Fig. 2

Effect of different CO₂ concentrations on offline data of P. vulgatus shake flask cultivations. These data refer to the experiment shown in Fig. 1. Offline data of (a) HPLC analysis of produced organic acids, including formate, succinate, acetate and lactate and remaining glucose from four biological replicates with standard deviation. (b) Carbon balance in % as function of the CO₂ concentration in the gas supply. The start of the fermentation was set to 100%. No carbon balance is calculated for 10.0 and 15.0 vol% CO₂, as CO₂ could not be measured in this range. Initial samples were drawn after inoculation. (c) Final OD_600nm and final pH from four biological replicates with standard deviation. Experimental setup is illustrated in Fig. 5a. Medium: DMM-G, c_Glucose = 6 g L^− 1, c_buffer = 50 mM MOPS, T = 37 °C, n = 100 rpm, V_L = 50 mL, initial OD_600nm = 0.2, initial pH after inoculation = 6.9–7.15, vvm = 0.2 min^− 1, different gas mixtures of CO₂ in N₂, as indicated in legend