Immobilization and stabilization of acetyl xylan esteraseof Aspergillus nidulans

Abstract

[Excerpt] Acetyl xylan esterase (EC 3.1.1.72) are enzymes that cleave the ester bonds of the O-acetyl groups of the xylan backbone to create new sites for subsequent hydrolysis of other enzymes, such as endoxylanases (BIELY et al., 2014). D-xylose is one of the main constituents of xylan, the main class of hemicellulose. To degrade this structure, it is necessary that enzymatic hydrolysis occurs synergistically with xylanolytic enzymes, such as endo-beta-1,4-xylanases, β-xylosidases, α-Larabinofuranosidases, α-glucuronidases, feruloyl esterase and acetyl xylan esterase (AXE) (POLIZELI et al., 2016). The use of enzymes in their free form is expensive and expensive, in addition to some problems such as low stability, sensitivity to process conditions, and difficulties in recovering the products and recycling the enzyme from the reaction medium (MATEO et al., 2007). To assist in these difficulties, the immobilization process becomes essential for applying enzymes in industrial processes, as it contributes to stabilization reuse of the enzyme in several cycles, reducing the cost of the biocatalyst (SANTOS et al., 2015). In the present work, we purify, characterize an acetyl xylan esterase (AxeCE3) from Aspergillus nidulans and successfully immobilized in an activated agarose matrix with different reactive groups: monoaminoethyl-N-ethyl (MANAE), Glyoxyl and Glyoxyl-Iminodiacetic acid (IDA).