摘要
乙醇脱氢酶(ADH)是醋酸杆菌发酵生产醋酸的关键酶。以硫酸铵为沉淀剂,采用盐析法对醋酸杆菌中乙醇脱氢酶进行初步的分离纯化,并研究其酶学特性。结果表明:ADH比活力从粗酶液的0.201U/mg提高到0.460U/mg,纯化倍数为2.289;其最适作用pH值为7.5～8.0,pH值为7.8时酶活力达到最大,pH值为7.0时酶较为稳定;最适作用温度为35℃,温度为30℃～40℃时酶活力较为稳定,温度超过45℃后酶活力急剧下降。通过对乙醇底物浓度对ADH活力影响的研究,ADH对乙醇的米氏常数Km为2.59×10-2mol/L。
The alcohol dehydrogenase（ADH） is a key enzyme which catalyzes the formation of acetic acid from alcohol duringthe fermentation with acetic acid bacteria.ADH from Acetobacter sp.CCTCC M209061 was primarily separated and purified by the salting out method with ammonium sulfate as precipitant,and its properties were studied.The results showed that the ADH activity was improved from 0.201 U/mg of crude enzyme liquid to 0.460 U/mg and purified multiplier was 2.289,the maximum activity of ADH was obtained at pH value 7.8 and 35 ℃,and it was quite stable at pH value 7.0 and at 30 ℃～40 ℃.But its enzymatic activity sharply declined when the temperature was over 45 ℃.The Km constant of ADH based on the substrata of alcohol was 2.59×10-2 mol/L by investgating the effect of alcohol concentrationon enzyme activity of ADH.
出处
《食品研究与开发》
CAS
北大核心
2010年第9期170-173,共4页
Food Research and Development
基金
广东省科技攻关项目(项目编号:2009B020312017)
韶关市科技项目(项目编号:韶科[2009]80)
