Fig. 6
Production of dicarboxylic acids by fermentation of the SSL in bioreactors. a Consumption of the carbon sources present in the SSL and biomass formation by the engineered XylC2 6_4 MA strain. b Production of dicarboxylic acids from the SSL at pH = 4.5. Due to the different length of the lag phase and subsequent time shift between the parallel bioreactors, a representative bioreactor experiment was chosen and is displayed. Two particular stages of the experiment characterized by consumption of hexoses, acetic acid and production of succinic acid (STAGE I), and xylose consumption and malic acid production (STAGE 2) are indicated. The data for the parallel bioreactor experiment is given in Additional file 2: Fig. S5. c Yields of dicarboxylic acids in mol of the formed product per mol of the carbon sources consumed. The yields are given for each stage as well as a sum of the both stages, i.e., endpoint titer of the product per total amount of consumed carbon. For succinic acid that is re-consumed during the second stage, the highest titer was taken for the yield calculation. The values are averages of both bioreactor experiments with standard deviation (N = 2)