Table 4.

Comparison of batch ABE fermentations by C. acetobutylicum TSH1 and symbiotic system

	C. acetobutylicum TSH1 with pretreatment	Symbiotic system without pretreatment	Symbiotic system with air sparging
Glucose consumed (g/L)	49.5 ± 1.0	50.4 ± 1.8	58.6 ± 1.0
Acetone (g/L)	4.9 ± 0.1	4.9 ± 0.1	3.1 ± 0.2
Butanol (g/L)	11.1 ± 0.9	11.0 ± 0.5	11.2 ± 0.7
Ethanol (g/L)	2.3 ± 0.04	2.2 ± 0.1	2.6 ± 0.07
Total ABE (g/L)	18.3 ± 1.8	18.1 ± 1.2	16.9 ± 0.9
Butanol yield (g/g)	0.22 ± 0.01	0.22 ± 0.01	0.18 ± 0.01
ABE yield (g/g)	0.37 ± 0.01	0.36 ± 0.01	0.29 ± 0.01
Butanol productivity (g/L h)	0.26 ± 0.01	0.21 ± 0.01	0.23 ± 0.01
ABE productivity (g/L h)	0.44 ± 0.01	0.38 ± 0.01	0.37 ± 0.01