摘 要：花生四烯酸是一种ω-6系列长链多不饱和脂肪酸，具有重要的生物活性和营养作用。其传统来源有限且提取率低提取成本较高，导致其不能满足市场需求。微生物发酵法是制备花生四烯酸的新途径，此方法的核心问题是高产菌株的筛选。本论文以产花生四烯酸的高山被孢霉为出发菌株，采用硫酸二乙酯进行诱变，利用TTC染色法和气相色谱分析法分别进行初筛和复筛，最终获得了一株花生四烯酸高产菌株DES-25-4，其油脂得率可达到199 mg/g干菌体，比原始菌株提高了13.35%；其花生四烯酸含量达到11.26%，比原始菌株提高了9.52%；遗传稳定学实验表明，DES-25-4遗传稳定。本论文的研究可为花生四烯酸的生产提供菌株的选择。65906

毕业论文关键词：花生四烯酸，高山被孢霉，硫酸二乙酯诱变

Abstract：Arachidonic acid (AA) is a kind of long-chain polyunsaturated fatty acids of ω-6. It has an important role in biological activity. But the traditional source is limited and it costs too much to extract from them. Microbial fermentation is a new way to produce AA. The key is to screen high-yield strains in microbial fermentation. The aim of the experiment is to screen high-yield strains. In the experiment, Mortierella alpina producing AA was mutated by diethyl sulfate to improve the yield of producing AA. After screening repeatedly, a mutant DES-25-4 with high yield of lipid and AA was obtained. Comparing with the original strain, the yield of lipid increased by 13.35%, and the AA yield increased by 9.52%. Strain DES-25-4 had a good hereditary stability after several generations.

Keyword:  Arachidonic acid, Mortierella alpina, Mutation by diethyl sulfate

目   录

1 前言 4

2 材料与方法 8

2.1 实验材料 8

2.2 实验方法 9

2.2.1 菌种保藏方法 9

2.2.2 菌种活化方法 9

2.2.3 硫酸二乙酯（DES）诱变方法 9

2.2.4 初筛方法 9

2.2.5 红四氮唑染色法（TTC）检测花生四烯酸含量方法 9

2.2.6 复筛方法 10

2.2.7 突变株遗传稳定性的测定方法 11

3 结果与分析 12

3.1 硫酸二乙酯诱变致死率结果 12

3.2 硫酸二乙酯诱变的初筛结果 12

3.3 硫酸二乙酯诱变的复筛结果 15

3.4 突变菌株的遗传稳定性结果 15

4. 结论与展望 17

4.1 结论 17

4.2 展望 17

参 考 文 献 18

致 谢 20 

1  前 言

1.1 花生四烯酸及高山被孢霉的简介