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1.
Food Chem ; 338: 128045, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33091987

RESUMO

A factorial design with a duplicate in the central point was used to investigate the effect of treating arabica coffee beans with asparaginase. The investigated factors were enzymatic load (1000 and 5000 ASNU/Kg), water percentage (30 and 90%), and hydrolysis time (1 and 3 h). The acrylamide content was determined by UPLC-MS/MS, and the caffeic acid, chlorogenic acid and caffeine concentrations were determined by HPLC-DAD. The statistical analysis was carried out in the R platform using RStudio graphical interface. The results indicated the importance of coffee bean pretreatment with steam, and that the enzyme load reduced the acrylamide content to 65 mg/kg in coffee beans. The predicted reduction was obtained with hydrolysis time of 2 h, water content of 90%, and asparaginase load of 5000 ASNU/kg. The asparaginase treatment did not influence the major bioactive compounds in coffee.


Assuntos
Acrilamida/análise , Asparaginase/metabolismo , Ácidos Cafeicos/análise , Cafeína/análise , Ácido Clorogênico/análise , Café/metabolismo , Ácidos Cafeicos/isolamento & purificação , Cafeína/isolamento & purificação , Ácido Clorogênico/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Café/química , Hidrólise , Extração em Fase Sólida , Espectrometria de Massas em Tandem
2.
Ciênc. rural ; 46(4): 755-761, Apr. 2016. tab, graf
Artigo em Português | LILACS | ID: lil-775149

RESUMO

RESUMO: Neste trabalho, foi avaliado o desempenho de duas linhagens de Aspergillus niger (mutante 11T53A14 e selvagem C) previamente selecionadas como promissoras para a produção de lipases, utilizando meios de cultivo formulados a partir da torta de dendê (palmiste) e da borra alcalina do refino do óleo de dendê (borra de dendê), resíduos provenientes da agroindústria do óleo de dendê (palma) por fermentação em estado sólido (FES). Os experimentos de produção da enzima em FES foram conduzidos em colunas aeradas, incubadas em banho-maria a 32ºC com entrada controlada de ar não umedecido de 1,0vvm. Os melhores resultados foram obtidos com a cepa mutante A. niger 11T53A14 em meio contendo torta de dendê umedecida com solução sulfato de amônio (1,2%) e com a adição de 3% da borra de dendê. O valor máximo da atividade da lipase neste meio foi de 72,57U gss-1 em 48 horas. Esse valor foi 47,5% superior ao obtido no meio sem a borra de dendê. A comparação do desempenho da cepa mutante com a cepa selvagem mostrou que o meio composto por torta de dendê adicionado com sulfato de amônio e borra de dendê induziu ambas as linhagens a produzir lipases com bons níveis de atividade, além de reduzir o tempo de processo de fermentação.


ABSTRACT: In this paper it was evaluated the performance of two strains of Aspergillus niger (mutant 11T53A14 and wild type C) previously selected as promising for lipase production, from cultivation media formulated from palm kernel cake (kernel) and alkaline sludge from refining were evaluated palm oil (palm oil sludge), palm oil (palm) waste industrialization by solid state fermentation (SSF). Experiments of enzyme production in SSF were conducted in aerated columns, incubated in a water bath at 32°C with controlled inlet of 1.0vvm. The best results were obtained with the mutant strain A. niger 11T53A14 in medium containing palm kernel cake moistened with a solution of ammonium sulfate (1.2%) and with the addition of 3% of palm oil sludge. The maximum lipase activity in this medium was 72.57U gdw-1 in 48 hours and 47.5% higher than in the medium without sludge palm. A comparison of the performance of the mutant strain with the wild-type strain showed that the medium composed of palm kernel cake added with ammonium sulfate and blurs palm induced both strains to produce lipases with good activity levels and reduced the time of the fermentation process.

