These features make this strain worthy of examination for practical bioremediation of lipid-rich contaminated sites. This is the first report of any waste catering oil degradation by bacteria originating from Antarctica.
Descritores: Rhodococcus/fisiologia
Óleo de Brassica napus/metabolismo
-Resíduos
Biodegradação Ambiental
Adaptação Fisiológica
Temperatura Baixa
Águas Residuárias
Concentração de Íons de Hidrogênio
Regiões Antárticas
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1223226
Autor: Öztürk, Ayten; Bayol, Emel; Abdullah, Meysun I.
Título: Characterization of the biosorption of fast black azo dye K salt by the bacterium Rhodopseudomonas palustris 51ATA strain
Fonte: Electron. j. biotechnol;46:22-29, jul. 2020. tab, graf.
Idioma: en.
Projeto: Nigde Ömer Halisdemir University.
Resumo: BACKGROUND: Removal of dyes from wastewater by microorganisms through adsorption, degradation, or accumulation has been investigated. Biological methods used for dye treatment are generally always effective and environmentally friendly. In this study, biosorption of the Fast Black K salt azo dye by the bacterium Rhodopseudomonas palustris 51ATA was studied spectrophotometrically, at various pH (2­10), temperatures (25°C, 35°C, and 45°C) and dye concentrations (25­400 mg L-1). RESULTS: The bacterial strain showed extremely good dye-removing potential at various dye concentrations. IR studies at different temperatures showed that the dye was adsorbed on the bacterial surface at lower temperatures. Characteristics of the adsorption process were investigated by Scatchard analysis at 25°C and 35°C. Scatchard analysis of the equilibrium binding data for the dye on this bacterium gave rise to linear plots, indicating that the Langmuir model could be applied. The regression coefficients obtained for the dye from the Freundlich and Langmuir models were significant and divergence from the Scatchard plot was observed. CONCLUSION: The adsorption behavior of the dye on this bacterium was expressed by the Langmuir, Freundlich, and Temkin isotherms. The adsorption data with respect to various temperatures provided an excellent fit to the Freundlich isotherm. However, when the Langmuir and Temkin isotherm models were applied to these data, a good fit was only obtained for the dye at lower temperatures, thus indicating that the biosorption ability of R. palustris 51ATA is dependent on temperature, pH, and dye concentration.
Descritores: Rodopseudomonas/metabolismo
Compostos de Diazônio/metabolismo
Corantes/metabolismo
-Temperatura
Compostos Azo/análise
Compostos Azo/metabolismo
Remoção de Contaminantes
Adsorção
Corantes/análise
Águas Residuárias
Concentração de Íons de Hidrogênio
Responsável: CL1.1 - Biblioteca Central


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Id: lil-635698 LILACS-Express
Autor: RIVERA GONZÁLEZ, MASSIEL; GÓMEZ GÓMEZ, LILIANA.
Título: Identificación de cianobacterias potencialmente productoras de cianotoxinas en la curva de salguero del río cesar / Identificationoff cyanobacteria, potential cyaotoxins producers, in the cesarr river salguero's cuvee
Fonte: Rev. luna azul;(31):17-25, jul.-dic. 2010. ilus, tab.
Idioma: es.
Resumo: En el río Cesar, que se usa como receptor de aguas residuales tratadas de las lagunas de estabilización Estación Salguero, se llevó a cabo un plan de muestreo de 6 meses durante los cuales se identificaron cianobacterias potencialmente productoras de cianotoxinas, además se estimó cualitativamente su abundancia y variación en la distribución de éstas a lo largo del área de muestreo; se evaluaron las fluctuaciones de las características físicas y químicas del área de estudio. Se establecieron tres estaciones de muestreo: río arriba, zona de vertimiento de las aguas residuales y río abajo; se usaron métodos para la identificación y recuento del material ficológico estandarizados y para medir los parámetros físico-químicos. La mayor abundancia de algunas cianobacterias estuvo estrechamente relacionada con las zonas del río donde existe mayor contaminación orgánica. Las cianobacterias productoras de toxinas que predominaron fueron Phormidium sp., Oscillatoria sp. y Pseudanabaena sp. Los resultados fisicoquímicos indican que la calidad del agua del río Cesar es alterada en los puntos donde el río recibe las descargas de aguas residuales y a lo largo de éste.

