吸附交联法固定化蔗糖异构酶及其在异麦芽酮糖制备中的应用

Immobilization of Sucrose Isomerase by Adsorption and Crosslinking Method for the Synthesis of Isomaltulose

DOI：10.3969/j.issn.1673-1689.2019.04.016

中文关键词: 蔗糖异构酶 固定化 异麦芽酮糖

英文关键词: sucroseisomerase,immobilization,isomaltulose

基金项目:

摘要点击次数: 103

全文下载次数: 135

中文摘要:

以壳聚糖为载体、戊二醛为交联剂，采用吸附交联法对重组短小芽孢杆菌来源的蔗糖异构酶进行固定化。以表观酶活力回收率为指标，对壳聚糖浓度、戊二醛加量、游离酶加量、固定化时间等条件进行了优化；并考察了温度、pH、固定化酶加量、反应时间以及底物浓度等因素对固定化蔗糖异构酶转化生产异麦芽酮糖的影响。结果表明，最佳固定化条件为：壳聚糖质量浓度3 g/dL、戊二醛加量（体积分数）0.75%、酶加量50 U/g、固定化时间16 h，此时固定化酶活力回收率达到70.3%；最佳转化条件为：温度30 ℃、初始pH 4.5、酶用量15 U/g，转化10 h，蔗糖质量浓度600 g/L，异麦芽酮糖最大产物得率达到87.8%。在最佳的转化条件下连续转化16次，产物得率仍保持在87.52%，显示该固定化酶具有良好的操作稳定性及较高的异麦芽酮糖合成能力。

英文摘要:

Sucrose isomerase from the recombinant strain was immobilized on chitosan cross-linked with glutaral-dehyde. The effects of chitosan concentration，glutaraldehyde content，enzyme concentration，crosslinking time were investigated using the immobilized enzyme activity recovery rate as an index.，and the effects of temperature，pH，enzyme dosage，reaction time and substrate concentration on the production of isomaltulose by immobilized sucrose isomerase were also investigated. The immobilization efficiency reached up to 70.3% under the optimal condition of immobilization achieved with 3.0% of the chitosan，0.75% glutaraldehyde content，50 U/g chitosan beads and 16 h. The optimum conditions of the synthesis of isomaltulosewere as follows：reaction temperature 30 ℃，initial pH 4.5，enzyme concentration 15 U/g sucrose，conversation time 12 h，initial sucrose concentration 600 g/L. When the reaction was performed under this specified conditions，the isomaltulose yield reached the maximum of 87.8%. The yield ratio was still up to 87.52% after 16 times of continuous conversion and it shows a good operational stability and a high productivity of isomaltulose.

查看全文 查看/发表评论 下载PDF阅读器