高细胞密度的合成气发酵:pH值和的部分压力如何影响连续发酵中的生产率和产品比率
Lukas Perret1, Nikolaos Boukis1, Jörg Sauer1
1Institute of Catalysis Research and Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen 76344, Baden-Wurttemberg, Germany.
Bioresource technology
|October 22, 2023
概括
连续合成气发酵实现了3000小时的稳定运行. 在pH值5.7和增加的部分压力下,确定了吸收和乙醇产量的最佳条件.
科学领域:
- 生物技术是生物技术.
- 化学工程是化学工程的重要组成部分.
- 微生物的新陈代谢
背景情况:
- 合成气发酵为生物燃料生产提供了一个可持续的途径.
- 优化连续发酵过程与细胞保留对于工业可行性至关重要.
- 了解微生物对不同过程参数的反应是提高产量的关键.
研究的目的:
- 为了研究连续合成气发酵与总细胞保留的长期稳定性和性能.
- 为了确定最佳的pH值和的部分压力,以最大限度地提高乙醇的生产和的吸收.
- 为了确定在合成气发酵过程中对微生物活动的限制和抑制作用.
主要方法:
- 使用*Clostridium ljungdahlii*进行连续合成气发酵,完全保留细胞.
- 在高压下 (高达4barg) 和长时间 (高达3000小时) 运行.
- 系统地改变pH值和的部分压力,以评估它们对发酵性能的影响.
主要成果:
- 在高达4巴克的压力下,稳定的连续发酵可以保持长达3000小时.
- 在pH 5.7时观察到最高的吸收和乙醇时空产量,超过pH 5.9.
- 增加的部分压力显著提高了的吸收率和乙醇的形成,达到10mmol L-1h-1的纪录产量野生类型的C. ljungdahlii*.
- 较低的pH值增加了酸与乙醇的比率,但没有影响C2的时空产量.
- 吸收在理论平衡度以上显著减少,这表明酶抑制.
结论:
- 连续合成气发酵与总细胞保留是一个稳定和可行的长期过程.
- 优化的pH (5.7) 和的部分压力对于最大限度地提高乙醇生产效率至关重要.
- 在高度下,吸收的酶性限制发生,这表明了代谢工程的潜在目标.
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