高产酯化酶红曲霉的筛选、鉴定及其产酶条件优化  

Screening, identification and enzyme production conditions optimization of high-yield esterase Monascus

作　　者：朱俊颖 夏芊芊 甘晋铭 余登洋 丁保坤 陈茂彬[1] 张玉[1] ZHU Junying;XIA Qianqian;GAN Jinming;YU Dengyang;DING Baokun;CHEN Maobin;ZHANG Yu(School of Life and Health Sciences,Hubei University of Technology,Wuhan 430068,China;Hubei Aiheju Technology Co.,Ltd.,Huanggang 438300,China)

机构地区：[1]湖北工业大学生命科学与健康工程学院,湖北武汉430068 [2]湖北艾合菊科技有限责任公司,湖北黄冈438300

出　　处：《中国酿造》2024年第12期103-109,共7页China Brewing

基　　金：湖北省自然科学基金面上项目(2022CFB476)。

摘　　要：该研究采用传统培养分离法从大曲、红曲米、酒糟样品中分离红曲霉(Monascus)菌株,通过透明圈法及酯化酶活力测定从中筛选高产酯化酶菌株,并通过形态观察及分子生物学技术对其进行菌种鉴定。在发酵培养基优化的基础上,以酯化酶活力为响应值,采用单因素及响应面试验对其发酵条件进行优化,并对所产酯化酶底物特异性进行研究。结果表明,筛选得到一株高产酯化酶的红曲霉菌株XTQ,其酯化酶活力为(43.08±0.266)U/L。经鉴定,该菌株为紫色红曲霉(Monascus purpureus)。菌株XTQ产酯化酶最优液态培养基成分为葡萄糖50 g/L、牛肉浸粉20 g/L、硫酸镁1 g/L、磷酸二氢钠1 g/L;最优发酵条件为初始pH值6.0、发酵温度33.4℃、转速185 r/min。在最佳条件下,酯化酶活力达(93.82±5.65)U/L,是优化前的2.18倍。菌株XTQ所产酯化酶对己酸有良好的选择性,为合成己酸乙酯酯化酶的生产提供了参考。In this study,Monascus strains were isolated from Daqu,Hongqu rice and distillers'grains samples by traditional culture and separation method,and the high-yield esterase strain was screened by transparent circle method and esterase activity measurement and identified by morphologic observation and molecular biology techniques.On the basis of fermentation medium optimization,the fermentation conditions were optimized by single factor and response surface experiments using esterase activity as response value,and the substrate specificity of the esterase produced by the screened strain was investigated.The results showed that a high-yield esterase strain of Monascus XTQ was screened,with the esterase activity(43.08±0.266)U/L,which was identified as Monascus purpureus.The optimal esterase-producing liquid medium components for the strain XTQ were obtained as follows:glucose 50 g/L,beef extract 20 g/L,MgSO_(4)1 g/L,and NaH2SO_(4)1 g/L,and the optimal fermentation conditions were as follows:pH 6.0,fermentation temperature 33.4℃,and rotational speed 185 r/min.Under these optimal conditions,the activity of esterase was up to(93.82±5.65)U/L,which was 2.18 times of that before optimization.The esterase produced by the strain XTQ had good selectivity for hexanoic acid,which provided a reference for the production of synthetic ethyl hexanoate esterase.

关 键 词：红曲霉 酯化酶 筛选 鉴定 发酵条件 响应面法 底物特异性 

分 类 号：Q93-31[生物学—微生物学]