Base de dados : LILACS
Pesquisa : E07.115 [Categoria DeCS]
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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


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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


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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


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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-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


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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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Id: biblio-905963
Autor: Moguel, Ignacio Sánchez.
Título: Production of L-asparaginase of pharmaceutical nterest from yeasts isolated from the Antarctic continent / Produção de L-asparaginase de interesse farmacêutico a partir de leveduras isoladas do continente Antártico.
Fonte: São Paulo; s.n; 2018. 120 p. tab, graf, ilus.
Idioma: en.
Tese: Apresentada a Universidade de São Paulo. Faculdade de Ciências Farmacêuticas para obtenção do grau de Doutor.
Resumo: The L-asparaginase (ASNase) obtained from yeasts species has been poorly studied and a new yeast ASNase could be an alternative to minimize the side effect in the treatment of lymphoblastic leukemia. The Antarctic ecosystems have a great potential to obtain novel enzymes produced from psychrophilic and psychrotolerant microorganisms. Yeasts isolated from samples collected in the Antarctic Peninsula by the PROANTAR expedition team were tested for the production of ASNase and L-glutaminase (GLNase). From this screening, the strain Leucosporidium scottii L115 presented the highest ASNase activity (6.24 U g-1 of dried cell weight (dcw)) with a combination of low GLNase activity (0.41 U g-1 dcw). The ASNase belonging to L. scottii L115 (LsASNase) was purified 227 fold with a specific activity of 137.01 U mg-1 at 37 ºC, and with 0.93 U mg-1 for GLNase. Moreover, the maximum activity was observed at pH 7.5 at 55 ºC. The enzyme is a multimer presenting a single band of 54.5 kDa of molecular weight in reduced conditions and 462 kDa by size exclusion chromatography. The LsASNase is a glycosylated enzyme that presented a band lower at 25 kDa when was treated with PGNase F. The enzymatic kinetic reveals an allosteric regulation of the enzyme and the kinetic parameters were determined at 37º C, pH 7.0 as K0.5 = 233 µM, kcat = 54.7 s-1 and nH = 1.52 demonstrating a positive cooperativity by the enzyme and the substrate. The ASNase production by L. scottii L115 was improved by applying DoE for the culture medium development. The PB and CDD designs were used to optimize the ASNase production providing the nutrient values of 6.15 g L-1 of proline, 28.34 g L-1 sucrose, and 15.61 g L-1 of glycerol for a maximal production. The synthetic medium containing the optimized quantities was added with the salts: KCl, 0.52 g L-1; MgSO4.7H2O, 0.52 g L-1; CuNO3.3H2O, 0.001 g L-1; ZnSO4.7H2O, 0.001 g L-1; FeSO4.7H2O, 0.001 g L-1.The optimized medium produces a 23.75 ULh-1 of ASNase in shake flask culture. Furthermore, L. scottii is characterized as an oleaginous yeast that accumulates lipids with a suitable fatty acid profile. The production of ASNase and lipids were scaled up in the 1 L bioreactor to evaluate the initial cell concentration, carbon source, and oxygen transfer rate (kLa).The experiments were performed at 15ºC in the bioreactor BIOSTAT®Q plus (Sartorius Stedim, Germany) in batch mode, using 0.5 L of the optimized medium culture in phosphate buffer 50 mM pH 7.0. The initial cell concentration was evaluated at 1%, 3%, and 5% (v/v). Sucrose and glycerol were tested alone to examine if the combination of both is mandatory to produce ASNase. All these assays were carried in duplicate. The kLa was assessed through a CCD design in the range of 1.42 - 123.0 h-1. The performance in bioreactor showed the productivity of 36.95 ULh-1of ASNase under the optimized conditions (growth temperature 15º C, X0: 5 g L-1, pH 7.0, 48 h, kLa 89-92 h-1). The cultivation of L. scottii L115 at 15ºC in sucrose and glycerol as carbon sources generate an interesting lipid profile, where it presents monounsaturated and polyunsaturated lipids

