Figure 2.
Effect of the S. cerevisiae inoculum time and SF addition time on cellulase activity, DCWA, DCWS, and ethanol concentration in co-culture of A. cellulolyticus and S. cerevisiae. Co-culture was carried out using cellulase producing-medium containing 2.5 g/l of yeast extract in a shake flask with shaking at 220 rpm. Ethanol production was started by additions of 10% inoculum of S. cerevisiae and 50 g/l of steam-sterilized SF as a powder at the culture time of 48 h (A), 60 h (B), 72 h (C), and 96 h (D). Symbols: open circles, DCWA; closed circles, cellulase activity; open squares, DCWS; closed squares, ethanol concentration. Arrows indicate the addition times. Error bars denote standard deviation (n = 3)