Biohydrogen production from glucose using submerged dynamic filtration module: Metabolic product distribution and flux-based analysis

A lab scale bioreactor with the submerged polyester mesh of pore size 100 mu m, was used for biohydrogen production under mesophilic condition (35 degrees C). The reactor was continuously fed with glucose (15 g/L) for 90 days with a hydraulic retention time (HRT), ranging from 12 to 1.5 h. Peak hydrogen yield (HY) was achieved at 3 h HRT as 3.22 +/- 0.22 mol H-2/mol glucose (added) and the hydrogen production rate was achieved at 2 h HRT as 54.07 +/- 3.69 L H-2/L-d, respectively. When HRT was reduced to 1.5 h, the hydrogen yield decreased to 1.04 +/- 0.44 mol H-2/mol glucose (added). Washout of the hydrogen producing population and metabolic flux shift to non-hydrogen producing at 1.5 h HRT might have attributed to the lower performance of the bioreactor.