TABLE 2.

Effects of additives on growth and ethanol production by KO11 in CSL medium containing 1% corn steep liquor and 10% xylose

Additive	No.	Concn		Cell yield		Volumetric production of ethanola		Maximum ethanol production		Yield (%)b
		mg ml−1	mM	Avge	% of control	g liter−1 h−1	% of control	mg ml−1	% of control
None (control)	26			0.94 ± 0.15	100	0.38 ± 0.08	100	31.12 ± 4.64	100	61
Sodium pyruvate	3	0.5	4.6	1.32 ± 0.32	140	0.55 ± 0.17	144	37.60 ± 5.91	121	74
Sodium pyruvate	3	1.0	9.1	1.49 ± 0.30	158	0.66 ± 0.17	173	40.09 ± 5.53	129	79
Sodium pyruvate	15	2.0	18.2	1.99 ± 0.20	212	0.81 ± 0.14	213	44.22 ± 2.69	142	87
Sodium pyruvate	3	4.4	36.4	2.08 ± 0.08	221	0.83 ± 0.01	218	43.23 ± 1.50	139	85
Acetaldehyde (half initially + half after 12 h)	4	0.5 (total)	11.4	1.55 ± 0.07	165	0.60 ± 0.35	158	44.05 ± 1.89	142	86
Citric acid	2	2.0	10.4	0.88, 0.75	86	0.35, 0.33	89	30.00, 27.59	93	56
Isocitric acid	2	2.0	6.6	1.11, 0.88	105	0.51, 0.36	113	36.45, 29.59	106	65
Sodium 2-ketoglutarate	5	2.0	11.9	1.89 ± 0.18	201	0.84 ± 0.08	221	41.54 ± 1.24	133	81
Oxaloacetic acid	2	2.0	15.1	0.75, 0.75	80	0.28, 0.28	74	23.58, 23.64	76	46
Sodium malate	2	2.0	11.2	0.76, 0.84	85	0.27, 0.27	71	23.89, 24.97	79	48
Sodium fumarate	2	2.0	12.5	0.80, 0.96	91	0.37, 0.32	92	27.15, 29.84	92	56
Sodium succinate	3	2.0	7.4	1.00 ± 0.12	106	0.41 ± 0.05	108	35.00 ± 1.31	112	69
Potassium glutamate	3	2.0	10.8	1.66 ± 0.17	177	0.66 ± 0.13	174	43.14 ± 0.13	139	85
Aspartic acid	2	2.0	15.0	0.85, 0.82	88	0.33, 0.32	84	28.40, 27.40	90	55

^aVolumetric production was calculated by determining the average hourly rate of ethanol production between 24 and 48 h after inoculation.

^bYield is expressed as a percentage of the theoretical yield (100% = 0.51 g of ethanol per g of xylose).