Table 4.

Comparison of steady-state H₂ and biomass production by C. saccharolyticus, C. kristjanssonii and their co-culture in glucose-limited chemostat cultivations at two different dilution rates (yeast extract, 1 g L^-1; pH 6.7; 70°C).

Organism(s)	D (h-1)	$Y_{{\text{H}}_{\text{2}}}$[mol (mol C6)-1]	$Q_{{\text{H}}_{\text{2}}}$(mmol L-1 h-1)	$q_{{\text{H}}_2}$(mmol gCDW-1 h-1)	Biomass concentration (gCDW L-1)	Ysx [gCDW (mol C6)-1]	Residual glucose (mM)
C. saccharolyticus	0.06	3.5 ± 0.1	4.9 ± 0.14	13.2 ± 0.1	0.38 ± 0.01	15.8 ± 0.2	0
	0.15	3.1 ± 0.2	7 ± 0.3	24.4 ± 1	0.29 ± 0.03	19.3 ± 1.1	8.6 ± 0.6
C. kristjanssonii	0.06	3.5 ± 0.1	4.8 ± 0.1	17.8 ± 0.5	0.27 ± 0.01	11.7 ± 0.0	0
	0.15	3.0 ± 0.1	10.3 ± 0.16	34.6 ± 1.6	0.3 ± 0.02	13.0 ± 0.1	0.2 ± 0.0
Co-culture	0.06	3.7 ± 0.0	4.8 ± 0.2	14.8 ± 0.8	0.33 ± 0.03	15.4 ± 0.8	0
	0.15	3.5 ± 0.0	10.4 ± 0.14	21.4 ± 0.8	0.49 ± 0.01	24.6 ± 0.8	0

Values are means of two independent replicates ± standard deviation.