【作者】 叶慧；

【导师】 万红贵；

【作者基本信息】 南京工业大学 ， 生物化工， 2006， 硕士

【摘要】 L-鸟氨酸是精氨酸合成中间体,对肝病治疗与心脏强健亦非常有效,其市场前景越来越广阔。本文以代谢控制发酵理论为指导,重点对L-鸟氨酸高产菌1006进行摇瓶培养条件、发酵条件的优化,并对其发酵动力学分别进行研究。主要研究内容结果如下:（1）利用HPLC-ELSD法测定发酵液中L-鸟氨酸。色谱条件为Prevail C18柱, 0.06% HFBA溶液-乙腈（88∶1 2）为流动相,柱温30℃,流速为0.8 mL/min,ELSD漂移管温度110℃,气体流量2.8 L/min。L-鸟氨酸在0.1-0.6mg/mL范围内,线性回归比非常显著（ R²= 0.9998）,平均回收率达到98.94 %。该法简便、快速、准确性高、重复性好,适合于L-鸟氨酸的定量分析。（2）研究菌株1006的摇瓶分批发酵条件。应用Box-Behnken designs和响应面法分别优化出种子培养基和发酵培养基的配比,优化后发酵培养基为（g/L）:葡萄糖80.50,酵母膏20.50,（NH4）2SO4 53,MgSO₄·7H₂O 3.70, K₂HPO₄·3H₂O 1.50, CaCO₃10,FeSO₄·7H₂O 18.30mg/ L,MnSO₄·H₂O22.38mg/L,Biotin0.05 mg/ L,VB10.1mg/ L。并对种子培养条件和发酵条件进行了研究,优化后摇瓶发酵培养条件为:发酵培养基初始pH 7.2;装液量30 mL/500mL三角瓶;摇瓶转速为200r/min;发酵温度为30℃。在优化条件下,1006菌株摇瓶分批发酵72h,产L-鸟氨酸33.59g/L。（3）对1006菌株进行了5L罐发酵研究,考察不同搅拌转速及不同恒定pH值对菌株1006产L-鸟氨酸分批式发酵的影响,确定了最佳搅拌转速500r/min与最适pH6.8,产率最高达36.04g/L。并对该条件下发酵过程进行动力学分析与研究,建立该菌株分批发酵的动力学模型。结果表明该组模型能够很好地拟合鸟氨酸发酵过程。更多还原

【Abstract】 L-ornithine is an intermediate metabolite in arginine biosynthesis. It is effective in the treatment of liver disorders and helps strengthen the heart. For these reasons, it has a sizable world market. According to the theory of metabolic control fermentation, the dissertation focuses on fermentation condition of L-ornithine producing strain1006 and how to control the fermentation process. The main research contents and results are as follows:（1） A method of HPLC-ELSD was established using Prevail C18 column for the determination of L-ornithine. The mobile phase was 0.06% HFBA in water- acetonitrile （88∶12） , with a flow rate of 0.8 mL/min at 30℃. The temperature of drift tube heater was 110℃and the gas was flowing at the rate of 2.8 L/min. A good linearity was obtained in the range of 0.1–0.6mg/mL （R²= 0.9998） for L-ornithine. The average recovery of L-ornithine was 98.94 %. The method is simple and rapid with reproducibility for the determination of L-ornithine in the fermentation broth.（2） The batch fermentation condition of strain1006 in shake flask was investigated. The proportions of seed medium and fermentation medium were optimized by Box-Behnken design experiment and central composite design with response surface analysis method. The optimum fermentation medium was as follow （g/L）: glucose 80.50, yeast extract 20.50, （NH₄）₂SO₄ 53,MgSO₄·7H₂O 3.70, K₂H PO₄·3H₂O 1.50,CaCO₃10,FeSO₄·7H₂O 18.30mg/L,MnSO₄·H₂O22.38mg/L,Biotin0.05 mg/L,VB10.1mg/L. The optimized fermentation condition was as follow: the initial pH value was 7.2, the fermentation medium size was 30mL in the flask of 500mL, the rotated speed of flask was 200r/min and the fermentation temperature was 30℃. Under the optimum condition, L-ornithine yield was up to 33.59g/L by strain1006 after fermentation for 72h by flask-shaking batch fermentation.（3） The L-ornithine batch fermentation process of strain1006 in 5-liter更多还原