A L-asparaginase (ASNase) obtida a partir de espécies de leveduras tem sido pouco estudada e uma nova ASNase de levedura pode ser uma alternativa para minimizar os efeitos adversos no tratamento da leucemia linfoblástica. Os ecossistemas Antárticos têm um grande potencial para obter novas enzimas produzidas a partir de microorganismos psicrofílicos e psicotrolerantes. As leveduras isoladas de amostras coletadas na Península Antártica pela equipe de expedição do PROANTAR foram testadas para a produção de ASNase e L-glutaminase (GLNase). A partir desta triagem, a cepa Leucosporidium scottii L115 apresentou a maior atividade de ASNase (6,24 U g-1 dcw) com uma combinação de baixa atividade de GLNase (0,41 U g-1 dcw). A ASNase pertencente a L. scottii L115 (LsASNase) foi purificada 227 vezes com uma atividade específica de 137,01 U mg-1 a 37 ºC e com 0,93 U mg-1 de GLNase. A atividade máxima foi observada a pH 7,5 a 55 ºC. A enzima é um multímero que apresenta uma banda única de 54,5 kDa de peso molecular em condições redutoras e 462 kDa por cromatografia de exclusão molecular. A LsASNase é uma enzima glicosilada que apresentou uma banda menor a 25 kDa quando tratada com PGNase F. A cinética enzimática revela uma regulação alostérica da enzima e os parâmetros cinéticos foram determinados a 37º C, pH 7,0 como K0,5 = 233 µM, kcat = 54,7 s-1 e nH = 1,52 demonstrando uma cooperatividade positiva pela enzima e o substrato. A produção de ASNase por L. scottii L115 foi melhorada aplicando DoE para o desenvolvimento do meio de cultura. Os desenhos experimentais de PB e CDD forma usados para otimizar a produção de ASNase e forneceram os valores de nutrientes de 6,15 gL-1 de prolina, 28,34 gL-1 de sacarose e 15,61 gL-1 de glicerol para uma produção máxima. O meio sintético contendo as quantidades otimizadas foi adicionado com os sais: : KCl, 0.52 g L-1; MgSO4.7H2O, 0.52 g L-1; CuNO3.3H2O, 0.001 g L-1; ZnSO4.7H2O, 0.001 g L-1; FeSO4.7H2O, 0.001 g L-1.O meio otimizado produz 23.75 ULh-1 de ASNase em cultivo em frasco agitado. Além disso, L. scottii é caracterizada como uma levedura oleaginosa que acumula lipídios com um perfil adequado de ácidos graxos. A produção de ASNase e lipídios foi ampliada no biorreator de 1 L para avaliar a concentração celular inicial, fonte de carbono e taxa de transferência de oxigênio (kLa). Os experimentos foram realizados a 15ºC no biorreator BIOSTAT®Q plus (Sartorius Stedim) em modo batelada, utilizando 0,5 L da cultura de meio otimizado em tampão fosfato 50 mM pH 7,0. A concentração celular inicial foi avaliada em 1%, 3% e 5% (v / v). Sacarose e glicerol foram testados isoladamente para examinar se a combinação de ambos é obrigatória para produzir ASNase. Todos esses ensaios foram realizados em duplicado. O kLa foi avaliado através de um planejamento CCD na faixa de 1,42-123,0 h-1. O desempenho no biorreator mostrou a produtividade de 36,95 ULh-1 de ASNase sob condições otimizadas (temperatura de crescimento 15º C, X0: 5 g L-1, pH 7,0, 48 h, kLa 89-92 h-1). O cultivo de L. scottii L115 a 15ºC em sacarose e glicerol como fontes de carbono gera um perfil lipídico interessante, onde apresenta lipídios monoinsaturados e poliinsaturados
Descritores: Regiões Antárticas/etnologia
Asparaginase/análise
Leveduras
-Reatores Biológicos
Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico
Responsável: BR40.1 - DBD - Divisão de Biblioteca e Documentacão do Conjunto das Químicas
BR40.1; T660, S211p. 30100022453-F


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Id: biblio-889130
Autor: Dinarvand, Mojdeh; Rezaee, Malahat; Foroughi, Majid.
Título: Optimizing culture conditions for production of intra and extracellular inulinase and invertase from Aspergillus niger ATCC 20611 by response surface methodology (RSM)
Fonte: Braz. j. microbiol;48(3):427-441, July-Sept. 2017. tab, graf.
Idioma: en.
Resumo: Abstract The aim of this study was obtain a model that maximizes growth and production of inulinase and invertase by Aspergillus niger ATCC 20611, employing response surface methodology (RSM). The RSM with a five-variable and three-level central composite design (CCD) was employed to optimize the medium composition. Results showed that the experimental data could be appropriately fitted into a second-order polynomial model with a coefficient of determination (R2) more than 0.90 for all responses. This model adequately explained the data variation and represented the actual relationships between the parameters and responses. The pH and temperature value of the cultivation medium were the most significant variables and the effects of inoculum size and agitation speed were slightly lower. The intra-extracellular inulinase, invertase production and biomass content increased 10-32 fold in the optimized medium condition (pH 6.5, temperature 30 °C, 6% (v/v), inoculum size and 150 rpm agitation speed) by RSM compared with medium optimized through the one-factor-at-a-time method. The process development and intensification for simultaneous production of intra-extracellular inulinase (exo and endo inulinase) and invertase from A. niger could be used for industrial applications.
Descritores: Aspergillus niger/metabolismo
beta-Frutofuranosidase/biossíntese
Glicosídeo Hidrolases/biossíntese
Microbiologia Industrial/métodos
-Aspergillus niger/enzimologia
Aspergillus niger/genética
Aspergillus niger/crescimento & desenvolvimento
beta-Frutofuranosidase/genética
Reatores Biológicos/microbiologia
Meios de Cultura/química
Meios de Cultura/metabolismo
Fermentação
Glicosídeo Hidrolases/genética
Temperatura Ambiente
Tipo de Publ: Estudos de Avaliação
Responsável: BR1.1 - BIREME


