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Pesquisa : D01.268.150 [Categoria DeCS]
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Id: biblio-1022610
Autor: Xiao, Qiong; Zhu, Yanbing; Li, Jiajia; Wu, Changzheng; Ni, Hui; Xiao, Anfeng.
Título: Fermentation optimization and enzyme characterization of a new ι-Carrageenase from Pseudoalteromonas carrageenovora ASY5
Fonte: Electron. j. biotechnol;32:26-34, Mar. 2018. graf, tab.
Idioma: en.
Projeto: University-Enterprise Cooperation of Fujian Province; . Public Science and Technology Research Funds Projects of Ocean; . Major Science and Technology Programs and Special Topics of Fujian Province; . Key Program of Science Foundation of Fujian Province.
Resumo: Background: A new ι-carrageenase-producing strain was screened from mangroves and authenticated as Pseudoalteromonas carrageenovora ASY5 in our laboratory. The potential application of this new strain was evaluated. Results: Medium compositions and culturing conditions in shaking flask fermentation were firstly optimized by single-factor experiment. ι-Carrageenase activity increased from 0.34 U/mL to 1.08 U/mL after test optimization. Optimal fermentation conditions were 20°C, pH 7.0, incubation time of 40 h, 15 g/L NaCl, 1.5% (w/v) yeast extract as nitrogen source, and 0.9% (w/v) ι-carrageenan as carbon source. Then, the crude ι-carrageenase was characterized. The optimum temperature and pH of the ι-carrageenase were 40°C and 8.0, respectively. The enzymatic activity at 35­40°C for 45 min retained more than 40% of the maximum activity. Meanwhile, The ι-carrageenase was inhibited by the addition of 1 mmol/L Cd2+ and Fe3+ but increased by the addition of 1 mmol/L Ag+, Ba2+, Ca2+, Co2+, Mn2+, Zn2+, Fe2+, and Al3+. The structure of oligosaccharides derived from ι-carrageenan was detected using electrospray ionization mass spectrometry (ESI-MS). The ι-carrageenase degraded ι-carrageenan, yielding disaccharides and tetrasaccharides as main products. Conclusions: The discovery and study of new ι-carrageenases are beneficial not only for the production of ι-carrageenan oligosaccharides but also for the further utilization in industrial production.
Descritores: Proteínas de Bactérias/metabolismo
Pseudoalteromonas/enzimologia
Glicosídeo Hidrolases/metabolismo
-Oligossacarídeos/biossíntese
Temperatura Ambiente
Carbono/metabolismo
Carragenina/biossíntese
Espectrometria de Massas por Ionização por Electrospray
Fermentação
Concentração de Íons de Hidrogênio
Hidrólise
Nitrogênio/metabolismo
Responsável: CL1.1 - Biblioteca Central


  2 / 182 LILACS  
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Id: biblio-1021560
Autor: Matsakas, Leonidas; Giannakou, Maria; Vörös, Dimitrij.
Título: Effect of synthetic and natural media on lipid production from Fusarium oxysporum
Fonte: Electron. j. biotechnol;30:95-102, nov. 2017. tab, graf.
Idioma: en.
Resumo: Background: Dependence on fossil resources, for the production of fuels and energy, has resulted in environmental and financial problems, which require our immediate action in order to reverse the situation. Use of renewable sources for the production of fuels and energy is an important alternative with biodiesel remains as one of the promising options. Aim of this work is to evaluate the fungus Fusarium oxysporum for its potentials to accumulate microbial lipids when grown on synthetic media and saccharified sweet sorghum stalks. Results: The effect of different carbon sources, nitrogen sources and C/N ratio on the lipid production was initially examined, which resulted in a lipid concentration of 4.4 g/L, with lipid content of 42.6% w/w. Sweet sorghum stalks were able to support growth and lipid production of the fungus, both as carbon source and as nitrogen source. It was also shown that saccharification of the dried stalks is an important step to increase lipid production. Removal of the remaining stalk solids enabled the lipid production during cultivation in increased initial solids of up to 16 w/w. This resulted in a lipid production of 3.81 g/L. Conclusions: It was demonstrated that F. oxysporum can be used as an efficient oleaginous microorganism, with sweet sorghum serving as an excellent raw material for the cultivation of the fungus. The lipids obtained during this work were also found to have a fatty acid profile with good potentials to be used for biodiesel production.
Descritores: Fusarium/metabolismo
Lipídeos/biossíntese
-Carbono/metabolismo
Biomassa
Recursos Renováveis
Combustíveis
Meios de Cultura
Ésteres
Metabolismo dos Lipídeos
Ácidos Graxos/análise
Biocombustíveis
Fermentação
Fusarium/química
Hidrólise
Lipídeos/análise
Nitrogênio/metabolismo
Responsável: CL1.1 - Biblioteca Central