A 6 month sampling plan was carried out in the Cesar River, which is used as the receiver of treated waste water from the stabilized ponds in Salguero Station. During this time cyanobacteria, potential producer of cyanotoxins, were identified, and also their abundance and variation in the distribution through the sampled area were estimated; fluctuations of physical and chemical characteristics of the area in study were evaluated. Three sample stations were established: upstream, the waste water flowing zone, and downstream. Standardized methods for the identification and recount of phycological material and to measure the physical-chemical parameters were used. The greater abundance of some cyanobacteria was closely related to the areas of the river where there is greater organic contamination. Cyanobacteria producers of toxins which were more predominant were Phormidium sp., Oscillatoria sp. and Pseudanabaena sp. The physical-chemical results indicate that the quality of the water in Cesar river is altered in the areas where the river receives the flow of waste warter and all along its steam.
Descritores: Águas Residuárias
-Qualidade da Água
Água
Cianobactérias
Limites: Humanos
Animais
Tipo de Publ: Artigo Clássico
Responsável: CO54.1 - Centro de Biblioteca e Información Científica


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Id: biblio-882840
Autor: Torres, Carlos; Echeverría, Silvia.
Título: Determinación preliminar de triclosán por espectroscopia UV-Vis en aguas residuales de la ciudad de Guatemala / Preliminary determination of triclosan by UV-Vis spectroscopy in wastewater from Guatemala city
Fonte: Cienc. tecnol. salud;4(1):79-86, 20170600. ilus.
Idioma: es.
Resumo: Estimar el grado de remoción de contaminantes emergentes en el proceso de tratamiento de aguas residuales es de importancia para evaluar la efectividad de las técnicas empleadas en la actualidad. El triclosán (TCS) es un agente antimicrobiano sintético de amplio espectro, estudios recientes sugieren que presenta elevado potencial como interruptor endocrino. Se determinó la concentración de TCS en cuatro muestras de aguas residuales obtenidas en diferentes etapas del proceso de tratamiento de aguas en la Planta Piloto para el Tratamiento de Aguas Residuales Ingeniero Arturo Pazos Sosa (IAPS). Las muestras de agua fueron filtradas en membrana, tratadas por adición de TCS estándar y formación de un compuesto complejo coloreado amarillo-café cuya absorbancia a 475 nm fue registrada en un espectrofotómetro Cary® 50 UV-Vis. Se identificó la presencia de TCS en concentraciones por arriba de 200 µg/L en tres diferentes etapas del tratamiento de aguas residuales en la planta piloto IAPS lo que permitió concluir que el grado de remoción de TCS en esta planta de tratamiento de aguas osciló entre 31 y 95% dependiendo de la etapa de tratamiento, sin embargo el agua del efluente de la planta no puede considerarse como potable ya que la concentración de TCS determinada en este estudio sobrepasa por al menos un orden de magnitud de diez los niveles a los cuales no se han reportado efectos adversos hacia organismos vivos.

Estimating the degree of contaminants' removal during wastewater treatment is important to evaluate the effectiveness of the current treatment techniques. Triclosan (TCS) is a synthetic broad spectrum antimicrobial agent and recent investigations suggest that this compound has high potential as endocrine disruptor. The concentration of TCS was measured in four wastewater samples obtained at different processing steps at the Ingeniero Arturo Pazos Sosa (IAPS) pilot plant. The wastewater samples were treated by membrane filtration, standard addition of TCS and the subsequent formation of a brown-yellow colored complex, whose absorbance at 475nm was measured in a Cary 50® UV-Vis spectrophotometer. TCS was found at concentrations over 200 µg/L in three different phases of the wastewater treatment at the IAPS plant. In conclusion, the degree of TCS removal in this plant was between 31 and 95% depending on the treatment stage. However plant effluent cannot be considered potable since the TCS concentration found in this study is at least ten times higher than those at which adverse effects to living organisms have not been detected.
Descritores: Triclosan/análise
Águas Residuárias/toxicidade
-Purificação da Água
Remoção de Contaminantes
Poluentes Ambientais/toxicidade
Disruptores Endócrinos/análise
Águas Residuárias
Limites: Humanos
Masculino
Feminino
Tipo de Publ: Relatos de Casos
Responsável: GT49.1


