Immobilisation of glycosidases from commercial preparation on magnetic beads. Part 1. Characterisation of immobilised glycosidases with a particular emphasis on β-glucosidase

Abstract

A major fraction of terpenes in wines is conjugated to various sugars representing a significant reservoir of aromatic precursors. To promote the release of these aromatic precursors, certain enzymes, such as β-glucosidase, α-arabinosidase and α-rhamnosidase, are necessary. The aim of this work was to develop an immobilised biocatalyst with multiple glycosidical activities from commercial Aspergillus niger glycosidases. Immobilised enzymes offer well-known advantages over soluble enzyme preparations, including an enhanced control of the reaction process and enzyme-free products. The immobilisation was performed using carbodiimide on commercially available magnetic beads.The immobilised glycosidases were compared with the free enzymes with respect to pH, temperature, ethanol content, glucose and fructose concentrations, stability over time and kinetic parameters (KM and kcat). The stability parameters of the immobilised enzymes in acid buffer and wine were very high, and there were no shifts in the enzyme activities under different characteristics. The results are promising for future technological applications of immobilised enzymes in wine-making.