초록
The enzymatic synthesis of fructooligosaccharides (FOS) was carried out using a partially purified β-fructofuranosidase from the commercial enzyme preparation Viscozyme L. Partial purification of β-fructofuranosidase from Viscozyme L was done by batch adsorption using ion-exchange resin DEAE-Sepharose, showing a 6-fold increase in specific activity. The biocatalyst was then covalently immobilized on glutaraldehyde-activated chitosan particles. Thermal stability of the biocatalyst was evaluated at 50<SUP>o</SUP>C and 60<SUP>o</SUP>C, being around 100 times higher at 60<SUP>o</SUP>C when compared to the free enzyme. The immobilized biocatalyst was reused 50 times for FOS production (100min per batch at 50<SUP>o</SUP>C and pH 5.5) without significant loss of activity. The average yield (grams of FOS per grams of initial sucrose) was 55%. The immobilization process combined with partial purification method resulted in a derivative with activity of 1230U<SUB>t</SUB>/g, which is among the best for FOS production.