Ughetti Manuel, Jussen Daniel, Riedlberger Peter
Research Group Chemical Engineering Institute of Chemistry and Biotechnology Zurich University of Applied Sciences Wädenswil Switzerland.
Buss ChemTech AG Pratteln Switzerland.
Eng Life Sci. 2018 Feb 22;18(5):281-286. doi: 10.1002/elsc.201700141. eCollection 2018 May.
Ejector loop reactors (ELR) are successfully used in industrial chemical processes for gas/liquid reactions. They achieve higher mass transfer rates compared to the stirred-tank reactor (STR) at comparable specific power input. Insufficient oxygen transport and shear stress induced growth inhibition are limiting parameters during microbial fermentation. Due to its better mass transfer characteristics, the ELR was expected to have beneficial effects on biomass and recombinant protein production. One concern, however, was whether the ELR's shear stress characteristics would have a negative effect. This study evaluated the suitability of using the Buss-Loop® Reactor (BLR), one of the most advanced ELR technologies, as a bioreactor. The well-studied STR was used as a reference. A lab scale BLR was adapted for microbial fermentation. Mass transfer rates and specific power inputs were within the same order of magnitude in the ELR and the reference STR. Maximum values of 207 and 205 h at power inputs of 6.9 and 9.7 W/L were measured in the ELR and STR, respectively. During batch fermentation of K12 MG1655, maximum cell densities were higher in the ELR (OD600 of 22) than in the STR (OD600 of 18). Green fluorescence protein (GFP) production with pGS1 was comparable; however, more GFP was released into the media in the ELR. This indicates higher cell disruption compared to the STR. Despite this drawback of the first prototype, our work clearly demonstrates the potential of the ELR as a system for microbial fermentations.
喷射环流反应器（ELR）已成功应用于工业化学过程中的气/液反应。在可比的特定功率输入下，与搅拌釜反应器（STR）相比，它们实现了更高的传质速率。在微生物发酵过程中，氧气传输不足和剪切应力诱导的生长抑制是限制参数。由于其更好的传质特性，预计ELR对生物质和重组蛋白生产具有有益影响。然而，一个担忧是ELR的剪切应力特性是否会产生负面影响。本研究评估了使用最先进的ELR技术之一的布斯环流®反应器（BLR）作为生物反应器的适用性。经过充分研究的STR用作参考。一个实验室规模的BLR被改装用于微生物发酵。ELR和参考STR中的传质速率和特定功率输入在同一数量级内。在ELR和STR中，分别在功率输入为6.9和9.7W/L时测得的最大值为207和205 h。在K12 MG1655的分批发酵过程中，ELR中的最大细胞密度（OD600为22）高于STR（OD600为18）。用pGS1生产绿色荧光蛋白（GFP）的情况相当；然而，ELR中有更多的GFP释放到培养基中。这表明与STR相比细胞破碎程度更高。尽管第一个原型存在这个缺点，但我们的工作清楚地证明了ELR作为微生物发酵系统的潜力。