  3 / 182 LILACS  
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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 Ambiente
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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Id: biblio-1016080
Autor: Oppermann, Tobias; Busse, Nadine; Czermak, Peter.
Título: Mannheimia haemolytica growth and leukotoxin production for vaccine manufacturing: a bioprocess review
Fonte: Electron. j. biotechnol;28:95-100, July. 2017. tab.
Idioma: en.
Resumo: Mannheimia haemolytica leukotoxin (LKT) is a known cause of bovine respiratory disease (BRD) which results in severe economic losses in the cattle industry (up to USD 1 billion per year in the USA). Vaccines based on LKT offer the most promising measure to contain BRD outbreaks and are already commercially available. However, insufficient LKT yields, predominantly reflecting a lack of knowledge about the LKT expression process, remain a significant engineering problem and further bioprocess optimization is required to increase process efficiency. Most previous investigations have focused on LKT activity and cell growth, but neither of these parameters defines reliable criteria for the improvement of LKT yields. In this article, we review the most important process conditions and operational parameters (temperature, pH, substrate concentration, dissolved oxygen level, medium composition and the presence of metabolites) from a bioprocess engineering perspective, in order to maximize LKT yields.
Descritores: Toxinas Bacterianas/biossíntese
Mannheimia haemolytica/metabolismo
Complexo Respiratório Bovino/microbiologia
Exotoxinas/biossíntese
-Temperatura Ambiente
Oligoelementos
Carbono/metabolismo
Mannheimia haemolytica/patogenicidade
Aminoácidos/metabolismo
Concentração de Íons de Hidrogênio
Cinetina
Limites: Animais
Bovinos
Tipo de Publ: Revisão
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1015999
Autor: Ahmadi, Negin; Khosravi-Darani, Kianoush; Mortazavian, Amir Mohammad.
Título: An overview of biotechnological production of propionic acid: from upstream to downstream processes
Fonte: Electron. j. biotechnol;28:67-75, July. 2017.
Idioma: en.
Resumo: The increasing demand for propionic acid (PA) production and its wide applications in several industries, especially the food industry (as a preservative and satiety inducer), have led to studies on the low-cost biosynthesis of this acid. This paper gives an overview of the biotechnological aspects of PA production and introduces Propionibacterium as the most popular organism for PA production. Moreover, all process variables influencing the production yield, different simple and complex carbon sources, the metabolic pathway of production, engineered mutants with increased productivity, and modified tolerance against high concentrations of acid have been described. Furthermore, possible methods of extraction and analysis of this organic acid, several applied bioreactors, and different culture systems and substrates are introduced. It can be concluded that maximum biomass and PA production may be achieved using metabolically engineered microorganisms and analyzing the most significant factors influencing yield. To date, the maximum reported yield for PA production is 0.973 g·g-1, obtained from Propionibacterium acidipropionici in a three-electrode amperometric culture system in medium containing 0.4 mM cobalt sepulchrate. In addition, the best promising substrate for PA bioproduction may be achieved using glycerol as a carbon source in an extractive continuous fermentation. Simultaneous production of PA and vitamin B12 is suggested, and finally, the limitations of and strategies for competitive microbial production with respect to chemical process from an economical point of view are proposed and presented. Finally, some future trends for bioproduction of PA are suggested.
Descritores: Propionatos/metabolismo
Propionibacterium/metabolismo
-Propionatos/química
Vitamina B 12/biossíntese
Carbono/metabolismo
Reatores Biológicos
Ácidos Graxos Voláteis/metabolismo
Fermentação
Concentração de Íons de Hidrogênio
Nitrogênio/metabolismo
Tipo de Publ: Revisão
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1010292
Autor: Heryani, Hesty; Putra, Meilana Dharma.
Título: Kinetic study and modeling of biosurfactant production using Bacillus sp
Fonte: Electron. j. biotechnol;27:49-54, May. 2017. graf, tab.
Idioma: en.
Resumo: Background: Surfactants are one of the most important raw materials used in various industrial fields as emulsifiers, corrosion inhibitors, foaming agents, detergent products, and so on. However, commercial surfactant production is costly, and its demand is steadily increasing. This study aimed to evaluate the performance of typical strains of Bacillus sp. to produce biosurfactants through fermentation. It also included the investigation of the effect of initial glucose concentration and the carbon to nitrogen ratio. Results: The biosurfactant yield was in the range of 1­2.46 g/L at initial glucose concentrations of 10­70 g/L. The optimum fermentation condition was achieved at a carbon to nitrogen ratio of 12.4, with a decrease in surface tension of up to 27 mN/m. Conclusions: For further development and industrial applications, the modified Gompertz equation is proposed to predict the cell mass and biosurfactant production as a goodness of fit was obtained with this model. The modified Gompertz equation was also extended to enable the excellent prediction of the surface tension.
Descritores: Tensoativos/metabolismo
Bacillus subtilis/metabolismo
-Tensoativos/química
Tensão Superficial
Bacillus subtilis/fisiologia
Carbono/análise
Cinética
Fermentação
Glucose/análise
Micelas
Nitrogênio/análise
Responsável: CL1.1 - Biblioteca Central


