Base de dados : LILACS
Pesquisa : E07.115 [Categoria DeCS]
Referências encontradas : 98 [refinar]
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  1 / 98 LILACS  
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Texto completo SciELO Brasil
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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


  2 / 98 LILACS  
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Ayub, Marco Antonio Zachia
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Id: biblio-828200
Autor: Coghetto, Chaline Caren; Vasconcelos, Carolina Bettker; Brinques, Graziela Brusch; Ayub, Marco Antônio Záchia.
Título: Lactobacillus plantarum BL011 cultivation in industrial isolated soybean protein acid residue
Fonte: Braz. j. microbiol;47(4):941-948, Oct.-Dec. 2016. tab, graf.
Idioma: en.
Resumo: Abstract In this study, physiological aspects of Lactobacillus plantarum BL011 growing in a new, all-animal free medium in bioreactors were evaluated aiming at the production of this important lactic acid bacterium. Cultivations were performed in submerged batch bioreactors using the Plackett-Burman methodology to evaluate the influence of temperature, aeration rate and stirring speed as well as the concentrations of liquid acid protein residue of soybean, soy peptone, corn steep liquor, and raw yeast extract. The results showed that all variables, except for corn steep liquor, significantly influenced biomass production. The best condition was applied to bioreactor cultures, which produced a maximal biomass of 17.87 g L-1, whereas lactic acid, the most important lactic acid bacteria metabolite, peaked at 37.59 g L-1, corresponding to a productivity of 1.46 g L-1 h-1. This is the first report on the use of liquid acid protein residue of soybean medium for L. plantarum growth. These results support the industrial use of this system as an alternative to produce probiotics without animal-derived ingredients to obtain high biomass concentrations in batch bioreactors.
Descritores: Proteínas de Soja
Meios de Cultura
Lactobacillus plantarum/crescimento & desenvolvimento
Lactobacillus plantarum/metabolismo
-Biomassa
Ácido Láctico/biossíntese
Proteínas de Soja/metabolismo
Proteínas de Soja/química
Reatores Biológicos
Meios de Cultura/química
Metabolismo dos Carboidratos
Fermentação
Hidrólise
Responsável: BR1.1 - BIREME


  3 / 98 LILACS  
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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


  4 / 98 LILACS  
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Id: biblio-839351
Autor: An, Chao; Ma, Sai-jian; Chang, Fan; Xue, Wen-jiao.
Título: Efficient production of pullulan by Aureobasidium pullulans grown on mixtures of potato starch hydrolysate and sucrose
Fonte: Braz. j. microbiol;48(1):180-185, Jan.-Mar. 2017. tab, graf.
Idioma: en.
Projeto: Scientific and Technologic Research Program of Shaanxi Academy of Sciences, China; . WesternChinese Academy of Sciences; . Natural Science Basic Research Plan in Shaanxi Province of China; . Shaanxi Science & Technology Co-ordination & Innovation Project; . Science and Technology Program of Xi’an.
Resumo: Abstract Pullulan is a natural exopolysaccharide with many useful characteristics. However, pullulan is more costly than other exopolysaccharides, which limits its effective application. The purpose of this study was to adopt a novel mixed-sugar strategy for maximizing pullulan production, mainly using potato starch hydrolysate as a low-cost substrate for liquid-state fermentation by Aureobasidium pullulans. Based on fermentation kinetics evaluation of pullulan production by A. pullulans 201253, the pullulan production rate of A. pullulans with mixtures of potato starch hydrolysate and sucrose (potato starch hydrolysate:sucrose = 80:20) was 0.212 h−1, which was significantly higher than those of potato starch hydrolysate alone (0.146 h−1) and mixtures of potato starch hydrolysate, glucose, and fructose (potato starch hydrolysate:glucose:fructose = 80:10:10, 0.166 h−1) with 100 g L−1 total carbon source. The results suggest that mixtures of potato starch hydrolysate and sucrose could promote pullulan synthesis and possibly that a small amount of sucrose stimulated the enzyme responsible for pullulan synthesis and promoted effective potato starch hydrolysate conversion effectively. Thus, mixed sugars in potato starch hydrolysate and sucrose fermentation might be a promising alternative for the economical production of pullulan.
Descritores: Ascomicetos/metabolismo
Amido/metabolismo
Sacarose/metabolismo
Solanum tuberosum/química
Fermentação
Glucanos/biossíntese
-Amido/química
Carbono/metabolismo
Cinética
Biomassa
Reatores Biológicos
Técnicas de Cultura Celular por Lotes
Responsável: BR1.1 - BIREME


