变幻青霉氨基甲酸乙酯降解酶产酶条件优化及酶的底物特异性  

Optimization of Fermentation Conditions of P.variabile JN-A525 and Substrate Specificity of Urethanase

作　　者：谷晓蕾[1] 田亚平[1] 

机构地区：[1]江南大学工业生物技术教育部重点实验室,江苏无锡214122

出　　处：《食品与生物技术学报》2013年第6期603-607,共5页Journal of Food Science and Biotechnology

基　　金：国家973计划项目(2012CB720802)

摘　　要：在单因素优化基础上,运用正交试验设计理论,优化氨基甲酸乙酯降解酶产生菌P.variabile JN-A525的产酶条件。优化发酵培养基配方为:葡萄糖20 g/L,牛肉膏10 g/L,KH2PO45g/L、NaCl 1 g/L、KCl 5 g/L;发酵条件为:初始pH 6.0、培养温度32℃、接种体积分数3%、250 mL摇瓶装量70 mL、摇床转速100 r/min,在此优化条件下酶活比优化前提高了3.47倍。对经超声破碎、(Na)2SO4盐析、Superdex G-75凝胶过滤层析步骤初步纯化的酶之底物特异性的研究表明,在模拟黄酒体系下,该酶对尿素和氨基甲酸乙酯有相对强的降解作用,对一些酯类和氨基酸没有降解作用。The fermentation process for P.variabile JN-A525 was optimized by single factor experiment and orthogonal tests. The results showed that the medium was composed of glucose 20 g/L,beef extract 10 g/L,KH2PO4 5 g/L,NaCl 1 g/L and KC1 5 g/L. The optimum fermentation conditions was 32 ℃,inoculum volume 3% ,the optimum amount in flask 70/250 mL and the rotation speed of 100 r/min. Under these optimal conditions,the highest urethanase activity is 3.47 fold more than that of previous cinditions. After sonieation methods, sodium-sulfate salting-out and superdex G-75 gel filtration chromatography,the urethanase from Penicillium variabile JN-A525 is further determined substrate specificity. Under simulated conditions ,the urethanase has a relatively strong catalytic activity to urea and EC. Meanwhile,urethanase cannot catalyze the decomposition of amino acids and esters.

关 键 词：氨基甲酸乙酯降解酶 优化 纯化 底物特异性 

分 类 号：TQ925[轻工技术与工程—发酵工程]