Fig. 2

Product yields (mol/e-mol) obtained in each transfer for all enrichment conditions and final pH at the moment of the transfer. The columns show the values for the fermentation transferred and the error bars indicate the corresponding values of the duplicate experiment. Additional information on substrate consumption and apparent biomass yields can be found in Additional file 1: Figure S5. a Enrichment HT6 at an initial pH of 6; b enrichment HT5.5 at an initial pH of 5.5; c enrichment HT5.5YE at an initial pH of 5.5 with YE (0.5 g/l); d enrichment HT5YE at an initial pH of 5 with YE (0.5 g/l); e enrichment NT5YE at an initial pH of 5 with YE (0.5 g/l)