3.
Braz J Microbiol ; 44(2): 569-76, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24294256

RESUMO

The production of xylanase, ß-xylosidase, ferulic acid esterase and ß-glucosidase by Aspergillus awamori 2B.361 U2/1, a hyper producer of glucoamylase and pectinase, was evaluated using selected conditions regarding nitrogen nutrition. Submerged cultivations were carried out at 30 °C and 200 rpm in growth media containing 30 g wheat bran/L as main carbon source and either yeast extract, ammonium sulfate, sodium nitrate or urea, as nitrogen sources; in all cases it was used a fixed molar carbon to molar nitrogen concentration of 10.3. The use of poor nitrogen sources favored the accumulation of xylanase, ß-xylosidase and ferulic acid esterase to a peak concentrations of 44,880; 640 and 118 U/L, respectively, for sodium nitrate and of 34,580, 685 and 170 U/L, respectively, for urea. However, the highest ß-glucosidase accumulation of 10,470 U/L was observed when the rich organic nitrogen source yeast extract was used. The maxima accumulation of filter paper activity, xylanase, ß-xylosidase, ferulic acid esterase and ß-glucosidase by A. awamori 2B.361 U2/1 was compared to that produced by Trichoderma reesei Rut-C30. The level of ß-glucosidase was over 17-fold higher for the Aspergillus strain, whereas the levels of xylanase and ß-xylosidase were over 2-fold higher. This strain also produced ferulic acid esterase (170 U/L), which was not detected in the T. reesei culture.


Assuntos
Aspergillus/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Xilosidases/metabolismo , beta-Glucosidase/metabolismo , Aspergillus/genética , Aspergillus/crescimento & desenvolvimento , Carbono/metabolismo , Meios de Cultura/química , Nitrogênio/metabolismo , Temperatura
4.
Braz. j. microbiol ; 44(2): 569-576, 2013. graf, tab
Artigo em Inglês | LILACS | ID: lil-688590

RESUMO

The production of xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by Aspergillus awamori 2B.361 U2/1, a hyper producer of glucoamylase and pectinase, was evaluated using selected conditions regarding nitrogen nutrition. Submerged cultivations were carried out at 30 ºC and 200 rpm in growth media containing 30 g wheat bran/L as main carbon source and either yeast extract, ammonium sulfate, sodium nitrate or urea, as nitrogen sources; in all cases it was used a fixed molar carbon to molar nitrogen concentration of 10.3. The use of poor nitrogen sources favored the accumulation of xylanase, β-xylosidase and ferulic acid esterase to a peak concentrations of 44,880; 640 and 118 U/L, respectively, for sodium nitrate and of 34,580, 685 and 170 U/L, respectively, for urea. However, the highest β-glucosidase accumulation of 10,470 U/L was observed when the rich organic nitrogen source yeast extract was used. The maxima accumulation of filter paper activity, xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by A. awamori 2B.361 U2/1 was compared to that produced by Trichoderma reesei Rut-C30. The level of β-glucosidase was over 17-fold higher for the Aspergillus strain, whereas the levels of xylanase and β-xylosidase were over 2-fold higher. This strain also produced ferulic acid esterase (170 U/L), which was not detected in the T. reesei culture.


Assuntos
Aspergillus/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Xilosidases/metabolismo , beta-Glucosidase/metabolismo , Aspergillus/genética , Aspergillus/crescimento & desenvolvimento , Carbono/metabolismo , Meios de Cultura/química , Nitrogênio/metabolismo , Temperatura
5.
Bioresour Technol ; 101(13): 4820-5, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20022746

RESUMO

The National Alcohol Program--PróAlcool, created by the government of Brazil in 1975 resulted less dependency on fossil fuels. The addition of 25% ethanol to gasoline reduced the import of 550 million barrels oil and also reduced the emission CO(2) by 110 million tons. Today, 44% of the Brazilian energy matrix is renewable and 13.5% is derived from sugarcane. Brazil has a land area of 851 million hectares, of which 54% are preserved, including the Amazon forest (350 million hectares). From the land available for agriculture (340 million hectares), only 0.9% is occupied by sugarcane as energy crop, showing a great expansion potential. Studies have shown that in the coming years, ethanol yield per hectare of sugarcane, which presently is 6000 L/ha, could reach 10,000 L/ha, if 50% of the produced bagasse would be converted to ethanol. This article describes the efforts of different Brazilian institutions and research groups on second generation bioethanol production, especially from sugarcane bagasse.


Assuntos
Biotecnologia/tendências , Etanol/química , Lignina/química , Ração Animal , Animais , Biomassa , Biotecnologia/métodos , Brasil , Celulose/química , Conservação dos Recursos Naturais , Fontes Geradoras de Energia , Hidrólise , Saccharum
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