放射型根瘤菌WSH2601生产辅酶Q_(10)的摇瓶发酵条件

Coenzyme Q_(10) Shaking-flask Culture Conditions by Rhizobus radiobacterium WSH2601

以放射型根瘤菌 (Rhizobusradiobacterium ,WSH2 6 0 1)作为辅酶Q10 的生产菌株 ,研究了氮源、碳源、接种量、溶氧、初始 pH、发酵温度及添加物等因素对细胞生长与产物辅酶Q10 合成的影响 .结果表明 :玉米浆和酵母膏是较好的氮源 ,葡萄糖与蔗糖是辅酶Q10 发酵的较好的碳源 ,接种量对辅酶Q10 发酵的影响不大 ,为 4 % .适宜的初始 pH值为 7,番茄汁能较好地促进细胞的生长 ;添加玉米浆、L 甲硫氨酸、番茄汁和异戊醇有利于产辅酶Q10 ;溶氧对细胞生长与产物辅酶Q10 合成的影响较显著 .通过正交试验初步确定了发酵条件 :碳源为 1.5 g/dL葡萄糖和 2 .5 g/dL蔗糖混合物 ,酵母膏 0 .8g/dL ,初始pH 7,每 5 0 0mL装液量为 5 0mL .最后经综合优化条件 ,在摇瓶发酵条件下 :菌体生长量 (以干重计 )为 13.8g/L ,发酵液中辅酶Q10 产量达到 2 2 .7mg/L ,比优化前分别提高 34%和 5 3% .

Several factors influencing CoQ 10 production with Rhizobium radiobacter WSH2601 were investigated. The results showed that yeast extract and corn steep liquor are suitable nitrogen sources, and the carbon sources such as glucose and sucrose are favourate for cell growth and CoQ 10 accumulation. The inoculum size had no great effect on CoQ 10 fermentation. The optimum initial pH for CoQ 10 fermentation was 7.0. Dissolved oxygen was an important factor influencing the cell growth and the CoQ 10 fermentation. Tomato juice was favourate for the cell growth and addition of corn syrups, L methionine , isoprenol and tomato juice can enhance the CoQ 10 accumulation in the cells. The optimized combination of important fermentation conditions was carried out by orthogonal experiment: carbon sources of glucose 1.5%, sucrose 2.5%, and yeast extract 0.8%. Initial pH was 7 and the volume of medium (medium volume vs flask volume) was 50 mL/500 mL. Under the optimized shaking flask conditions, the biomass and the CoQ10 concentration reached 13.8 g/L and 22.7 mg/L, respectively, which were 34% and 53% higher than those under original conditions.