State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing, People's Republic of China.
Appl Microbiol Biotechnol. 2010 Aug;87(5):1649-56. doi: 10.1007/s00253-010-2639-7. Epub 2010 May 6.
The effect of aeration on the performance of docosahexaenoic acid (DHA) production by Schizochytrium sp. was investigated in a 1,500-L bioreactor using fed-batch fermentation. Six parameters, including specific growth rate, specific glucose consumption rate, specific lipid accumulation rate, cell yield coefficient, lipid yield coefficient, and DHA yield coefficient, were used to understand the relationship between aeration and the fermentation characteristics. Based on the information obtained from the parameters, a stepwise aeration control strategy was proposed. The aeration rate was controlled at 0.4 volume of air per volume of liquid per minute (vvm) for the first 24 h, then shifted to 0.6 vvm until 96 h, and then switched back to 0.4 vvm until the end of the fermentation. High cell density (71 g/L), high lipid content (35.75 g/L), and high DHA percentage (48.95%) were achieved by using this strategy, and DHA productivity reached 119 mg/L h, which was 11.21% over the best results obtained by constant aeration rate.
在 1500-L 生物反应器中，通过分批补料发酵研究了通气对裂殖壶菌生产二十二碳六烯酸（DHA）的性能的影响。使用六个参数（比生长速率、比葡萄糖消耗速率、比脂质积累速率、细胞产率系数、脂质产率系数和 DHA 产率系数）来了解通气与发酵特性之间的关系。基于从参数中获得的信息，提出了逐步通气控制策略。在最初的 24 小时内，通气率控制在 0.4 体积空气/体积液体/分钟（vvm），然后在 96 小时之前切换到 0.6 vvm，然后在发酵结束前切换回 0.4 vvm。通过使用该策略，实现了高细胞密度（71 g/L）、高脂质含量（35.75 g/L）和高 DHA 百分比（48.95%），DHA 生产力达到 119 mg/L h，比恒定通气率获得的最佳结果提高了 11.21%。
