β-甘露聚糖酶产生菌的筛选及酶学性质研究  

Screening of Strains Producing β-mannanase and its Enzymatic Properties

作　　者：武志芳[1] 张霞[1] 张胜潮[1] 张杰[1] 胡承[1] 

机构地区：[1]四川大学生命科学学院生物资源与生态环境教育部重点实验室,四川成都610064

出　　处：《时珍国医国药》2011年第10期2515-2517,共3页Lishizhen Medicine and Materia Medica Research

基　　金：国家"十一五"科技支撑计划项目(No.2007BAC18B03)

摘　　要：目的筛选产β-甘露聚糖酶的优良菌株,对其进行分类鉴定及酶学特性的研究,并对菌株产生的β-甘露聚糖酶水解魔芋精粉的产物进行分析。方法采用平板划线及摇瓶复筛的方法筛选β-甘露聚糖酶产生菌,通过在Genebank中比对菌株的16SrDNA序列进行鉴定。按照NDS法、单因子试验初步研究该酶的酶活力和酶学性质;利用薄层层析对该酶降解魔芋精粉的产物进行分析。结果筛选到2株β-甘露聚糖酶产生菌E1、B2,分别鉴定为阴沟肠杆菌属、芽孢杆菌属,酶活力分别为11.84～9.98U/ml。B2菌株产生的β-甘露聚糖酶最适温度是50℃,最适pH是6.0;该酶在30～60℃、pH6.0～7.0条件下较稳定;Fe2+,Mn2+对其有促进作用,EDTA,Zn2+,Cu2+对其有较强的抑制作用。薄层层析分析原始发酵液与浓缩发酵液显示,浓缩过程中β-甘露聚糖酶继续作用于魔芋精粉和聚合较大的葡甘露寡糖,最终产物主要是聚合度较小的葡甘露聚糖。结论 B2菌株产生的β-甘露聚糖酶具有良好的酶学性质,且降解魔芋精粉的产物主要是聚合度较小的葡甘露聚糖,在工业上有很好的应用前景。ObjectiveTo separate and identify strains producing β-mannanase from rhizosphere loam of a wild plantain tree in Pingwu,then to study enzymatic characteristics of β-mannanase,and analyze products of β-mannanase hydrolysising Konjac. MethodsThe strains was identified by 16S rDNA BLAST in the genebank;their enzymatic activity was evaluated according to DNS and single factor analysis method.Through thin-layer chromatography,products of β-mannanase hydrolysising Konjac was analyzed. ResultsB1,E2 were identified as Enterobater clocae,Bacilus by 16S rDNA respectively.Their enzymatic activities were 11.84 U/ml and 29.98 U/ml.The optimal conditions of β-mannanase produced by B2 were 50℃ and pH6.0.Under the conditions of 30~60℃ and pH6.0~7.0,the enzymatic activity was stable.Furthermore,Fe2＋,Mn2＋ had the enhancement effect and EDTA,Zn2＋ and Cu2＋ could strongly inhibit the enzymatic activity.Analyzing original and concentrated zymotic fluid through thin-layer chromatography（TLC）,β-mannanase could hrdrolyze konjac and mannan oligosaccharides with high degree of polymerization,the final products were mainly Konjac glucomanna. Conclusionβ-mannanase produced by B2 has excellent enzymatic characteristics,the products of hydrolysising Konjac are mainly Konjac gluconmanna,so β-mannanase produced by B2 will have the potential for mass production.

关 键 词：Β-甘露聚糖酶 分离 鉴定 魔芋葡甘露低聚糖 薄层层析 

分 类 号：R283[医药卫生—中药学]