Fig. 2
From: Improving ethanol productivity through self-cycling fermentation of yeast: a proof of concept
Cycling fermentation experiments. OD600 (a), pH (b), glucose concentration (c), and ethanol content (d) were monitored through five cycles over a 47-h period. The cycle numbers are indicated with roman numerals. Error bars represent standard deviation of triplicate experiments, except for the OD600 value at 40.9 h in a (the end of cycle 4), which shows the result of duplicate samples (see “Methods”). Means that do not share the same letter are statistically different (95% confidence level, Tukey)