The process design proven for one fermentor system is not always directly transferrable to other system formats without adaptation. Hence, it is necessary to understand the interrelation between the physical features of a fermentor and how these features ultimately affect the performance of the system.
Here, we compare the performance of the XDR‑500 MO fermentor with the XDR‑50 MO system. A process for dAb production in E. coli, initially developed for a conventional stainless steel 20 L fermentor, was used as the model. The described process was scaled from a XDR‑50 MO fermentor culture, with a start volume of 30 L, to a larger XDR‑500 MO fermentor culture, with a start volume of 350 L. The process was adapted to, but not optimized for, the 50 and 500 L pair of single‑use fermentor systems.