Table 3. Metabolite analysis in the semi-continuous subculture.

	Ethanol (mM)	Acetate (mM)	Propionate (mM)	Butyrate (mM)	Caproate (mM)
PEC-HZ
Start-up	0.64 ± 0.10	1.26 ± 0.08	0.26 ± 0.02	0.11 ± 0.08	0.43 ± 0.18
Generation l	8.91 ± 4.64	5.28 ± 0.44	2.07 ± 0.23	1.48 ± 0.09	1.10 ± 0.08
Generation 2	7.55 ± 0.07	1.31 ± 0.10	0.02 ± 0.00	8.30 ± 0.30	4.72 ± 0.00
PEM-HZ
Start-up	0.59 ± 0.34	0.72 ± 0.29	0.37 ± 0.16	0.15 ± 0.10	0.37 ± 0.27
Generation l	0	5.84 ± 2.55	2.46 ± 1.76	0.54 ± 0.51	0.80 ± 0.33
Generation 2	0	5.06 ± 0.36	0.65 ± 0.54	0.21 ± 0.05	0