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Id: biblio-868834
Autor: Siguí, Norman L.
Título: ¿Por qué continúa la contaminación de aguas en Guatemala? / Why does water pollution continue in Guatemala?
Fonte: Cienc. tecnol. salud;3(2):167-175, jul.-dic. 2016.
Idioma: es.
Resumo: Para la protección ambiental se han emitido en Guatemala tres reglamentos que se refieren al agua residual, y una ley de protección y mejoramiento del medio ambiente. El último reglamento emitido es el Acuerdo Gubernativo 236-2006, denominado Reglamento de las Descargas y Reúso de Aguas Residuales y de la Disposiciónde Lodos, que derogó los reglamentos anteriores (Acuerdo Gubernativo del Reglamento de Requisitos Mínimos y sus Límites Máximos Permisibles de Contaminación para la Descarga de Aguas Servidas (1989) y Acuerdo Gubernativo del Reglamento de Descargas de Aguas Residuales a Cuerpos Receptores (2005)). El problema es que, el reglamento vigente tiene varias deficiencias y en muchos aspectos no mejoró lo que se había estipulado en losacuerdos previos, además al compararlo con los reglamentos equivalentes de México y Costa Rica, el reglamento guatemalteco es ineficaz. Entre las carencias se encuentra que; no diferencia los cuerpos de agua receptores, el plazo de cumplimiento es largo, no distingue tipos de industria, se redujeron las categorías de reúso de agua residual, disminuye el involucramiento del Ministerio de Salud Pública y Asistencia Social, la periodicidad de muestreoses menor, no se considera la medición de demanda química de oxígeno, la medición de color en el agua no es la adecuada y no considera la presencia de parásitos en las descargas. En virtud de la protección ambiental que el país requiere, es necesario realizar una revisión al Acuerdo Gubernativo de 2006 del Reglamento de las Descargas y Reúso de Aguas Residuales y de la Disposición de Lodos, que debería concluir con la derogación del reglamento y la emisión de uno nuevo más completo, mejorado y que se base en investigación científica.

For the environmental protection in Guatemala there have been three regulations for discharge and reuse of wastewater and sludge disposal, and one law for environmental protection. The last regulation issued that is currentlyin force is the Environment Agreement 236-2006 “Regulation of Discharge and Reuse of Wastewater and SludgeDisposal”, repealing the previous regulations (Government Agreement 60-1989 and 66-2005). But the regulation 236-2006 has many deficiencies and in many aspects did not improve what had been stipulated in the previous agreements, also when is compared with the regulations of Mexico and Costa Rica, Guatemala's regulations are ineffective. Among the deficiencies in 236-2006, it is observed that: there is not difference between receiving bodies,the compliance deadline is long, there is not difference for industries and their wastewater, the reuse categoriesfor wastewater was reduced, there is less engagement of the Health Ministry, less frequency of sampling, it is notconsidered the measurement of chemical oxygen demand, color measurement in water is not adequate and there isnot consideration for the presence of helminths in the treated wastewater. For the environmental protection that thecountry needs, it is necessary to perform a review of the Government Agreement 236-2006 and it should conclude with the repeal of regulation and issuance of a new one more complete, improved and based on scientific research.
Descritores: Águas Residuárias/legislação & jurisprudência
Parasitos
Política Ambiental
Limites: Humanos
Animais
Responsável: GT49.1


