摘要
以新鲜牛奶作为研究对象,利用分光光度计,基于底物浓度、温度和pH值研究以乙醛为底物的乙醛脱氢酶动力学系统。结果表明,牛奶中的醛脱氢酶酶促反应动力学符合米氏方程所描述的单底物酶促反应动力学,相应的动力学参数Km=0.0063mol/L,Vmax=0.036U/min。此外,醛脱氢酶不是耐热酶,它的最适温度在35℃左右,最适pH在7.0左右,底物浓度与酶活力的关系基本符合酶促反应动力学。同时研究了10种试剂对醛脱氢酶的抑制或激活作用,硝酸钙和硫脲是比较理想的抑制剂,硝酸钾和钼酸铵则是比较理想的激活剂。
On the substrate concentration, temperature and pH, the acetaldehyde dehydrogenase Based kinetics in fresh milk was investigated by a spectrophotometer with aldehyde being substrate. The results showed that the acetaldehyde dehydrogenase kinetics was consistent with the enzyme kinetics of a single substrate described by Michaelis-Menten. Its parameters Km is 0.006 3 mol/L and Vmax is 0.036 U/min. In addition, the enzyme is not heat-resistant. Its optimum temperature and pH is around 35 ℃ and 7.0, respectively. Overall, the relationship between the substrate concentration and enzyme activity corresponds to the enzyme kinetics.At the same time have studied inhibition and activator acting to aldehyde dehydrogenase. Ca(NO3)2 and liuniao are ideal Inhibitor. KNO3 and ammonium molybdate are ideal Activator.
出处
《食品研究与开发》
CAS
北大核心
2009年第12期54-57,共4页
Food Research and Development
关键词
牛奶
醛脱氢酶
动力学
抑制剂
激活剂
milk
aldehyde dehydrogenase
kinetics
inhibitor
activator