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Braile, Domingo M
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Id: lil-233888
Autor: Pinotti, Marcos; Garcia, Rogério M; Braile, Domingo M.
Título: Utilizaçäo de processamento digital de imagem para mediçäo do ângulo de contato formado entre soluçäo fisiológica e biomaterial / Use of digital image processing to measure the contact angle formed between physiologic and biomaterial solution
Fonte: In: Schiabel, Homero; Slaets, Annie France Frère; Costa, Luciano da Fontoura; Baffa Filho, Oswaldo; Marques, Paulo Mazzoncini de Azevedo. Anais do III Fórum Nacional de Ciência e Tecnologia em Saúde. Säo Carlos, s.n, 1996. p.600-600, ilus.
Idioma: pt.
Conferência: Apresentado em: Fórum Nacional de Ciência e Tecnologia em Saúde, 3 e Congresso Brasileiro de Engenharia Biomédica, 15 e Congresso Brasileiro de Físicos em Medicina , 6 e Congresso Brasileiro de Informática em Saúde, 5 e Encontro Brasileiro de Proteçäo Radiológica, Campos do Jordäo, 13-17 out. 1996.
Resumo: Processamento digital de imagem (PDI) foi empregado para a determinação do ângulo de contato formado entre solução fisiológica e uma superfície recoberta com carbono pirolítico. Os procedimentos experimentais e detalhes do processamento também são discutidos.
Descritores: Processamento de Sinais Assistido por Computador
Carbono
Equilíbrio Postural
Cloreto de Sódio
Materiais Biocompatíveis
-Substratos
Evaporação
Responsável: BR1.1 - BIREME
BR1.1/3012.80


