日本曲霉产β-D-呋喃果糖苷酶的固定化

Immobilization of β-Fructofuranosidase from Aspergillus japonicus

采用海藻酸钠包埋法、明胶-海藻酸钠复合包埋法和戊二醛-海藻酸钠共价交联法分别对日本曲霉来源的β-D-呋喃果糖苷酶进行固定化研究。实验结果发现:当海藻酸钠溶液浓度为3g/100mL,游离酶液酶活为800U/mL,CaCl2溶液浓度为1g/100mL,固定化时间为20min,制备的固定化酶酶活回收率为54.32%;添加浓度为3g/100mL明胶进行复合包埋后,其固定化酶酶活回收率达到69.23%;与0.3g/100mL戊二醛进行共价交联15min,制备的固定化酶酶活回收率为62.31%,反应10批相对酶活回收率仍在80%以上。从实际生产应用、固定化酶酶活、固定化酶的操作稳定性等方面综合比较,戊二醛-海藻酸钠交联法较佳。

The β-fructofuranosidase from Aspergillus japonicus were immobilized by sodium alginate embedding method,gelatin-sodium alginate embedding method and glutaraldehyde-sodium alginate crosslinking method,respectively.Results showed that when the concentration of sodium alginate was 3 g/100 mL,the enzyme activity was 800 U/mL,the concentration of CaCl2 solution was 1 g/100 mL,immobilized for 15 min,the enzyme recovery was 54.32%.After adding the gelatin concentration of which was 3 g/100 mL,the enzyme recovery reached 69.23%;The immobilized enzyme crosslinked with glutaraldehyde concentration of which was 0.3 g/100 mL for 15 min,the enzyme recovery was 62.31%.The immobilized enzyme produced by glutaraldehyde-sodium alginate crosslinking method was very stabilizing.The relative enzyme recovery was over 80%,after using for 10 times.Under the consideration of application in industrial production,operational stability of immobilized enzyme,the glutaraldehyde-sodium alginate crosslinking method was better.