Immobilization and stabilization of an endoxylanase from Bacillus subtilis (XynA) for xylooligosaccharides (XOs) production

Abstract

a b s t r a c tXylooligosaccharides (XOs) are small oligomers constituted by 2−10 units of xylan monomers, with important nutraceutical properties. They can be produced through hydrolysis of xylan catalyzed by an endoxylanase. The use of immobilized and stabilized enzymes may decrease the industrial process costs. In this study, XynA, a recombinant enzyme from B. subtilis, was immobilized in three different supports: agarose and chitosan activated with glyoxal groups and chitosan activated with glutaraldehyde. High immobilization yields were obtained, 100% for agarose-glyoxal and chitosan-glutaraldehyde, 82% for chitosan-glyoxal, with recovered activities of 42.7 (±1.3), 10.7 ± 0.8 and 53.6% (± 1.7), respectively. A great increase in the thermal stability of the enzyme (at 56 • C, pH 5.5) was achieved for the glyoxal derivatives: 75-fold for chitosan and 8600-fold for agarose. The great thermal stability obtained to the derivative agarose-glyoxal can be explained by the enzyme immobilization through lysine residues located in unstable sites of the protein structure. The agarose-glyoxal derivative was tested in the production of XOs (X2, X3 and X4) from soluble and conventional birchwood xylan, reaching approximately 20% of conversion in 3 h and 23% in 24 h, without the undesirable xylose production. After 10 cycles of hydrolysis, the conversion remained almost unchanged.

Immobilization of Recombinant Endo‐1,4‐β‐xylanase on Ordered Mesoporous Matrices for Xylooligosaccharides Production

“…This is due to adsorption on support increases the stability or conformational rigidity of enzyme. A similar increase in optimum temperature range has been reported for endoxylanase immobilized on agarose‐glyoxal and chitosan‐glutaraldehyde and Nickel‐chelate Eupergit C, entrapped in chitosan chitin and PEG Net‐Cloth, adsorbed on Aluminum hydroxide particles, covalently bound to glyoxyl‐agarose and cyanuric chloride activated magnetic nanoparticles, bifunctional xylanase (ATXX) immobilized on carbon‐coated chitosan nanoparticles and xylanase immobilized on mesoporous silica coated chitosan . The increase in optimal temperature for activity of xylanase is independent of type of immobilization as both non‐covalent adsorption and covalent immobilization resulted in increase of optimal temperature.…”

“…CMK‐3 showed higher IY (> 25%) at high XynC load (64 U/10 mg of support) when compared with SBA‐15 and ZMF‐127 matrices (< 15%) (Figure S3a). Endoxylanase from B. subtilis immobilized on agarose activated with glyoxal groups had the percent of IY and RA of 100 and 43.1±2.7, respectively . Commercial xylanase (Novozyme) immobilized on epoxy‐chitosan showed 100% IY and 64.2% RA …”

“…Among these three types of materials, CMK‐3 retained more initial activity since XynC and CMK‐3 interaction is mostly hydrophobic compared to SBA‐15 and ZMF‐127 which are more likely electro statistics . Endoxylanase (XynA) from B. subtilis immobilized on agarose activated with glyoxal groups and endoxylanase from S. halstedii immobilized on glyoxyl‐agarose have been reported to retain initial activity for 10 cycles. Xylanase from P. occitanis Pol6 immobilized on Nickel‐chelate Eupergit C has been reported to retain 50% ofinitial activity after 5 cycles .…”

Luffa cylindrica sponges as a thermally and chemically stable support for Aspergillus niger lipase

“…Numerous literature reports indicate that natural‐origin biopolymers are useful and effective supports for enzyme immobilization . They are characterized by biodegradability, biocompatibility, and high affinity to peptides, including enzymes.…”

An Innovative Biocatalyst for Continuous 2G Ethanol Production from Xylo-Oligomers by Saccharomyces cerevisiae through Simultaneous Hydrolysis, Isomerization, and Fermentation (SHIF)

“…Birchwood xylan, which is a heteropolymer composed of long chains, was first hydrolyzed to smaller xylo-oligomers by the action of recombinant endoxylanase of Bacillus subtilis (XynA) in order to increase the concentration of xylo-oligomers with smaller chains that may diffuse into the catalyst beads [28]. This step was carried out to make xylan more similar to lignocellulosic hydrolysates obtained from the pretreatment of biomass (data not shown).…”