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Id: biblio-834322
Autor: Pérez-Sabino, Francisco; Valladares-Jovel, Balmore; Hernández, Elisandra; Oliva, Bessie; Del Cid, Marta; Jayes-Reyes, Pedro.
Título: Determinación de arsénico y mercurio en agua superficial del lago de Atitlán / Determination of arsenic and mercury levels in superfitial water of Atitlán lake
Fonte: Cienc. tecnol. salud;2(2):127-134, jul.-dic. 2015. ilus, tab.
Idioma: es.
Resumo: El lago de Atitlán, considerado uno de los lagos más bellos del mundo, tiene una superficie de 125.7 km2, una profundidad máxima de aproximadamente 350 m, y se encuentra en el departamento de Sololá, en el occidente de Guatemala. Desde 2009 se han observado floraciones extensivas de cianobacterias en el lago, reflejando la contaminación del agua en la cuenca. Se determinaron los niveles dearsénico (As) y mercurio (Hg) en agua superficial del lago de Atitlán, por espectrofotometría de absorción atómica (EAA), en cuatro muestreos realizados en marzo, mayo, agosto y octubre de 2014 en 14 sitios. Diez sitios se encuentran localizados en el lago, habiendo sido definidos en estudios anteriores con base en su cercanía a poblaciones asentadas en la orillas del lago. Dos sitios corresponden a los principales ríos tributarios, y los restantes dos sitios a la entrada y salida de la planta de tratamiento Los Cebollales, ubicada en Panajachel. Los niveles de As encontrados en el lago de Atitlán, tributarios y en la planta de tratamiento, fueron superiores a 20 μg/L. Los resultados indican que la contaminación del lago de Atitlán por As se debe principalmente a la geología de la cuenca, al localizarse en una zona volcánica. Los niveles cuantificables de As, son superiores al nivel máximo permitido para agua potable en la Norma de Agua Potable (NGO 29001:99) de la Comisión Guatemalteca de Normas (COGUANOR), por lo que el agua del lago de Atitlán no se considera apta para el consumo humano.

Lake Atitlan is considered one of the most beautiful lakes in the world. It has 125.7 km2 and 350 m maximum depth. It is located at the western province Sololá in the Guatemalan highlands. Since 2009 several cyanobacterial blooms have occurred at the lake, as consequence of the environmental degradation caused by water contamination into the basin. In this study pollution levels by arsenic (As) and mercury (Hg) in Lake Atitlan, were investigated in collaboration with the Authority for the Sustainable Management of Lake Atitlan and its Surroundings (AMSCLAE). Four samplings were conducted in March, May, August and October 2014, collecting samples of water at 14 sampling sites, including the Wastewater Treatment Plant located at Panajachel. As and Hg in water samples of Lake Atitlan were analyzed by atomic absorption spectrophotometry. Presence of arsenic above 20 μg/L was found in the water of Lake Atitlan, rivers and the wastewater treatment plant. The results indicate that contamination of Lake Atitlan regarding metals, is due majorly to the Basin geology located in a volcanic region. The levels of As are higher than recommended levels for drinking water in different regulations.
Descritores: Águas Residuárias
Espectrofotometria Atômica
Metais Pesados
Limites: Humanos
Masculino
Feminino
Responsável: GT49.1


