摘要:达托霉素是一种新型环脂肽抗生素,在体外对革兰氏阳性菌具有显著地抑制作用,包括对多种药物产生耐药性的革兰氏阳性菌。目前,鉴于临床上广泛使用的万古霉素等抗生素的耐药性问题的突出,所以提高达托霉素产量迫在眉睫。故本论文对达托霉素发酵条件优化进行探讨,获得了最优发酵条件:接种量 5%,最佳碳源 2.2%葡萄糖,最佳氮源 2.5%黄豆粉,前体癸酸添加量为0.15g/L。在该发酵条件下,达托霉素效价达到538.0mg/L,较未优化前(446.1mg/L)提高了20.6%。56789
毕业论文关键词:达托霉素;玫瑰孢链霉菌;发酵;优化
Abstract:Daptomycin is a novel cyclic lipopeptide antibiotic that has a significant inhibitory effect on Gram-positive bacteria, including those that are resistant to multiple drugs. Nowadays, owing to the widespread used antibiotics clinically, such as vancomycin,are facing the serious problem of tolerance, it is necessary to improve the output of daptomycin. Daptomycin is the secondary metabolite of Streptomyces roseosporus. Because the production is toxic and inhibited the microorganism itself, which causes the output of daptomycin is still insufficient and unstable. Therefore, this paper will discuss optimization of fermentation conditions for daptomycin. The optimal fermentation conditions are as follows: inoculation amount 5%, the best carbon source glucose 2.2%, the best nitrogen source soybean flour 2.5%, the precursor decanoic acid amount 0.15g/L. Under the mentioned optimal fermentation conditions,the titer of daptomycin is up to 538.0mg/L, which increases 20.6% in the basis of primary fermentation conditions(446.1mg/L).
Keywords:Daptomycin; Streptomyces roseosporus ; Fermentation; Optimization
目录
1. 绪论 5
1.1 达托霉素 5
1.1.1 达托霉素的简介 5
1.1.2 达托霉素的抗菌活性 5
1.1.3 达托霉素的临床应用 6
1.1.4 达托霉素的作用机制 6
1.2 达托霉素的发酵生产 7
1.2.1 发酵温度对达托霉素发酵的影响 7
1.2.2 发酵pH对达托霉素发酵的影响 7
1.2.3 碳源对达托霉素发酵的影响 7
1.2.4 氮源对达托霉素发酵的影响 8
1.2.5 前体流加对达托霉素生成的影响 8
1.3 达托霉素含量的检测 8
1.3.1 托霉素的生物检测 8
1.3.2 达托霉素的HPLC检测法 9
1.4 课题立意 9
1.4.1 研究目的与意义 9
1.4.2 研究内容 9
2 材料与方法 10
2.1 实验仪器与试剂 10
2.1.1 实验仪器 10
2.1.2 实验试剂 10
2.2 实验用菌种 11
2.3 实验用培养基 11
2.4 实验方法 12
2.4.1 菌种的保藏方法 12
2.4.2 菌种的活化 12
2.4.3 种子的培养方法