title: Co-immobilization of fungal endo-xylanase and α-L-arabinofuranosidase in glyoxyl agarose for improved hydrolysis of arabinoxylan.
abstract: Plant cell-wall arabinoxylans have a complex structure that requires the action of a pool of debranching (arabinofuranosidases) and depolymerizing enzymes (endo-xylanase). Two Aspergillus nidulans strains over-secreting endo-xylanase and arabinofuranosidase were inoculated in defined 2% maltose-minimum medium resulting in the simultaneously production of these enzymes. To study the synergistic hydrolysis was used arabinoxylan with 41% of arabinose and 59% of xylose residues. Thus, it was adopted different approaches to arabinoxylan hydrolysis using immobilized arabinofuranosidase and endo-xylanase: (i) endo-xylanase immobilized on glyoxyl agarose; (ii) arabinofuranosidase immobilized on glyoxyl agarose; (T1) hydrolysis of arabinoxylan with arabinofuranosidase immobilized on glyoxyl agarose for debranching, followed by a second hydrolysis with endo-xylanase immobilized on glyoxyl agarose; (T2) hydrolysis using (i) and (ii) simultaneously; and (T3) hydrolysis of arabinoxylan with endo-xylanase and arabinofuranosidase co-immobilized on glyoxyl agarose. It was concluded that arabinoxylan hydrolysis using two derivatives simultaneously (T2) showed greater hydrolytic efficiency and consequently a higher products yield. However, the hydrolysis with multi-enzymatic derivative (T3) results in direct release of xylose and arabinose from a complex substrate as arabinoxylan, which is a great advantage as biotechnological application of this derivative, especially regarding the application of biofuels, since these monosaccharides are readily assimilable for fermentation and ethanol production.
authors.affiliation: Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: André Ricardo de Lima
authors.initials: AR
authors.lastname: Damásio
authors.forename: Benevides C
authors.initials: BC
authors.lastname: Pessela
authors.forename: Tony Márcio
authors.initials: TM
authors.lastname: da Silva
authors.forename: Luis Henrique Souza
authors.initials: LH
authors.lastname: Guimarães
authors.forename: João Atílio
authors.initials: JA
authors.lastname: Jorge
authors.forename: Jose Manuel
authors.initials: JM
authors.lastname: Guisán
authors.forename: Maria de Lourdes T M
authors.initials: Mde L
authors.lastname: Polizeli
mesh_terms: D001089:Arabinose / Q000737:chemistry; D001233:Aspergillus nidulans / Q000737:chemistry / Q000201:enzymology*; D003470:Culture Media; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry* / Q000302:isolation & purification; D005285:Fermentation; D005656:Fungal Proteins / Q000737:chemistry* / Q000302:isolation & purification; D006026:Glycoside Hydrolases / Q000737:chemistry* / Q000302:isolation & purification; D006038:Glyoxylates / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D055767:Immobilized Proteins / Q000737:chemistry* / Q000302:isolation & purification; D007700:Kinetics; D012685:Sepharose / Q000737:chemistry; D013379:Substrate Specificity; D013696:Temperature; D014990:Xylans / Q000737:chemistry*; D014994:Xylose / Q000737:chemistry
chemical_list: D003470:Culture Media; D005656:Fungal Proteins; D006038:Glyoxylates; D055767:Immobilized Proteins; D014990:Xylans; C070399:glyoxyl agarose; D012685:Sepharose; C085118:arabinoxylan; D014994:Xylose; D001089:Arabinose; D006026:Glycoside Hydrolases; C019713:alpha-N-arabinofuranosidase; D043364:Endo-1,4-beta Xylanases
keywords: agarose; arabinofuranosidase; arabinoxylan; co-immobilization; endo-xylanase