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Texto completo SciELO Chile
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Id: biblio-950788
Autor: Chen, Peng; Wang, Yuxia; Yan, Lei; Wang, Yiqing; Li, Suyue; Yan, Xiaojuan; Wang, Ningbo; Liang, Ning; Li, Hongyu.
Título: Feasibility of biohydrogen production from industrial wastes using defined microbial co-culture
Fonte: Biol. Res;48:1-8, 2015. ilus, graf, tab.
Idioma: en.
Projeto: Gansu Province Science Foundation for Distinguished Young Scholars; . Longyuan Support Project for Young Creative Talents; . Technology Program of Gansu Province; . Technology Program of Lanzhou City; . NationalNaturalScience Foundation of China.
Resumo: BACKGROUND: The development of clean or novel alternative energy has become a global trend that will shape the future of energy. In the present study, 3 microbial strains with different oxygen requirements, including Clostridium acetobutylicum ATCC 824, Enterobacter cloacae ATCC 13047 and Kluyveromyces marxianus 15D, were used to construct a hydrogen production system that was composed of a mixed aerobic-facultative anaerobic-anaerobic consortium. The effects of metal ions, organic acids and carbohydrate substrates on this system were analyzed and compared using electrochemical and kinetic assays. It was then tested using small-scale experiments to evaluate its ability to convert starch in 5 L of organic wastewater into hydrogen. For the one-step biohydrogen production experiment, H1 medium (nutrient broth and potato dextrose broth) was mixed directly with GAM broth to generate H2 medium (H1 medium and GAM broth). Finally, Clostridium acetobutylicum ATCC 824, Enterobacter cloacae ATCC 13047 and Kluyveromyces marxianus 15D of three species microbial co-culture to produce hydrogen under anaerobic conditions. For the two-step biohydrogen production experiment, the H1 medium, after cultured the microbial strains Enterobacter cloacae ATCC 13047 and Kluyveromyces marxianus 15D, was centrifuged to remove the microbial cells and then mixed with GAM broth (H2 medium). Afterward, the bacterial strain Clostridium acetobutylicum ATCC 824 was inoculated into the H2 medium to produce hydrogen by anaerobic fermentation. RESULTS: The experimental results demonstrated that the optimum conditions for the small-scale fermentative hydrogen production system were at pH 7.0, 35°C, a mixed medium, including H1 medium and H2 medium with 0.50 mol/L ferrous chloride, 0.50 mol/L magnesium sulfate, 0.50 mol/L potassium chloride, 1% w/v citric acid, 5% w/v fructose and 5% w/v glucose. The overall hydrogen production efficiency in the shake flask fermentation group was 33.7 mL/h-1.L-1, and those the two-step and the one-step processes of the small-scale fermentative hydrogen production system were 41.2 mLVh-1.L-1 and 35.1 mL/h-1.L-1, respectively. CONCLUSION: Therefore, the results indicate that the hydrogen production efficiency of the two-step process is higher than that of the one-step process.
Descritores: Fermentação/fisiologia
Consórcios Microbianos/fisiologia
Hidrogênio/metabolismo
Resíduos Industriais
-Amido/metabolismo
Fatores de Tempo
Kluyveromyces/metabolismo
Ácidos Carboxílicos/metabolismo
Estudos de Viabilidade
Enterobacter cloacae/metabolismo
Técnicas de Cocultura
Clostridium acetobutylicum/metabolismo
Condutividade Elétrica
Interações Microbianas/fisiologia
Energia Renovável
Águas Residuárias/análise
Hidrogênio/análise
Íons/metabolismo
Metais/metabolismo
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: CL1.1 - Biblioteca Central


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Texto completo SciELO Brasil
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Id: biblio-1132185
Autor: Castro, Luiz Eduardo Nochi de; Meurer, Eduardo César; Alves, Helton José; Santos, Marco Aurélio Reis dos; Vasques, Erika de Castro; Colpini, Leda Maria Saragiotto.
Título: Photocatalytic Degradation of Textile dye Orange-122 Via Electrospray Mass Spectrometry
Fonte: Braz. arch. biol. technol;63:e20180573, 2020. tab, graf.
Idioma: en.
Resumo: Abstract This work reports the study of the potential application of Zn/TiO2 catalysts, obtained by the sol-gel method, in processes of environmental decontamination through the reactions of photodegradation of textile dye, followed by electrospray mass spectrometry. The catalysts synthesis was performed according to a 2² factorial design with repetition at the central point. The characterization techniques used were: N2 adsorption measurements (BET method), scanning electron microscopy with energy dispersive X-ray (MEV/EDS), X-ray diffraction and point of zero charge (PZC). The photocatalytic tests were performed in batch in the presence of sunlight, and to evaluate the degradation kinetics study, a rapid direct injection electrospray mass spectrometry (DI-ESI-MS) method has been developed. By the photocatalytic tests, the calcination temperature of 400 °C has shown the best results of discoloration for the reactive Orange-122 dye (99.76%) in a reaction time of 2h. The discoloration kinetics were a pseudo-first order, and a statistical analysis was performed to investigate the effects of the variables and to optimize the conditions of discoloration to the dye. After the reactional time of 2 h, an ion of m/z 441.5 was detected by ESI-MS, indicating that the photocatalytic process was effective for the degradation of the dye to secondary compounds.
Descritores: Compostos Azo/toxicidade
Biodegradação Ambiental
Descontaminação/métodos
Espectrometria de Massas em Tandem/métodos
Recuperação e Remediação Ambiental/métodos
Águas Residuárias
-Fotoquímica
Têxteis/toxicidade
Microscopia Eletrônica de Varredura
Catálise
Domínio Catalítico
Espectrometria de Massas por Ionização por Electrospray
Corantes
Fotobiorreatores
Modelos Teóricos
Responsável: BR1.1 - BIREME



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