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Id: lil-233849
Autor: Bastos, M. A. V; Vinagre Filho, U. M; Costa, V. L. da; Suita, J. C; Teixeira, D. L.
Título: Medida da funçäo de excitaçäo da reaçäo 65Cu(3He, 2n)66Ga / Measures of excitation function of the 65Cu(3He, 2n)66Ga reaction
Fonte: In: Schiabel, Homero; Slaets, Annie France Frère; Costa, Luciano da Fontoura; Baffa Filho, Oswaldo; Marques, Paulo Mazzoncini de Azevedo. Anais do III Fórum Nacional de Ciência e Tecnologia em Saúde. Säo Carlos, s.n, 1996. p.522-522, graf.
Idioma: pt.
Conferência: Apresentado em: Fórum Nacional de Ciência e Tecnologia em Saúde, 3 e Congresso Brasileiro de Engenharia Biomédica, 15 e Congresso Brasileiro de Físicos em Medicina , 6 e Congresso Brasileiro de Informática em Saúde, 5 e Encontro Brasileiro de Proteçäo Radiológica, Campos do Jordäo, 13-17 out. 1996.
Resumo: Foi medida a função excitação da reação (65)Cu(3He,2n)66Ga. Bombardeamentos de empilhamentos de duas folhas de Cu foram feitos a várias energias utilizando-se feixes de 3He de até 36 MeV do ciclotron CV-28 do IEN. A energia inicial do feixe de 3He foi medida por espectrometria de particulas carregadas com detectores Si(Au) posicionados a 90 graus Celsius com a direção do feixe incidente. As ativações das amostras foram medidas efetuando-se espectrometria de raios gama usando-se detectores de HPGe. A função excitação medida foi comparada com as encontradas na literatura.
Descritores: Espectrometria gama/estatística & dados numéricos
Ciclotrons/instrumentação
Cobre
Hélio
Isótopos
Radioisótopos de Gálio
-Brasil
Calibragem
Carbono
Fótons
Oxigênio
Responsável: BR1.1 - BIREME
BR1.1/3012.41


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Id: biblio-967308
Autor: Nunes, Luís Alfredo Pinheiro Leal; Pessoa, Maristella Calaço Moura; Silva, Francisco Rafael; Araújo, Ademir Sérgio Ferreira; Matos Filho, Carlos Humberto Aires; Santos, Valdinar Bezerra.
Título: Microbiological attributes of yellow oxissol under different monocultures in the savanna region of Piauí state / Atributos microbiológicos de um latossolos amarelo sob diferentes monoculturas no cerrado piauiense
Fonte: Biosci. j. (Online);34(5):1210-1218, sept./oct. 2018.
Idioma: en.
Resumo: Microbial biomass is an important component in maintaining soil quality and plant productivity. The aim of this paper was to evaluate alterations in microbiological attributes and organic carbon in accordance with seasonal change in different monocultures in the Savanna region of Piauí state. Soil samples were collected in areas of soy, eucalyptus, pasture, and in an area of native savanna, at depths of 0-0.20 m, during the rainy and dry periods. Using these samples microbial biomass carbon (MBC), basal respiration (BR), metabolic quotient (qCO2), microbial quotient (qMIC), and total organic carbon in the soil (TOC) were evaluated. MBC differed significantly between the systems evaluated, with higher values in the soil under native vegetation in the two sampling periods. TOC presented a significant difference between the systems, with higher values in the native savanna and soybean in the rainy period. For the qMIC, the soybean area presented lower values in the two periods compared with the other areas. Basal respiration as well as qCO2 values differed between the systems only in the dry period. The results reveal that the type of vegetation cover, management system, and seasonality influence the behavior of biological properties in the soil.

A biomassa microbiana é um componente importante para manter a qualidade do solo e a produtividade das plantas. O objetivo deste trabalho foi avaliar as alterações nos atributos microbiológicas e carbono orgânico, em função da variação sazonal em diferentes monoculturas no Cerrado piauiense. Amostras de solo foram coletadas em áreas de soja, eucalipto, pastagem e em uma área de mata nativa de Cerrado na profundidade de 0-0,20 m, durante o período chuvoso e seco. A partir dessas amostras avaliaram-se o carbono da biomassa microbiana (CBM), respiração basal (RB), quociente metabólico (qCO2), quociente microbiano (qMIC) e o carbono orgânico total do solo (COT). O CBM diferiu significativamente entre os sistemas avaliados, com maiores valores no solo sob mata nativa nos dois períodos de amostragem. O COT apresentou diferença significativa entre os sistemas, com maiores valores na mata nativa e soja no período chuvoso. Para o qMIC, a área com soja apresentou menores valores nos dois períodos em comparação às demais áreas. A RB assim como valores de qCO2 diferiram entre os sistemas apenas no período seco. Os resultados demonstram que o tipo de cobertura vegetal, o sistema de manejo e a sazonalidade influenciam o comportamento das propriedades biológicas do solo.
Descritores: Estações do Ano
Solo
Feijão de Soja
Carbono
Biomassa
Pradaria
Responsável: BR396.1 - Biblioteca Central


