Bioquímica e Biologia Molecular
URI permanente desta comunidadehttps://locus.ufv.br/handle/123456789/11837
Navegar
3 resultados
Resultados da Pesquisa
Item Optimization of Endoglucanase and Xylanase activities from fusarium verticillioides for simultaneous saccharification and fermentation of sugarcane bagasse(Applied Biochemistry and Biotechnology, 2013-10-30) Almeida, Maíra N. de; Guimarães, Valéria M.; Falkoski, Daniel L.; Paes, Guilherme B. T.; Ribeiro Jr., José Ivo; Visser, Evan M.; Alfenas, Rafael F.; Pereira, Olinto L.; Rezende, Sebastião T. deEnzymatic hydrolysis is an important but expensive step in the production of ethanol from biomass. Thus, the production of efficient enzymatic cocktails is of great interest for this biotechnological application. The production of endoglucanase and xylanase activites from F. verticillioides were optimized in a factorial design (25) followed by a CCDR design. Endoglucanase and xylanase activities increased from 2.8 to 8.0 U/mL and from 13.4 to 114 U/mL, respectively. The optimal pH and temperature were determined for endoglucanase (5.6, 80 °C), cellobiase (5.6, 60 °C), FPase (6.0, 55 °C) and xylanase (7.0, 50 °C). The optimized crude extract was applied in saccharification and fermentation of sugarcane bagasse from which 9.7 g/L of ethanol was produced at an ethanol/biomass yield of 0.19.Item Direct ethanol production from glucose, xylose and sugarcane bagasse by the corn endophytic fungi Fusarium verticillioides and Acremonium zeae(Journal of Biotechnology, 2013-07-31) Almeida, Maíra N. de; Guimarães, Valéria M.; Falkoski, Daniel L.; Visser, Evan M.; Siqueira, Germano A.; Milagres, Adriane M.F.; Rezende, Sebastião T. deProduction of ethanol with two corn endophytic fungi, Fusarium verticillioides and Acremonium zeae, was studied. The yield of ethanol from glucose, xylose and a mixture of both sugars were 0.47, 0.46 and 0.50 g/g ethanol/sugar for F. verticillioides and 0.37, 0.39 and 0.48 g/g ethanol/sugar for A. zeae. Both fungi were able to co-ferment glucose and xylose. Ethanol production from 40 g/L of pre-treated sugarcane bagasse was 4.6 and 3.9 g/L for F. verticillioides and A. zeae, respectively, yielding 0.31 g/g of ethanol per consumed sugar. Both fungi studied were capable of co-fermenting glucose and xylose at high yields. Moreover, they were able to produce ethanol directly from lignocellulosic biomass, demonstrating to be suitable microorganisms for consolidated bioprocessing.Item Characteristics of free endoglucanase and glycosidases multienzyme complex from Fusarium verticillioides(Bioresource Technology, 2013-06-08) Almeida, Maíra N.de; Falkoski, Daniel L.; Guimarães, Valéria M.; Ramos, Humberto Josué de O.; Visser, Evan M.; Maitan-Alfenas, Gabriela P.; Rezende, Sebastião T. deA novel multienzyme complex, E1 C , and a free endoglucanase, E2 (GH5), from Fusarium verticillioides were purified. The E1 C contained two endoglucanases (GH6 and GH10), one cellobiohydrolase (GH7) and one xylanase (GH10). Maximum activity was observed at 80 °C for both enzymes and they were thermostable at 50 and 60 °C. The activation energies for E1 C and E2 were 21.3 and 27.5 kJ/mol, respectively. The K M for E1 C was 10.25 g/L while for E2 was 6.58 g/L. Both E1 C and E2 were activated by Mn 2+ and CoCl 2 while they were inhibited by SDS, CuSO 4 , FeCl 3 , AgNO 4 , ZnSO 4 and HgCl 2 . E1 C and E2 presented endo-b-1,3–1,4-glucanase activity. E1 C presented crescent activity towards cellopentaose, cellotetraose and cellotriose. E2 hydrolyzed the substrates cellopentaose, cellotetraose and cellotriose with the same efficiency. E1 C showed a higher stability and a better hydrolysis performance than E2, suggesting advantages resulting from the physical interaction between proteins.