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Id: biblio-840309
Autor: Pan, Long; Fang, Ya-kun; Zhou, Pei; Jin, Kui-qi; Gang, Wang; Liu, Yu-peng.
Título: Strategy of oxygen transfer coefficient control on the L-erythrulose fermentation by newly isolated Gluconobacter kondonii
Fonte: Electron. j. biotechnol;19(6):26-31, Nov. 2016. ilus.
Idioma: en.
Projeto: Key Project of Science and Technology of Henan Province.
Resumo: Background: The effect of diverse oxygen transfer coefficient on the L-erythrulose production from meso-erythritol by a newly isolated strain, Gluconobacter kondonii CGMCC8391 was investigated. In order to elucidate the effects of volumetric mass transfer coefficient (K La) on the fermentations, baffled and unbaffled flask cultures, and fed-batch cultures were developed in present work. Results: With the increase of the K La value in the fed-batch culture, L-erythrulose concentration, productivity and yield were significantly improved, while cell growth was not the best in the high K La. Thus, a two-stage oxygen supply control strategy was proposed, aimed at achieving high concentration and high productivity of L-erythrulose. During the first 12 h, Klawas controlled at 40.28 h-1 to obtain high value for cell growth, subsequently K La was controlled at 86.31 h-1 to allow for high L-erythrulose accumulation. Conclusions: Under optimal conditions, the L-erythrulose concentration, productivity, yield and DCW reached 207.9 ± 7.78 g/L, 6.50 g/L/h, 0.94 g/g, 2.68 ± 0.17 g/L, respectively. At the end of fermentation, the L-erythrulose concentration and productivity were higher than those in the previous similar reports.
Descritores: Gluconobacter/metabolismo
Oxigênio/metabolismo
Tetroses/biossíntese
-Reatores Biológicos
Eritritol
Fermentação
Curtume
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-836816
Autor: Morocho Jacome, Ana Lucia.
Título: Estudo do reaproveitamento de meio no cultivo de Arthrospira (Spirulina) platensis / Study of reuse of Arthrospira (Spirulina) platensis cultivation medium.
Fonte: São Paulo; s.n; ago. 2014. 143 p. tab, graf, ilus.
Idioma: pt.
Tese: Apresentada a Universidade de São Paulo para obtenção do grau de Doutor.
Resumo: Arthrosphira (Spirulina) platensis apresenta substâncias de interesse nas indústrias alimentícia, farmacêutica e cosmética. A produção industrial envolve uma quantidade muito grande de água e sua viabilidade deve contemplar o reuso do meio, visando uma diminuição de custos com nutrientes, bem como da poluição ambiental, tornando-se assim um processo sustentável. O presente trabalho teve como objetivo principal a avaliação do reaproveitamento do meio no cultivo de A. platensis usando tratamentos físico-químicos de floculação e adsorção. Para tanto, tal cianobactéria foi cultivada em fotobiorreator (FBR) tubular em processos de batelada alimentada e contínuo em intensidade luminosa de 120 µmol fótons m-2 s-1, sob controle de pH. Foram desenvolvidas técnicas de tratamento de meio de cultivo proveniente de processo descontínuo alimentado de A. platensis para a remoção de matéria orgânica (MO) e pigmentos (60 - 96 %), permitindo assim seu reuso em novos cultivos. A. platensis foi cultivada nos meios tratados utilizando frascos Erlenmeyer, com avaliação de parâmetros como concentração celular máxima (Xm), conteúdo de clorofila-a (Chl) e conteúdo de proteína na biomassa seca (PTN). No processo simultâneo de floculação e adsorção com carvão ativado em pó (CAP), foram testados dois agentes floculantes, cloreto férrico (F) e sulfato férrico (S) bem como diferentes tempos de contato. No processo simultâneo de floculação com F e adsorção com CAP, as condições ótimas foram: CAP = 24,4 mg L-1 e F = 20,3 mg L-1durante 30,4 min de tempo de contato; com obtenção de: Xm = 4893 ± 33 mg L-1, Chl = 24,3 ± 0,1 mg g-1, PTN = 36,1 ± 0,6 %. As condições ótimas de tratamento simultâneo de floculação com S e adsorção com CAP foram: CAP = 40,0 mg L-1 e S = 32,8 mg L-1 durante 36,1 min de tempo de contato, com obtenção de: Xm = 4863 ± 64 mg L-1, Chl = 24,5 ± 0,6 mg g-1, PTN = 60,1 ± 0,6 %. No processo sequencial de floculação com F seguido de adsorção com carvão ativado granulado (CAG), as condições ótimas foram atingidas com: CAG = 108,4 g e F = 10,0 mg L-1 durante 30,8 min de tempo de residência; obtendo-se: Xm = 3140 ± 77 mg L-1, Chl = 35,4 ± 0,2 mg g-1, PTN = 44,9 ± 0,0 %. Adicionalmente, os meios tratados nessas condições ótimas de cada tratamento, também foram testados em FBR tubulares, atingindo valores de Xm, Chl e PTN maiores do que os obtidos com meio padrão. Além disso, o processo simultâneo de cultivo celular em FBR tubulares e adsorção contínua do meio de cultivo exaurido em coluna de CAG removeu 51 - 79 % de MO e pigmentos. Foi demonstrado que uma proporção de 75 % de meio tratado no meio de alimentação não produz diminuição significativa de produtividade celular (PX) e os resultados foram: concentração celular em estado estacionário (Xs) de 1568 ± 15 mg L-1, PX = 941 mg L-1 d-1, PTN = 42,0 ± 0,6 %, com diminuição de 65 % no custo de meio de cultivo. Por fim, conclui-se que é viável a utilização de processos físico-químicos no tratamento de meio a ser reaproveitado no cultivo de A. platensis, inclusive em FBR tubulares, com apreciável incremento de clorofila-a e proteínas na biomassa obtida em meio tratado

