Table 2

Xylose and arabinose consumption rates and product yields from anaerobic batch fermentations by strains BWY02.XA (xylose and arabinose-growing laboratory strain), TMB 3400 (xylose-growing industrial strain) and TMB 3063 (xylose and arabinose-growing industrial strain). Defined mineral medium with mixtures of 20 g/l glucose and 20 g/l xylose or 20 g/l glucose and 20 g/l arabinose as well as 20 g/l glucose, 20 g/l xylose and 20 g/l arabinose were used as indicated. Product yields are calculated from the pentose phase of the fermentation. (n.a. not applicable; n.d. not detected)

Substrate
Strain
qxylose
(g xylose h-1 g cells-1)
qarabinose
(g arabinose h-1 g cells-1)
Yarabitol
(g arabitol g arabinose-1)
Yxylitol
(g xylitol g xylose-1)
Yglycerol
(g glycerol g pentose-1)
Yacetate
(g acetate g pentose-1)
Yethanol
(g ethanol g pentose-1)
final ethanol concentration (g l-1)

Glucose + xylose
BWY02.XA
0.1 ± 0.0
n.a.
n.a.
0.34 ± 0.01
0.12 ± 0.01
0.02 ± 0.00
0.23 ± 0.01
14.2 ± 0.7
Glucose + arabinose
BWY02.XA
n.a.
0.03 ± 0.00
0.77 ± 0.22
n.a.
0.00 ± 0.02
0.10 ± 0.04
n.d.
9.0 ± 2.0
Glucose + xylose + arabinose
BWY02.XA
0.041 ± 0.080
0.035 ± 0.014
1.14 ± 0.18
0.33 ± 0.03
n.d.
n.d.
0.07 ± 0.1
10.4 ± 2.2

TMB 3400
0.066 ± 0.015
0.01 ± 0.00
approx. 1*
0.42 ± 0.00
0.01 ± 0.00
n.d.
0.09 ± 0.0
12.8 ± 0.5

TMB 3063
0.042 ± 0.002
0.029 ± 0.002
0.68 ± 0.17
0.11 ± 0.03
0.03 ± 0.00
0.06 ± 0.01
0.16 ± 0.03
14.7 ± 2.0

(* not possible to measure due to small amounts of arabinose consumed and arabitol produced)

Karhumaa et al. Microbial Cell Factories 2006 5:18   doi:10.1186/1475-2859-5-18