Table 2.

Production of volatile fatty acids by microorganisms.

Volatile Fatty Acid	Bacteria	Substrate	Concentration (g/L)	Productivity (g/L/h)	References
Acetic acid	Acetobacter aceti	cheese whey	96.9	4.060	[40]
	Clostridium acetium	mixed gas (4% H2:18% Argon:78% CO)	1.3	nd	[41]
	Clostridium lentocellum SG6	paddy straw	30.9	nd	[42]
	Moorella thermoacetica	sugarcane straw hydrolysate	17.2	nd	[43]
	Saccharomyces cerevisiae + Acetobacter pasteurianus	glucose	66.0	0.367	[44]
Propionic acid	Propionibacterium acidipropionici (ATCC 4965)	lactate	15.1	0.113	[45]
		glycerol	6.8	0.051
		sugarcane molasses	8.2	0.062
	Propionibacterium acidipropionici (CGMCC 1.223)	glycerol	44.6	0.200	[46]
	Propionibacterium acidipropionici (ATCC 4875)	hemicellulose hydrolysate	18.0	nd	[47]
		chesse whey	19.7	0.980	[48]
	Propionibacterium freudenreichii CCTCC M207015	glucose	67.1	0.140	[49]
	Propionibacterium freudenreichii spp. shermanii	glycerol	9.0	0.180	[50]
Butyric acid	Clostridium butyricum S21	sucrose	20.0	0.210	[51]
	Clostridium butyricum ZJUCB	glucose	16.7	nd	[52]
	Clostridium thermobutyricum JW171K	glucose	18.4	2.400	[53]
	Clostridium tyrobutyricum	corn husk hydrolysate	20.8	0.420	[54]
		sugarcane bagasse hydrolysate	20.9	0.510	[55]

nd—not determine.