Upgrading of Biomass Monosaccharides by Immobilized Glucose Dehydrogenase and Xylose Dehydrogenase. Issue 22 (16th October 2018)

• Record Type: Journal Article
• Authors: Zdarta, Jakub; Pinelo, Manuel; Jesionowski, Teofil; Meyer, Anne S.
• Is Part Of: ChemCatChem. Volume 10:Issue 22(2018)
• Page Start: 5164
• Page End: 5173
• Publication Date: 2018-10-16
• Subjects: glucose dehydrogenase -- xylose dehydrogenase -- enzyme immobilization -- silica -- biomass conversion; Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.201801335
• Languages: English
• ISSNs: 1867-3880

Abstract

Abstract: Direct upgrading and separation of the monosaccharides from biomass liquors is an overlooked area. In this work we demonstrate enzymatic production of gluconic acid and xylonic acid from glucose and xylose present in pretreated birchwood liquor by glucose dehydrogenase (GDH, EC 1.1.1.47) and xylose dehydrogenase (XDH, EC 1.1.1.175), respectively. The biocatalytic conversions were compared using two different kinds of silica support materials (silica nanoparticles (nanoSiO2 ) and porous silica particles with hexagonal pores (SBA 15 silica) for enzyme immobilization. Upon immobilization, both enzymes showed significant improvement in their thermal stability and robustness at alkaline pH and exhibited over 50 % activity even at pH 10 and 60 °C on both immobilization matrices. When compared to free enzymes at 45 °C, GDH immobilized on nanoSiO2 and SBA silica displayed a 4.5 and 7.25 fold increase in half‐life, respectively, whilst XDH immobilized on nanoSiO2 and SBA showed a 4.7 and 9.5 fold improvement in half‐life, respectively. Additionally, after five reaction cycles both nanoSiO2 GDH and nanoSiO2 XDH retained more than 40 % activity and GDH and XDH immobilized on SBA silica maintained around 50 % of their initial activity resulting in about 1.5–1.6 fold increase in biocatalytic productivity compared to the free enzymes. Abstract : Fixed is best : Immobilization of glucose and xylose dehydrogenase using silica‐based support materials improved enzymes stability and reusability as well as enhanced efficient conversion of biomass components in bioreactors, under mild conditions.