摘要： 乙醛脱氢酶(Aldehyde Dehydrogenase，ALDH)是催化乙醛氧化为乙酸的反应的酶。是人体内代谢的关键酶之一。肝中的乙醛脱氢酶负责将乙醇氧化为乙醛，生成的乙醛在乙醛脱氢酶催化下转变为乙酸，最终分解为二氧化碳和水。从动物、植物体内能够分离得到乙醛脱氢酶，但其过程复杂、费用昂贵，并且提取量少。微生物有培养周期短、易于培养、繁殖快等优点，所以从微生物中提乙醛脱氢酶有很大的前景。58081

本实验研究了通过紫外分光光度法确定了酶活力。探索了利用细胞破碎、硫酸铵分级盐析以及DEAE-32阴离子交换层析等方法从从酵母培养液中提取乙醛脱氢酶。通过单因素及正交实验得到了乙醛脱氢酶的最适提取条件是pH7.5的缓冲液，料液比为1：3。

毕业论文关键词：乙醛脱氢酶；发酵条件；工艺优化

Study on extraction process of aldehyde dehydrogenase

Abstract:

Aldehyde dehydrogenase is a enzyme which can oxidize all kinds of  aliphatic  aldehyde and aromatic aldehydes. It mainly effort is to acetaldehyde oxidation into acetic acid. Finally it will be CO2 and water. It is different to separation aldehyde dehydrogenase from animals and plants. It is expensive and the process is complex. Despite all, the production is low. Microorganism has lots of advantages. Such as short training period, easy to cultivate and rapid propagating. So mention of acetaldehyde dehydrogenase from microorganisms have great prospects.

In this study, the enzyme activity was determined by the ultraviolet spectrophotometer. Cytosolic Aldehyde dehydrogenase was extracted from Brewers Yeast by using Ultrasonic crushing method , ammonium sulfate fractionation and ion exchange chromatography on DEAE-32, and the properties of ALDH were studied.  With the orthogonal experiment the optimum fermentation conditions of acetaldehyde dehydrogenase is 180r/min, 28℃ and 18h. By single factor experiment, the optimum extraction condition of ALDH is pH7.5, and the solid-liquid rate is 1:3.

Key words: Aldehyde dehydrogenase; yeast; ultraviolet spectrophotometer

1.绪论 1

1.1 乙醛脱氢酶的概述 1

1.1.1乙醛脱氢酶的分类 1

1.1.2 乙醛脱氢酶的结构 1

1.2乙醛脱氢酶与疾病的防治 2

1.2.1 乙醛脱氢酶与肿瘤 2

1.2.2 乙醛脱氢酶与心血管疾病 2

1.2.3 乙醛脱氢酶与神经系统 2

1.2.4乙醛脱氢酶与酒精中毒 3

1.2.5乙醛脱氢酶于白血病 3

1.3乙醛脱氢酶分离研究 3

1.4  乙醛脱氢酶的提纯研究 3

1.4.1 盐析沉淀法 4

1.4.2 凝胶层析法 5

1.4.3 亲和层析法 5

1.4.4 有机溶剂沉淀法 5

1.4.5 双水相萃取法 5

1.5本课题的研究目的意义和内容 5

2.实验材料和方法 7

2.1 实验试剂及仪器 7

2.2 实验方法 8

2.2.1 菌体培养及测定方法 8

2.2.2 NADH标准曲线绘制