  5 / 98 LILACS  
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Texto completo SciELO Chile
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Id: lil-504112
Autor: Shohael, Abdullah Mohammad; Murthy, Hosakatte Niranjana; Hahn, Eun-Joo; Paek, Kee-Yoeup.
Título: Methyl jasmonate induced overproduction of eleutherosides in somatic embryos of Eleutherococcus senticosus cultured in bioreactors
Fonte: Electron. j. biotechnol;10(4):633-637, oct. 2007. tab.
Idioma: en.
Projeto: Ministry of Education and Human Resources Development; . Ministry of Commerce, Industry and Energy; . Ministry of Labor; . Korean Federation of Science and Technology Societies. Brain Pool Fellowship.
Resumo: This study was concentrated on the production of eleutherosides and chlorogenic acid in embryogenic suspension cultures of Eleutherococcus senticosus by exposing them to different concentrations (50-400 µM) of methyl jasmonate (MJ) during the culture period. In the bioreactor cultures, eleutheroside content increased significantly by elicitation of MJ, however, the fresh weight, dry weight and growth ratio of embryos was strongly inhibited by increasing MJ concentrations. The highest total eleutheroside (7.3 fold increment) and chlorogenic acid (3.9 fold increment) yield was obtained with 200 µM MJ treatment. There was 1.4, 3.4 and 14.9 fold increase in the eleutheroside B, E, and E1 production respectively with such elicitation treatment. These results suggest that MJ elicitation is beneficial for eleutheroside accumulation in the embryogenic cell suspension cultures.
Descritores: Eleutherococcus/metabolismo
Extratos Vegetais/análise
Reatores Biológicos
Reguladores de Crescimento de Planta/metabolismo
-Eleutherococcus/citologia
Eleutherococcus/embriologia
Membrana Celular/metabolismo
Técnicas de Cultura de Células
Responsável: CL1.1 - Biblioteca Central


  6 / 98 LILACS  
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Id: biblio-1021543
Autor: Panyachanakul, Titiporn; Kitpreechavanich, Vichien; Tokuyama, Shinji; Krajangsang, Sukhumaporn.
Título: Poly(DL-lactide)-degrading enzyme production by immobilized Actinomadura keratinilytica strain T16-1 in a 5-L fermenter under various fermentation processes
Fonte: Electron. j. biotechnol;30:71-76, nov. 2017. graf, ilus, tab.
Idioma: en.
Projeto: National Research Council of Thailand.
Resumo: Background: Poly(DL-lactic acid), or PDLLA, is a biodegradable polymer that can be hydrolyzed by various types of enzymes. The protease produced by Actinomadura keratinilytica strain T16-1 was previously reported to have PDLLA depolymerase activity. However, few studies have reported on PDLLA-degrading enzyme production by bacteria. Therefore, the aims of this study were to determine a suitable immobilization material for PDLLA-degrading enzyme production and optimize PDLLA-degrading enzyme production by using immobilized A. keratinilytica strain T16-1 under various fermentation process conditions in a stirrer fermenter. Results: Among the tested immobilization materials, a scrub pad was the best immobilizer, giving an enzyme activity of 30.03 U/mL in a shake-flask scale. The maximum enzyme activity was obtained at aeration 0.25 vvm, agitation 170 rpm, 45°C, and 48 h of cultivation time. Under these conditions, a PDLLA-degrading enzyme production of 766.33 U/mL with 15.97 U/mL·h productivity was observed using batch fermentation in a 5-L stirrer fermenter. Increased enzyme activity and productivity were observed in repeated-batch (942.67 U/mL and 19.64 U/mL·h) and continuous fermentation (796.43 U/mL and 16.58 U/mL·h) at a dilution rate of 0.013/h. Scaled-up production of the enzyme in a 10-L stirrer bioreactor using the optimized conditions showed a maximum enzyme activity of 578.67 U/mL and a productivity of 12.06 U/mL·h. Conclusions: This research successfully scaled-up the enzyme production to 5 and 10 L in a stirrer fermenter and is helpful for many applications of poly(lactic acid).
Descritores: Poliésteres/metabolismo
Actinomycetales/enzimologia
Enzimas/biossíntese
-Biodegradação Ambiental
Reatores Biológicos
Enzimas/metabolismo
Enzimas Imobilizadas
Fermentação
Responsável: CL1.1 - Biblioteca Central


