基于发酵动力学模型的小球藻高密度发酵培养

High Cell Density Fermentation of Chlorella Based on Kinetics Model

构建了50 L发酵罐小球藻分批培养动力学模型,采用补料策略高密度发酵培养小球藻,考察了补料发酵过程中碳源的利用情况,采用实时荧光定量PCR技术分析了蛋白质合成关键酶二氨基庚二酸异构酶（dap F）、柠檬酸合成酶（CS）和葡萄糖-6-磷酸脱氢酶（G6PDH）的基因表达情况.结果表明,小球藻经补料培养120 h,细胞生物量达106.65 g/L,平均生长速率为0.89 g/（L·h）,葡萄糖的细胞得率为0.56 g/g,发酵过程中葡萄糖和尿素浓度对小球藻的dsp F,CS和G6PDH基因表达量有重要影响.

The kinetic model of batch fermentation of Chlorella sp. MBFJNU-17 in a 50 L fermenter was built, fed-batch strategy for high cell density cultivation was established. The application of carbon source was investigated. Furthermore, real-time quantitative PCR was used to determine the gene expression levels of key metabolic enzymes such as diaminopimelate isomerase（dap F）, citrate synthase（CS） and glucose-6-phosphate dehydrogenase（G6 PDH） in fed-batch fermentation. The results showed that the cell dry weight of Chlorella sp. MBFJNU-17 was 106.65 g/L, the average growth rate was 0.89 g/（L·h） and the yield of cell dry weight on glucose was 0.56 g/g, respectively, after fed-batch culture for 120 h. The gene expression levels of dap F, G6 DPH and CS of Chlorella sp. MBFJNU-17 were strongly related with the concentrations of glucose and urea during the fermentation.