Immobilization of the β-fructofuranosidase from Xanthophyllomyces dendrorhous by entrapment in polyvinyl alcohol and its application to neo-fructooligosaccharides production

Abstract

The β-fructofuranosidase (Xd-INV) from the basidiomycota yeast Xanthophyllomyces dendrorhous (formerly Phaffia rhodozyma) is unique in its ability to synthesize neo-fructooligosaccharides (neo-FOS). In order to facilitate its industrial application, the recombinant enzyme expressed in Pichia pastoris (pXd-INV) was immobilized by entrapment in polyvinyl alcohol (PVA) hydrogels. The encapsulation efficiency exceeded 80%. The PVA lenticular particles of immobilized pXd-INV were stable up to approximately 40 °C. Using 600 g/L sucrose, the immobilized biocatalyst synthesized 18.9% (w/w) FOS (59.1 g/L of neokestose, 30.2 g/L of 1-kestose, 11.6 g/L of neonystose and 12.6 g/L of blastose). The operational stability of PVA-immobilized biocatalyst was assayed in a batch reactor at 30 °C. The enzyme preserved its initial activity during at least 7 cycles of 26 h.