摘要
为了探寻利用复合酶制备低聚甘露糖的最佳工艺,基于β-甘露聚糖酶和β-1,4-内切葡聚糖酶对魔芋精粉的水解具有协同作用的原理,以耐高温的重组β-甘露聚糖酶(re Au Man5AN3C3)为主,辅以不同活性单位的高催化活性的重组β-1,4-内切葡聚糖酶(re Au Cel12A)对魔芋精粉进行水解。通过研究不同酶的添加比例、酶解p H值、酶解时间、酶解温度和底物浓度等因素,获得复合酶最佳的复配比例及酶解工艺条件。同时研究了保护剂对复合酶稳定性的影响。研究结果表明:复合酶解魔芋精粉制备低聚甘露糖的最佳工艺条件为:用去离子水配制的30 g/L魔芋胶溶液,re Au Man5AN3C3和re Au Cel12A配比为1∶1.5(前者为60 U/g魔芋精粉),水解温度为60℃,水解时间为6 h,在此条件下魔芋精粉的水解率可达65%。薄层层析分析结果显示魔芋精粉经酶水解后产物主要是二糖以上的寡糖,且主要介于二糖与六糖之间,无单糖的产生。在有保护剂存在的情况下,复合酶在室温下存放2个月其残余酶活均能超过85%。
In order to explore the optimal process of producing mannooligosaccharide by complex enzyme,konjac powder was hydrolyzed by recombinant β-mannase（ re Au Man5AN3C3） with high thermostability and different units of the recombinant β-endoglucanase（ re Au Cel12A） with high activity in this study based on synergistic hydrolysis of konjac powder with β-mannase and β-endoglucanase. Through the research on the factors of proportion of the two enzymes,hydrolysis p H value,hydrolysis time,hydrolysis temperature and substrate concentration,the optimum proportion and reaction conditions were determined. Also,the effects of preservatives on the stability of complex enzyme were studied. The results showed that the optimal process condition for producing mannooligosaccharide by complex enzyme was as follows： 30 g / L konjac gum was hydrolyzed by re Au Man5AN3C3 and re Au Cel12 A with proportion of 1∶1. 5（ former was 60 U / g for konjac powder） at 60 ℃ for 6 h. The hydrolysis rate could reach 65% under these conditions. The results from thin layer chromatography analysis showed that hydrolyzates of konjak gum mainly were oligosaccharides larger than biose,which were between biose and hexose. There was no monosaccharide. In the case of presence of preservative,the residual activities of complex enzyme were both above 85% after storage at room temperature for two months. This study provided a theoretical foundation for the industrial production of mannooligosaccharide by enzymatic method.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2015年第8期105-110,共6页
Food and Fermentation Industries
基金
河南省高等学校重点科研项目计划(15A416008)
南阳师范学院专项项目(ZX2015016)
