Fig. 3
(A-C) Calibration and (D-F) prediction of the PLS models for three offline parameters of H. polymorpha RB11 pC9-FMD (PFMD-GFP) cultivations at different potassium (K+) concentrations. This figure is based on the data from Additional file 1: Fig. S5. The PLS models were calibrated with the linearly interpolated values of the filled symbols and a total of 356 2D spectra of the two cultivation conditions shown in A-C. The PLS models for (A, D) glycerol, (B, E) CDW, and (C, F) pH value were generated using four, three, and three LVs. Solid and dotted lines describe the calculated parameter progression of duplicates. The hollow symbols were used for model validation only. The crossed symbols describe the value for the last offline sample taken after 54 h. Cultivation conditions: 48-well microtiter plate with round geometry, modified SYN6-MES medium, liquid volume = 800 μL, shaking diameter = 3 mm, shaking frequency = 1000 rpm, temperature = 30 °C