Fig. 1
Fed-Batch fermentation of Komagataella phaffii BG11 strain with 40 g/L glucose in initial batch phase and DOT controlled > 30% performed in a 2 L stirred tank reactor. After 30 h (second vertical dotted line) induction is performed by methanol addition. In (A) the oxygen transfer rate (OTR), carbon dioxide transfer rate (CTR) and respiratory quotient (RQ) are depicted over time. In (B) the dissolved oxygen tension (DOT), cell dry weight (CDW) and pH are depicted over time. In (C) the glucose, ethanol and methanol concentrations are depicted over time. Cultivation was performed with 40 g/L initial glucose concentration. The start of feeding is marked by the first vertical dotted line. The feeding solution consisted of 640 g/L glucose. Induction by adding 1 vol% MeOH. 7 vol% MeOH was added to the feeding solution F2 after induction. Feeding rate F1 = 11 mL/h *exp(0.2 h−1 * t) from 25–30 h. Feeding rate F2 = 7 mL/h *exp(0.05 h−1 * t) from 30–54 h. The pH was controlled at 6