Download Consulta: creatorFacets:"Pereira Jr,Nei" Registros recuperados: 6

Consulta: creatorFacets:"Pereira Jr,Nei"
Registros recuperados: 6
Data/hora: 09/06/2017 03:35:02
Effects of agitation and exogenous H2 on bioconversion of sugarcane bagasse into ethanol by
Clostridium thermocellum ATCC 27405
Provedor de dados: 69
Autores: Groposo,Claudia; Castro,Aline Machado de; Pereira Jr,Nei.
Background: The production of ethanol by a Consolidated Bioprocessing (CBP) strategy, which simultaneously combines
cellulase production, lignocellulosic biomass hydrolysis and fermentation of released sugars to ethanol in one bioreactor, is a
promising technology for cost reduction in the biological processing of biomass, specially using agroindustrial residues.
Clostridium thermocellum is an anaerobic, thermophilic, strictly fermentative gram positive bacterium that meets all the
requirements for CBP. Results: Ethanol concentration obtained in the non-stirred fermentation process in flasks with raw bagasse
was two times greater than that in the stirred system. The results observed using a pretreated sugarcane bagasse in non-stirred
flasks regarding...
Tipo: Journal article
Palavras-chave: Consolidated bioprocessing; Pretreated sugarcane bagasse; Raw sugarcane bagasse; Thermophilic.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000600009
Investigation of cultivation conditions for capsular polysaccharide production by Streptococcus
pneumoniae serotype 14
Provedor de dados: 69
Autores: Moura Leal,Maria de Lourdes; da Silva Gomes Pereira,Denise; Jessouroun,Ellen; Peixoto Gimenes Couto,Maria
Antonieta; Pereira Jr,Nei.
Streptococcus pneumoniae (pneumococcus) is among the most significant causes of bacterial disease in humans. Capsular
polysaccharide (CPS) production is essential for pneumococcal virulence. Pneumococcal CPS has been widely used as vaccine
antigen. This study is focused on the influence of culture conditions of Streptococcus pneumoniae serotype 14 as for developing
an industrial method for polysaccharide production. The pH proved to be a highly important variable in batchwise culture. Using
the pH control all glucose added was consumed resulting in a four-fold increase in polysaccharide productivity relative to
cultivation without pH control. S. pneumoniae is a lactic acid bacterium, so named for its primary metabolic byproduct (lactate),
which has an...
Tipo: Journal article
Palavras-chave: Polysaccharide capsular; Vaccine; Streptococcus pneumoniae.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000500006
Production and properties of the cellulase-free xylanase from Thermomyces lanuginosus IOC-4145
Provedor de dados: 58
Autores: Damaso,Mônica Caramez Triches; Andrade,Carolina M.M. Carvalho; Pereira Jr,Nei.
In recent years, xylanases have expanded their use in many processing industries, such as pulp and paper, food and textile.
Thermomyces lanuginosus IOC-4145 was able to produce a very high level of cellulase-free xylanase in shaken cultures using
corncob as substrate (500 U/mL). An optimization of the medium composition in submerged fermentation was carried out aiming
at a low cost medium composition for enzyme production. Statistical experiment design was employed for this purpose, pointing
out corncob as the most important parameter, which affects enzyme production. Additionally, the influence of several chemicals
on xylanase activity was investigated in the crude extract. A slight stimulation of the enzyme (5-15%) was achieved with NaCl
and urea, both...
Tipo: Journal article
Palavras-chave: Xylanases; Thermomyces lanuginosus; Corncob; Submerged fermentation; Medium optimization.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822002000400011
Simultaneous saccharification and fermentation process of different cellulosic substrates using a
recombinant Saccharomyces cerevisiae harbouring the β-glucosidase gene
Provedor de dados: 69
Autores: Ferreira,Verônica; Faber,Mariana de Oliveira; Mesquita,Sabrina da Silva; Pereira Jr,Nei.
In Brazil, the production of ethanol from sugarcane produces large amounts of lignocellulosic residues (bagasse and straw), which
have been driving research and development for the production of second generation ethanol. In the present work, a recombinant
Saccharomyces cerevisiae strain expressing the β-glucosidase gene from Humicola grisea was used for ethanol
production from three different cellulosic sources by simultaneous saccharification and fermentation. Initially, a enzymatic
pre-hydrolysis step was done with a solid:liquid ratio of 1:4, and an enzymatic load of 25 filter paper activity (FPU).g-1 of
cellulosic substrate. Using sugarcane bagasse pretreated cellulignin, crystalline cellulose and carboxymethyl cellulose, 51.7 g L-1,
41.7 g...
Tipo: Journal article
Palavras-chave: Bioethanol; Lignocellulosic biomass; Sugarcane bagasse derived cellulignin.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000200005
Sugar cane bagasse as feedstock for second generation ethanol production: Part I: Diluted acid
pretreatment optimization
Provedor de dados: 69
Autores: Vargas Betancur,Gabriel J; Pereira Jr,Nei.
Tons of sugar cane bagasse are produced in Brazil as waste of the sugar and ethanol industries. This lignocellulosic material is a
potential source for second-generation ethanol production. Diluted acid hydrolysis is one of the most efficient pretreatments for
hemicellulosic solubilization. The hydrolysate obtained is rich in xylose, which can be converted to ethanol by Pichia stipitis. This
work used a statistical approach and the severity factor to investigate the effects of factors associated with the diluted acid
hydrolysis process (acid concentration, solid:liquid ratio and time of exposure) on various response variables (xylose
concentration, hydrolysis yield, inhibitor concentration and hydrolysate fermentability). The severity factor had a strong...
Tipo: Journal article
Palavras-chave: Hemicellulose hydrolysis; Severity factor; Xylose.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000300010
Sugar cane bagasse as feedstock for second generation ethanol production: Part II: Hemicellulose
hydrolysate fermentability
Provedor de dados: 69
Autores: Betancur,Gabriel J. Vargas; Pereira Jr,Nei.
Sugar cane bagasse is produced in Brazil as waste of the sugar and ethanol industries. This lignocellulosic material is a potential
source for second-generation ethanol production; however a pretreatment stage is essential, which aims at removing the
hemicellulose component by disorganizing the lignocellulosic complex. In this work sugar cane bagasse was pretreated by diluted
acid hydrolysis resulting in xylose-rich hydrolysates, which could be fermented to ethanol by a strain of the yeast Pichia stipitis.
Statistical approach was used to investigate the effects of factors associated with the diluted acid hydrolysis process (acid
concentration, solid:liquid ratio and time of exposure) on the fermentability of different hydrolysates. The statistical...
Tipo: Journal article
Palavras-chave: Bioethanol; Pichia stipitis; Xylose fermentation.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500014