山西老陈醋高产糖化酶霉菌的筛选、鉴定及产酶条件优化  

Screening and identification of mold with high-yield saccharifying enzyme from Shanxi mature vinegar and optimization of enzyme production conditions

作　　者：王佳丽[1] 朗繁繁 陈旭峰 王如福[1] 许女[1] WANG Jiali;LANG Fanfan;CHEN Xufeng;WANG Rufu;XU Nv(College of Food Science and Engineering,Shanxi Agricultural University,Jinzhong 030801,China;Shanxi Zilin Vinegar Co.,Ltd.,Taiyuan 030400,China;Experimental Teaching Center,Shanxi Agricultural University,Jinzhong 030801,China)

机构地区：[1]山西农业大学食品科学与工程学院,山西晋中030801 [2]山西紫林醋业股份有限公司,山西太原030400 [3]山西农业大学实验教学中心,山西晋中030801

出　　处：《中国酿造》2019年第4期100-105,共6页China Brewing

基　　金：山西省应用基础研究项目(201701D221189);山西省科技重大专项项目(201703D211001-06-05)

摘　　要：从山西老陈醋大曲中共分离出75株霉菌,对高产糖化酶霉菌进行筛选、鉴定及产酶条件优化。结果表明,筛选出1株优良黑曲霉(Aspergillus niger)186,在麸皮固态培养基中其糖化酶、蛋白酶和纤维素酶酶活分别为3 963.79 U/g、368.80 U/g和4 476.60 U/g。糖化酶基因聚合酶链反应(PCR)测序结果显示,该酶脱氧核糖核酸(DNA)序列编码区长1 449 bp,共编码482个氨基酸,预测酶的分子质量为51.75 kDa,等电点为3.99。最佳产酶条件为:麸皮4%,硫酸铵0.5%,初始pH值为7.0,接种量8%,装液量100 m L/250 m L,转速145 r/min,培养7 d。在此优化条件下,黑曲霉186糖化酶活力可达892.98 U/m L,是优化前的1.77倍。75 mold strains were isolated from Shanxi mature vinegar Daqu,the molds with high-yield saccharifying enzyme were screened and identified,and the enzyme production conditions were optimized.The results showed that a dominate strain Aspergillus niger 186 was screened,and the activity of saccharifying enzyme,protease and cellulase in bran solid medium was 3 963.79 U/g,368.80 U/g,and 4 476.60 U/g,respectively.The sequencing result of polymerase chain reaction(PCR)of saccharifying enzyme gene showed that the sequences length of coding region for DNA of glycosylase gene was 1 449 bp,which encoded a total of 482 amino acids.The calculated molecular weight and isoelectric point of the enzyme were 51.75 kDa and pH 3.99,respectively.The optimal enzyme production conditions for the A.niger 186 were bran 4%,ammonium sulfate 0.5%,initial pH 7.0,inoculum 8%,liquid loading volume 100 ml/250 ml,rotation speed 145 r/min and fermentation time 7 d.Under the optimal conditions,the saccharifing enzyme activity could reach 892.98 U/ml,which was 1.77 times higher than that of before optimization.

关 键 词：山西老陈醋 霉菌 筛选 鉴定 糖化酶 条件优化 

分 类 号：TS201.3[轻工技术与工程—食品科学]