Development of Integrated Lactic Acid Total Fermentation Processes

在本研究项目中，我们开发了一套完整的乳酸发酵系统，它包括细胞循环发酵系统和下游分离工艺。结合该系统，我们还对其他相关研究课题进行了研究，即：(1)开发了陶瓷膜高密度培养系统，可获得183g干重/L的高细胞存活率。(2)开发了由细胞循环系统和分离过程组成的一体化发酵系统。在分离过程中，我们考虑采用以阿拉明336为萃取剂(以油醇为溶剂)的萃取法。确定发酵和提取的pH值(4.2-4.5)对整个体系的优化非常重要，此外，我们还考虑使用离子交换树脂作为分离单元。(3)建立了葡萄糖和乳酸的在线检测集成传感器系统。(4)研究了在线优化控制系统。(5)研究了长杆菌和弗氏假单胞菌混合培养系统，研究了该反应器的新活性。(6)对微生物的呼吸链和能量产率进行了研究。

In the present research project, we developed an integrated lactic acid fermentation system which contains cell recycle fermentation system and the down-stream separation processes. In association with this system, we also investigated the related other research topics, Namely :(1) High cell density culture system was developed with ceramic membrane, and 183 g-dry cell weight/L could be attained with high cell viability.(2) The integrated fermentation system was developed which contains cell-recycle system and separation process. As the separation process, we considered to use extraction process using Alamin 336 as an extractant (oleyl alcohol was used as the solvent). It was shown to be quite important to find the pH values (4.2-4.5) for fermentation and extraction for the optimisation of total system.Furthermore, we considered to use ion-exchange resin as the separation unit. It was shown that high cell density culture with high substrate yield could be attained with this system.(3) An integrated on-line sensor system was developed to measure glucose and lactate on-line.(4) On-line optimising control system was investigated.(5) Mixed culture system using B.longum and P.freudenreichii was investigated to study the new activity of the reactor.(6) Respiratory chain and the energy yield were investigated for microorganisms.