Table 3.

Comparison of butyric acid production from different substrates by C. tyrobutyricum

Substrate	Hydrolysis method	Fermentation mode	Titer (g L−1)	Yield (g g−1)	Productivity (g L−1 h−1)	References
Lignocellulosic biomass	0.04 M HCl/0.01–0.02 M H2SO4, 121 °C, 30 min, cellulases, 50 °C, 72 h	Batch in serum bottles	42.6	0.36	0.56	[20]
Sorghum stalk and beet molasses	50 mM citrate buffer, cellulases, 50 °C, 18 h	Batch in bioreactors	58.8	0.52	1.9	[42]
Wheat straw	1.4% H2SO4, 163 °C, 15 min, cellulases, 120 h	Batch in serum vials	20.0	0.33	0.21	[22]
SCB	0.1 M HCl, 121 °C, 10–15 min, cellulases, 50 °C, 24 h	Fed-batch in FBB	20.9	0.48	0.5	[25]
JA	0.01 M H2SO4, 121 °C, 30 min	Fed-batch in FBB	60.4	0.38	1.1	[18]
		Repeated-batch in FBB	27.5	0.44	2.75
Brown algae	1.5% H2SO4, 121 °C, 1 h	Fed-batch in FBB	11.0	0.11	0.9	[19]
Cane molasses	5 M H2SO4, 60 °C, 2 h	Fed-batch in FBB	55.2	0.46	3.2	[16]
Corn meal	0.6% amylase, 60 °C	Fed-batch in FBB	46.0	0.45	6.8	[17]
Corn fibre	0.25 M HCl, 121 °C, 45 min	Fed-batch in FBB	29.0	0.47	2.9	[23]
Corn husk	0.4 M H2SO4, 110 °C, 6 h	Repeated batch in FBB	20.8	0.39	0.42	This study

FBB fibrous bed bioreactor, JA Jerusalem artichoke, SCB sugarcane bagasse