Biocatalytic process for synthesis of oxidized xylooligo­sacharides from xylan

Abstract

Pyrroloquinoline quinone dependent glucose dehydrogenases (PQQ-GDH) are attractive catalysts because of their wide substrate specificity and non-diffusible cofactor. PQQ-GDH from Acinetobacter sp. is capable to oxidize xylobiose or xylotetraose to the corresponding aldonic acid. The PQQ-GDH covalently immobilized on silica gel by cross-linking with glu­taraldehyde exhibits higher thermostability compared with the free enzyme. The pro­cedure of dichlorophenol indophenol mediated oxidation of xylobiose and xylotetraose in the presence of immobilized PQQ-GDH and laccase was developed.