Acetate adaptation of clostridia tyrobutyricum for improved fermentation production of butyrate

SpringerPlus

Table 1 Fermentation kinetics of C. tyrobutyricum cultures run in batch with or without selection for acetate tolerance and with or without acetate inhibition

Sugar	Acetate	*C. tyrobutyricum* ²	Lag time³	Complete utilization of carbon	Sugar cons⁴	Butyrate Yield⁵	Final concentration			Specific Growth Rate (μ_net)⁷	Overall produc.⁸
Sugar	(g/L)		(h)	(h)	(g/L/h)	(mol/mol)	(g/L)			(1/h)	(g/L/h)
							Butyrate	Acetate	Bio- mass⁶
Glc¹	0	non-adapted	0	77	1.07	0.85	25.61	8.38	3.40	0.306	0.28
Glc	26.3	non-adapted	94	171	1.09	0.89	26.22	27.85	3.59	0.274	0.15
Glc	26.3	adapted	0	75	1.21	0.87	25.86	32.03	2.77	0.206	0.32
Xyl¹	0	non-adapted	0	166	0.56	0.74	25.80	4.24	2.72	0.093	0.16
Xyl	26.3	non-adapted	102	167	1.22	0.79	29.00	27.76	3.04	0.121	0.12
Xyl	26.3	adapted	25	174	0.60	0.81	28.92	24.46	2.30	0.067	0.17

¹ Glucose and xylose respectively.
² Whether or not the inoculum had been selectively adapted to 26.3 g/L.
³ Calculated as time until sugar consumption started.
⁴ Calculated for the linear sugar consumption phase.
⁵ Yield was calculated as mol butyrate per mol glucose or xylose consumed during fermentation.
⁶ Calculated as DCW g/L.
⁷ As determined by the formula μnet (h^-1) = (ln(DCW_x/DCW₀))/(Time_x-Time₀).
⁸ Overall productivity calculated from the start of the fermentation until the sugar source were completed.