  7 / 98 LILACS  
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Id: biblio-1009753
Autor: Song, Xiaolin; Wu, Hao; Piao, Xuanchun; Yin, Zhenhao; Yin, Chengri.
Título: Microbial transformation of ginsenosides extracted from Panax ginseng adventitious roots in an airlift bioreactor
Fonte: Electron. j. biotechnol;26:20-26, Mar. 2017. ilus, graf, tab.
Idioma: en.
Projeto: National Natural Science Foundation of China; . Natural Science Foundation of Jilin Province of China.
Resumo: Background: Ginsenoside is the most important secondary metabolite in ginseng. Natural sources of wild ginseng have been overexploited. Although root culture can reduce the length of the growth cycle of ginseng, the number of species of ginsenosides is reduced and their contents are lower in the adventitious roots of ginseng than in the roots of ginseng cultivated in the field. Results: In this study, 147 strains of ß-glucosidase-producing microorganisms were isolated from soil. Of these, strain K35 showed excellent activity for converting major ginsenosides into rare ginsenosides, and a NCBI BLAST of its 16S rDNA gene sequence showed that it was most closely related to Penicillium sp. (HQ608083.1). Strain K35 was used to ferment the adventitious root extract, and the fermentation products were analyzed by high-performance liquid chromatography. The results showed that the content of the rare ginsenoside CK was 0.253 mg mL-1 under the optimal converting conditions of 9 d of fermentation at pH 7.0 in LL medium, which was significantly higher than that in the adventitious roots of ginseng. Conclusion: These findings may not only solve the problem of low productivity of metabolite in ginseng root culture but may also result in the development of a new valuable method of manufacturing ginsenoside CK.
Descritores: beta-Glucosidase/metabolismo
Raízes de Plantas/metabolismo
Ginsenosídeos/metabolismo
Panax/metabolismo
-Penicillium
Biotransformação
Cromatografia Líquida de Alta Pressão
Raízes de Plantas/química
Reatores Biológicos
Ginsenosídeos/isolamento & purificação
Fermentação
Panax/crescimento & desenvolvimento
Panax/química
Responsável: CL1.1 - Biblioteca Central


  8 / 98 LILACS  
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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


  9 / 98 LILACS  
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Id: biblio-1008418
Autor: Martínez, Duniesky; Menéndez, Carmen; Hernández, Lázaro; Sobrino, Alina; Trujillo, Luis E; Rodríguez, Ivan; Pérez, Enrique R.
Título: Scaling-up batch conditions for efficient sucrose hydrolysis catalyzed by an immobilized recombinant Pichia pastoris cells in a stirrer tank reactor
Fonte: Electron. j. biotechnol;25:39-42, ene. 2017. tab, graf.
Idioma: en.
Resumo: Background: Invert sugar is used greatly in food and pharmaceutical industries. This paper describes scaling-up batch conditions for sucrose inversion catalyzed by the recombinant Pichia pastoris BfrA4X whole cells expressing Thermotoga maritima invertase entrapped in calcium alginate beads. For the first time, we describe the application of a kinetic model to predict the fractional conversion expected during sucrose hydrolysis reaction in both, a model and a prototype bioreactor with 0.5- and 5-L working volume, respectively. Results: Different scaled-up criteria used to operate the 0.5-L bioreactor were analyzed to explore the invert sugar large scale production. After model inversion studies, a 5-L scaled-up reaction system was performed in a 7-L stirred reactor. Both scaled-up criteria, immobilized biocatalyst dosage and stirring speed, were analyzed in each type of bioreactors and the collected data were used to ensure an efficient scale-up of this biocatalyst. Conclusions: To date, there is not enough information to describe the large-scale production of invert sugar using different scaled-up criteria such as dose of immobilized biocatalyst and stirring speed effect on mass transfer. The present study results constitute a valuable tool to successfully carry out this type of high-scale operation for industrial purposes.
Descritores: Pichia/metabolismo
Sacarose/metabolismo
Biotecnologia/métodos
-Pichia/citologia
Sacarose/química
Cinética
Reatores Biológicos
Thermotoga maritima/enzimologia
Alginatos
Enzimas Imobilizadas
Biocatálise
Hidrólise
Responsável: CL1.1 - Biblioteca Central


