Table 4 Substrate consumption and product formation parameters during anaerobic batch fermentation of mixed sugars in defined mineral medium
TMB3664 (D-xylose/L-arabinose pathway) | TMB3665 (D-xylose pathway) | |||
|---|---|---|---|---|
Medium | G-A-X | G-A | G-A-X | |
Overall process | Initial glucose g/l | 20.7 ± 0.2 | 20.1 ± 0.9 | 20.1 ± 0.4 |
Initial L-arabinose g/l | 22.1 ± 0.2 | 23.1 ± 0.4 | 22.1 ± 0.1 | |
Initial xylose g/l | 21.7 ± 0.4 | - | 20.8 ± 0.3 | |
Consumed arabinose g/l | 3.9 ± 0.2 | 2.1 ± 0.1 | 3.1 ± 0.3 | |
Consumed xylose g/l | 14.1 ± 0.2 | - | 13.7 ± 0.2 | |
Final ethanol titer+ g/l | 15.3 ± 0.0 | 9.3 ± 0.4 | 14.3 ± 0.3 | |
Y ethanol, total sugars (g ethanol)/(g sugar) | 0.23 ± 0.00 | 0.21 ± 0.01 | 0.22 ± 0.01 | |
Y ethanol, consumed sugars (g ethanol)/(g sugar) | 0.40 ± 0.01 | 0.42 ± 0.01 | 0.39 ± 0.00 | |
Y xylitol, consumed xylose (g xylitol)/(g consumed D-xylose) | 0.09 ± 0.01 | - | 0.10 ± 0.0 | |
Y xylitol, consumed C5 (g xylitol) (g consumed sugar)-1 | 0.07 ± 0.00 | n.d. | 0.08 ± 0.0 | |
Y arabitol, consumed arabinose (g L-arabitol)/(g consumed L-arabinose) | 0.48 ± 0.01 | 0.39 ± 0.03 | 0.90 ± 0.07 | |
Pentose Phasea | q arabinose (g L-arabinose)/(g cells)/h | 0.021 ± 0.001 | 0.011 ± 0.001 | 0.013 ± 0.000 |
q xylose (g D-xylose)/(g cells)/h | 0.080 ± 0.001 | - | 0.077 ± 0.001 | |
q ethanol (g ethanol)/(g cells)/h | 0.035 ± 0.001 | 0.003 ± 0.001 | 0.029 ± 0.001 | |
Biomass, produced from C5 g/l | 0.37 ± 0.01 | n.d. | 0.25 ± 0.03 | |
Y biomass, produced from C5 (g biomass)/(g consumed sugar) | 0.025 ± 0.001 | - | 0.019 ± 0.002 | |
Y ethanol, produced from C5 (g ethanol)/(g consumed sugar) | 0.35 ± 0.01 | 0.35 ± 0.01 | 0.32 ± 0.01 | |
Y glycerol, produced from C5 (g glycerol)/(g sugar) | 0.03 ± 0.01 | 0.06 ± 0.02 | 0.02 ± 0.00 | |