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Id: biblio-967306
Autor: Gomes, Romario Pimenta; Campos, Milton Cesar Costa; Brito, Wildson Benedito Mendes; Cunha, Jose Mauricio da; Muniz, Aleksander Westphal; Silva, Laercio Santos; Souza, Edicarlos Damacena de; Oliveira, Ivanildo Amorim; Freitas, Ludmila de.
Título: Variability and spatial correlation of aggregates and organic carbon in indian dark earth in Apuí region, AM / Variabilidade e correlação espacial de agregados e carbono orgânico em terra preta de índio na região do Apuí, AM
Fonte: Biosci. j. (Online);34(5):1188-1199, sept./oct. 2018.
Idioma: en.
Resumo: Having in mind the importance of knowing the variability and spatial correlation of soil properties in Indian Dark Earth (IDE), we evaluated in this study the variability and the spatial correlation of aggregates and carbon in an Ultisol under coffee cultivation in southern Amazonas. It was established a 48 x 88 m sampling grid spaced 06 x 08 m, totalling 88 sampling points. Then soil samples were collected at: 0.0-.05, 0.05-0.10, and 0.10-0.20 m layers. The spatial variability of the Mean Weighted Diameter (MWD) attributes, aggregates > 2 mm, < 2 mm, bulk density (BD) and organic carbon (OC) was analyzed by adjusting the simple semivariograms, while spatial correlations of the OC with aggregates and BD were analyzed by cross-semivariogram. We could conclude that there was spatial dependence in the variables, wherein the largest ones were observed at 0.0-0.05 m, except for Mean Weighted Diameter (MWD) and aggregates greater than 2.00 mm with larger range of values in depth from 0.05-0.10 and 0.10-0.20 m. The mean weight diameter and aggregate class attributes greater than 2.00 mm had negative spatial correlation with organic carbon at 0.0-0.05 m, while the smaller aggregates than 2.00 mm classes and bulk density correlated positively with organic carbon at 0.0-0.05 m and 0.10-0.20 m.

Considerando a importância do conhecimento da variabilidade e correlação espacial dos atributos do solo em Terra Preta de Índio (TPIs), avaliou-se neste trabalho a variabilidade e a correlação espacial de agregados e carbono em um Argissolo Amarelo eutrófico sob cultivo de café na região sul do Amazonas. Foi estabelecido um grid amostral com dimensões de 48 x 88 m e espaçamentos de 06 x 08 m, totalizando 88 pontos amostrais. Em seguida, foram coletadas amostras de solos nas profundidades: 0,0-0,05, 0,05-0,10, e 0,10-0,20 m. A variabilidade espacial dos atributos diâmetro médio ponderado (DMP), agregados > 2 mm, < 2 mm, densidade do solo (Ds) e carbono orgânico (CO) foi analisada ajustando os semivariogramas simples, enquanto as correlações espaciais do CO com agregados e Ds foram analisadas por semivariogramas cruzados. Concluiu-se que as variáveis apresentaram dependência espacial, e os maiores alcances são constatados na profundidade 0,0-0,05 m, exceto para DMP e agregados maiores que 2,00 mm com maiores valores de alcance na profundidade 0,05-0,10 e 0,10-0,20 m. Os atributos diâmetro médio ponderado e classes de agregados maior que 2,00 mm apresentam correlação espacial negativa com carbono orgânico na profundidade 0,0-0,05 m, enquanto a classes de agregados menor que 2,00 mm e densidade do solo apresentam correlação positiva com carbono orgânico nas profundidades 0,0-0,05 m e 0,10-0,20 m.
Descritores: Solo
Carbono
Café
Responsável: BR396.1 - Biblioteca Central



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