摘要:乙醛脱氢酶是一系类氧化各式各样脂肪族醛、芳香族醛为相应酸的酶,参与人体代谢的关键酶之一,它的主要作用是将乙醛氧化成乙酸,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。
本实验通过NADP+的紫外吸收确定了酶活。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酿酒酵母中提取乙醛脱氢酶。以正交实验得到了乙醛脱氢酶的最佳发酵条件是在180r/min下,28℃,培养18h。通过单因素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时。20458
关键词:乙醛脱氢酶;酿酒酵母;紫外色谱
Aldehyde dehydrogenase extraction technology research
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 毕业论文目录
1 绪论 1
1.1 乙醛脱氢酶的概述 1
1.2 乙醛脱氢酶在医学上的应用 1
1.2.1 乙醛脱氢酶与肿瘤 1
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 2
1.2.5 乙醛脱氢酶于白血病 2
1.3 乙醛脱氢酶在生物工程研究方面的应用 2
1.4 乙醛脱氢酶的研究进展 3
1.5 乙醛脱氢酶分离现状 3
1.5.1 盐析沉淀法 4
1.5.2 凝胶层析法 4
1.5.3 亲和层析法 4
1.5.4 有机溶剂沉淀法 4
1.5.5 双水相萃取法 5
1.6 本课题的研究目的和意义 5
2 实验材料和方法 6
2.1 实验试剂及仪器 6
2.2 实验方法 7
2.2.1 培养基和培养条件 7
2.2.2 乙醛脱氢酶活性的检测 7
2.2.3 蛋白浓度的检测 7
2.2.4 ALDH的纯化 8
2.2.5 液相色谱 8
2.2.6不同因素对酶的影响 10
3 实验结果与讨论 11
3.1 乙醛脱氢酶的最适发酵条件 11
3.2 蛋白质标准曲线 12
3.3 乙醛脱氢酶的活性测定 12
3.4 不同因素对乙醛脱氢酶的影响 13
3.4.1 提取液pH对ALDH提取的影响 13