负载率和pH对上游无氧过反应堆中的甘油发酵和微生物群体的影响
Cândida N Cordeiro1,2, Patricia Rojas3, Shyrlane T S Veras4
1Department of Molecular Biology, Autonomous University of Madrid, 28049, Madrid, Spain. candida.cordeiro@estudiante.uam.es.
Bioprocess and biosystems engineering
|May 31, 2024
概括
在使用管的反应器中,用糖发酵实现了90%的糖消耗,主要产生1,3-propanediol (1,3-PDO). 一年后,细菌群落转向有利于1,3-PDO生产者,如Lacrimispora和Clostridium.
科学领域:
- 生物技术是生物技术.
- 微生物发酵 微生物发酵
- 生物反应器工程 生物反应器工程
背景情况:
- 甘油是生物柴油生产的副产品,为价值化提供了机会.
- 有效的微生物转化糖到有价值的产品,如1,3-propanediol (1,3-PDO) 对于可持续的化学生产至关重要.
研究的目的:
- 在反应堆中使用管作为支介质来研究糖醇发酵.
- 评估糖醇加载率 (gly-LR) 和二碳酸 (NaHCO3) 剂量对发酵性能的影响.
- 分析长期甘发酵期间细菌群体组成的变化.
主要方法:
- 一个使用管作为支介质的反应器被分为三个阶段运行,具有不同的甘油加载率和NaHCO3剂量.
- 在一年内监测了糖的消耗,最终产品的形成 (1,3-PDO,乙醇) 和细菌群体的动态.
主要成果:
- 在实验条件下,糖的消耗量达到约90%.
- 主要最终产品是0.40mol/mol-gly的1,3-propanediol (1,3-PDO),在pH>8和低gly-LR时观察到乙醇的产生.
- 长期运营导致了细菌群体的显著转变,1,3-PDO生产者 (Lacrimispora,Clostridium) 成为主导.
结论:
- 管有效地支持糖发酵,实现高糖转化.
- 优化条件,包括控制pH和NaHCO3剂量,可以提高1,3-PDO的产量.
- 持续的糖发酵促进了专门的1,3-PDO生产细菌的优势,表明生物产品生成的稳定微生物联盟.
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