摘要
采用酪蛋白平板对藏香型白酒大曲中高产蛋白酶菌株进行分离筛选,然后通过硫酸铵沉淀、透析和DEAE-Sepharose FF阴离子交换层析对其产生的蛋白酶进行纯化,并研究其酶学性质。结果表明:菌株ZP-8产酶活力最高,为197.6 U/mL,经鉴定为地衣芽孢杆菌(Bacillus licheniformis)。纯化后测得酶的分子量约为45.43 kDa,最适pH值为8.0,在pH 7.0~11.0的范围内稳定性好,属于碱性蛋白酶。该酶最适反应温度为50℃,在30~50℃范围内稳定性较好;Mg^(2^(+))、Na^(+)、Ca^(2^(+))和Fe^(2^(+))对蛋白酶相对酶活力无显著影响(P>0.05),Cu^(2^(+))和Mn^(2^(+))具有显著的激活作用(P<0.05)。本研究对酒曲中产蛋白酶微生物的开发利用具有重要的参考价值。
In the experiment,the casein plate was used to isolate and screen the high-protease-producing strains from Tibetan-flavor liquor Daqu.Then,ammonium sulfate precipitation,dialysis desalting and DEAE-Sepharose FF anion exchange chromatography were used to purify the protease,and its enzymatic properties were studied.The results showed that strain ZP-8 had the highest enzyme activity of 197.6 U/mL,which was identified as Bacillus licheniformis.The molecular weight of the purified enzyme is about 45.43 kDa.The optimal pH of this enzyme is 8.0,and it is relatively stable in the pH rang of 7.0~11.0,which belongs to alkaline protease.The optimal temperature of this enzyme is 50℃,and it is relatively stable at 30~50℃;Mg^(2^(+)),Na^(+),Ca^(2^(+))and Fe^(2^(+))have no significant effect on the relative activity of protease(P>0.05),while Cu^(2^(+))and Mn^(2^(+))have remarkable activation effects(P<0.05).This research has important reference value for the development and utilization of protease-producing microorganisms.
作者
张红
张卫兵
乔海军
朱建宁
温得林
张智良
赵丽红
ZHANG Hong;ZHANG Weibing;QIAO Haijun;ZHU Jianning;WEN Delin;ZHANG Zhiliang;ZHAO Lihong(College of Food Science and Engineering,Gansu Agricultural University,Lanzhou Gansu 730070,China;College of Science,Gansu Agricultural University,Lanzhou Gansu 730070,China;Review Certification Center of Gansu Drug Administration,Lanzhou Gansu 730070,China;Gansu Tianzhu Tibetan Liquor Co.,Ltd.,Wuwei Gansu 733200,China)
出处
《食品与发酵科技》
CAS
2022年第4期8-13,共6页
Food and Fermentation Science & Technology
基金
国家自然科学基金地区科学基金项目(31960486)。
关键词
藏曲
筛选鉴定
蛋白酶
分离纯化
酶学性质
Zangqu
screening and identification
protease
separation and purification
enzymatic properties