Análise de celulases e xilanases por fungo isolado a partir do bioma cerrado

• Autor(a) principal: Pereira, Douglas Endrigo Perez
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/00130000037p6
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/3587
• topic: Aspegillus niger; Celulases; Xilanases; Zimograma; Bioma cerradp; Cellulases; Xylanases; Zymogram; Cerrado Biome; BIOFISICA::BIOFISICA MOLECULAR

Lignocellulosic biomass is constituted by cellulose, hemicellulose and lignin in the plant cell walls. The conversion of lignocellulose to fermentable sugars mainly depends on the action of a complex of enzymes that hydrolyze cellulose and hemicellulose. This study was to analyze the production of cellulases and xylanases by fungi isolated from soil and decaying material in Cerrado. Initially, the fungi were analyzed for cellulase production capacity among the fungal cellulase-producing fungus capable of producing the highest levels of cellulase was selected for the experiments of xylanase and cellulase production by submerged fermentation and biochemical analysis of the enzyme secreted. Among the isolated fungi, fungus called IFBMD01 was that higher activity of cellulase in the supernatant when cultivated with wheat bran as carbon source. This was identified as Aspergillus cf niger. The enzymes studied with their respective results were: FPase with better production time of 7 days, showing activity of 0.10 U / mL, optimum pH 5.5, optimum temperature of 60 ° C; CMCase with better time production 6 days, showing activity of 8.19 U / mL, pH optimum of 5, optimum temperature of 70 º C; Avicelase with better production time of 9 days, showing activity of 0.01 U / mL, pH optimum of 5.5 and optimum temperature of 60 ° C; xylanase, with better production time 3 days, showing activity of 35.5 U / mL, and the optimum pH of 5 and the optimum temperature of 50 ° C, the β-Glycosidase, with higher production on the sixth day showing activity of 0.98 U / mL, with the optimum pH 5 and optimum temperature of 60 ° C. The activity of β-glucosidase showing in the culture supernatant was influenced by the ions Mn2 +, NH4, K +, Mg2 +, Ca2 +, Ba2 +, Al3 +, Na +, and Co2+, as well as EDTA, glucose, xylose and cellobiose. In the culture supernatant of the fungus A. niger IFBMD01 grown on FT for 3 and 6 days protein bands were visualized with activity against xylan and CMC molecular weight be 30 to be 66 kDa.