新型β-甘露聚糖酶制备葡甘寡糖工艺优化

为探索能应用于葡甘寡糖制备的新型β-甘露聚糖酶,利用半纤维素降解高效菌株Bacillus subtilis BE-91高产的β-甘露聚糖酶水解魔芋胶(纯度95%)。在单因素试验的基础上,采用四因素三水平的正交试验优化魔芋胶酶解工艺条件,薄层层析法定性分析酶解产物。结果表明:正交试验的最佳酶解工艺组合为魔芋胶质量浓度0.33 g/100 m L、加酶量6 U/g、酶解时间1 h、酶解温度60℃,在该条件下魔芋胶水解率为35.96%;β-甘露聚糖酶水解魔芋胶产物为二糖以上的寡糖,且主要介于二糖与六糖之间。该新型β-甘露聚糖酶用于葡甘寡糖制备,其工艺具有加酶量少、酶解时间短、产品纯度高等优势,在功能性食品制备方面具有广阔的应用前景。

Optimization of the Process Conditions on Preparation of Glucomanno-Oligosaccharides Using a Novel β-Mannanase

This study explored the preparation of glucomanno-oligosaccharides by the hydrolysis of konjac gum with
purity more than 95% using a new high-yield β-mannanase with high degradation efficiency of hemicellulose secreted by
Bacillus subtilis BE-91. Based on one-factor-at-a-time experiments, a four-variable, three-level orthogonal array design was
applied to optimize the hydrolysis process of konjac gum, and thin layer chromatography (TLC) was used to qualitatively
analyze the products. Results showed that the optimal experimental conditions that provided maximum hydrolysis efficiency
(35.96%) were determined as follows: konjac gum concentration, 0.33 g/100 mL; β-mannanase dosage, 6 U/g; hydrolysis
time, 1 h; and hydrolysis temperature, 60 ℃. The hydrolysis rate of the konjac gum obtained under these optimal conditions
was 35.96%. The hydrolysis products were mostly oligosaccharides with a polymerization degree of 2–6. The enzymatic
approach to the preparation of glucomanno-oligosaccharides possesses the advantages of lower enzyme consumption, shorter
hydrolysis time, and higher-purity products which have broad application prospects in the preparation of functional foods.