Immobilization of β - fructofuranosidase Fru6 by macroporous resin MI-BN4 and its application in catalytic synthesis of fructo-oligosaccharides

In order to reduce the running cost, immobilization of β-fructofuranosidase Fru6 was investigated for fructo-oligosaccharide preparation. Fru6 was immobilized by multi-functional resin MI-BN4 and the immobilization condition was optimized. The enzymatic properties, the ability to catalyze fructo-oligosaccharide and the capacity for reusing immobilized Fru6 were explored. When adsorbed for 6 h at 25 °C with 40 U enzyme, an immobilized enzyme with 205.7U/g activity was obtained, which had 95.2% recovery rate of enzyme activity and absorbed 0.6mg/g dry resin protein. Compared with free enzyme, the fructo-oligosaccharides conversion rate with immobilized Fru6 increased from 62% to 72% and the yield of fructo-oligosaccharides slightly reduced. Besides, the immobilized Fru6 could be reused for 12 times. Overall, the immobilized Fru6 has high enzyme activity recovery rate and good catalytic ability, which lays a foundation for fructo-oligosaccharides production.