  10 / 98 LILACS  
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Id: biblio-911862
Autor: Martini, Cristina; Verruma-Bernardi, Marta Regina; Borges, Maria Teresa Mendes Ribeiro; Margarido, Luiz Antonio Correa; Ceccato-Antonini, Sandra Regina.
Título: Yeast composition of sugar cane juice in relation to plant varieties and seasonality / Composição de leveduras do caldo em relação às variedades de cana e sazonalidade
Fonte: Biosci. j. (Online);27(5):710-717, sept./oct. 2011. tab, graf.
Idioma: en.
Resumo: In the production of the artisanal cachaça, a beverage obtained after distillation of the fermented sugar cane juice, natural starter ferment ("fermento caipira") is utilized, in which crushed corn, rice bran and citric fruit juice are added to sugar cane juice. The primary microbial source is the juice itself, and although the cachaça sensorial quality is recognized when this ferment is utilized, difficulties in the quality control due to the high level of contaminants and extensive preparation periods are reported. In this context, this work aimed the evaluation of the yeast composition and physico-chemical characteristics of the juice extracted from 10 sugar cane RB-varieties during the harvest season in an area under organic management, seeking for information to contribute to the varietal management allowing a faster and efficient ferment preparation. A significant decrease in the yeast numbers in the juice was observed when the maximal point of maturity was reached for the majority of the varieties. However, the proportion (%) of Saccharomyces increased with the cane maturity, recommending the early and medium maturity varieties (RB835054, RB835486, RB845210 and RB855156) to be utilized at the beginning of the harvest period for the ferment preparation, which could result in diminished preparation time and faster fermentation. The variety RB845210 is indicated because it also presented high reducing sugar and protein concentrations in the juice. The varietal management can facilitate the production and performance of the natural starter ferment, in order to contribute for the organic cachaça production.

Na produção artesanal de cachaça, bebida obtida através da destilação do caldo de cana-de-açúcar fermentado, tradicionalmente utiliza-se o fermento natural ou também chamado de caipira, resultado da mistura de vários ingredientes como milho moído, farelo de arroz e suco de frutas cítricas com caldo de cana. A fonte primária de microrganismos é o próprio caldo da cana, e embora se reconheça a qualidade sensorial da bebida quando este tipo de fermento é utilizado, há alguns inconvenientes como dificuldades no controle de qualidade devido ao alto nível de contaminantes e longos períodos de preparação. Neste contexto, o objetivo deste trabalho foi avaliar a composição de leveduras e as características físico-químicas do caldo em relação às variedades de cana orgânica (10 variedades RB) e à sazonalidade, no intuito de gerar informações para o manejo de variedades que permita o preparo do fermento caipira de forma mais eficiente e rápida. Os resultados indicaram uma diminuição significativa no número de leveduras próximo ao ponto máximo de maturação da cana-de-açúcar para a maioria das variedades. Porém, observou-se que a proporção (%) de Saccharomyces aumentou em decorrência da maturação da cana. Sugere-se as variedades precoces e precoces/médias (RB835054, RB835486, RB845210 e RB855156) a serem utilizadas no início da safra para o preparo do fermento caipira, o que poderia proporcionar uma diminuição no tempo de preparo do fermento e uma fermentação mais rápida. A variedade RB845210 é indicada por apresentar também maior concentração de açúcar redutor e proteína no caldo. O manejo varietal pode facilitar a produção e eficiência do fermento caipira, contribuindo assim para a produção de cachaça orgânica.
Descritores: Bebidas Alcoólicas
Reatores Biológicos
Destilação
Fermentação
Saccharomyces
Leveduras
Responsável: BR396.4



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