Fig. 1

Overview of different cultivation steps, cultivation systems, and measured online and offline data. Both, pre-culture and main culture, were performed in mineral medium E containing glycerol, glutamic acid, and citric acid as carbon sources. Pre-cultures were carried out in 500 mL shake flasks in a RAMOS (Respiration Activity MOnitoring System) device. The main culture was performed in 500 mL flasks in three cultivation systems in parallel: RAMOS device, power input shaker and separate 500 mL shake flasks. The RAMOS device allowed for an online measurement of the oxygen transfer rate (OTR) of the culture. The power input shaker contained a torque sensor for online determination of the volumetric power input which was used to calculate the online effective viscosity. Separate shake flasks were used for offline analysis