Strategies for improved isopropanol–butanol production by a Clostridium strain from glucose and hemicellulose through consolidated bioprocessing

Table 2 Metabolic products and enzymatic activities of Clostridium sp. strain NJP7

	Control	With VB3	With butyrate + VB3
Acetone (g/L)	0.93	0.89	2.21
Isopropanol (g/L)	0.55	0.72	1.92
Butanol (g/L)	5.14	6.28	12.21
Ratio of isopropanol:acetone	0.59:1	0.81:1	0.87:1
Glucose consumption (g/L)	20.18	21.87	41.98
AIB yield (g/g)	0.33	0.36	0.39
Max. OD (A600)	4.51	4.98	5.62
s-ADH^a (U/mg)	0.19	0.31	0.46
ADH^a (U/mg)	0.26	0.32	0.58

Control fermentation without addition of any exogenous acids and pH adjustment
Other experiments fermentation with addition of VB3 (20 mg/L) or butyrate (60 mM) and VB3(20 mg/L) without pH adjustment
^aAll of the samples were collected at their exponential phases for detection of their s-ADH and ADH activities: 24 h for Control and With VB3; 18 h for W With butyrate and VB3

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