Arthrospira (Spirulina) platensis have compounds of interest in the food, pharmaceutical and cosmetic industries. Industrial production involves high volumes of water and its viability should contemplate medium reuse, aiming to reduce not only nutrient costs, but also environmental pollution, thus becoming a sustainable process. This work had as main objective the evaluation of A. platensis culture medium reuse through the physicochemical treatments flocculation and adsorption. Thus, this cyanobacterium was cultivated in tubular photobioreactor (PBR) by fed-batch and continuous processes at light intensity 120 µmol photons m-2 s-1 under pH control. Treatment techniques were developed for culture medium from fed-batch process to properly removal of organic matter (OM) and pigments (60 - 96 %), thus allowing its reuse in new cultures. A. platensis was cultivated in treated medium using Erlenmeyer flasks, with the evaluation of parameters such as maximum cell concentration (Xm), chlorophyll content (Chl) and protein content in dry biomass (PTN). For simultaneous flocculation and adsorption with powdered activated carbon (PAC), two flocculants were used: ferric chloride (F) and ferric sulfate (S), as well as different contact times. In the simultaneous process of F flocculation and PAC adsorption, optimum conditions were: PAC = 24.4 mg L-1 and F = 20.3 mg L-1 for 30.4 min contact time; results were: Xm = 4893 ± 33 mg L-1, Chl = 24.3 ± 0.1 mg g-1, PTN = 36.1 ± 0.6 %. Optimal conditions in the simultaneous process of S flocculation and PAC adsorption were: PAC = 40.0 mg L-1 and S = 32.8 mg L-1 for 36.1 min contact time; results were: Xm = 4863 ± 64 mg L-1, Chl = 24.5 ± 0.6 mg g-1, PTN = 60.1 ± 0.6 %. In the sequential process of F flocculation followed by adsorption with granular activated carbon (GAC), optimal conditions were reached at GAC = 108.4 g and F = 10.0 mg L-1 for 30.8 min of residence time, at which Xm = 3140 ± 77 mg L-1, Chl = 35.4 ± 0.2 mg g-1 and PTNPTN = 44.9 ± 0.0 % were obtained. Moreover, medium treated at each optimal condition were also tested in tubular PBRs, reaching values of Xm, Chl and PTN higher than those obtained with standard medium. Furthermore, the simultaneous process of cell cultivation in tubular PBR and continuous adsorption of spent cultivation medium through GAC column removed 51 - 79 % of OM and pigments. It was showed that 75 % of treated medium in the feed medium does not cause significant decrease in cell productivity (PX) and results were: steady-state cell concentration (Xs) = 1568 ± 15 mg L-1, PX = 941 mg L-1 d-1, PTN = 42.0 ± 0.6 %, with 65 % reduction in medium price. At last, it can be inferred that the use of physicochemical processes in medium treatment is feasible for reuse in A. platensis cultivation, including that in tubular PBR, leading to considerable increase in chlorophyll and protein contents of the biomass obtained with treated medium
Descritores: Biomassa
Meios de Cultura/análise
Floculação
Spirulina/crescimento & desenvolvimento
-Adsorção
Reatores Biológicos
Microbiologia
Responsável: BR40.1 - DBD - Divisão de Biblioteca e Documentacão do Conjunto das Químicas
BR40.1; T 660.6, M867es. 30100021891-F



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