title: Effect of pH on hydrogen production from glucose by a mixed culture.
abstract: The effect of pH on the conversion of glucose to hydrogen by a mixed culture of fermentative bacteria was evaluated. At 36 degrees C, six hours hydraulic retention, over 90% of glucose was degraded at pH ranging 4.0-7.0, producing biogas and an effluent comprising mostly fatty acids. At the optimal pH of 5.5, the biogas comprised 64 +/- 2% of hydrogen with a yield of 2.1 +/- 0.1 mol-H2/mol-glucose and a specific production rate of 4.6 +/- 0.4 l-H2/(g-VSS day). The effluent was composed of acetate (15.3-34.1%) and butyrate (31.2-45.6%), plus smaller quantities of other volatile fatty acids and alcohols. The diversity of microbial communities increased with pH, based on 16S rDNA analysis by denaturing gradient gel electrophoresis (DGGE).
authors.affiliation: Centre for Environmental Engineering Research, Department of Civil Engineering, University of Hong Kong. hrechef@hkucc.hku.hk
authors.forename: Herbert H P
authors.initials: HH
authors.lastname: Fang
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
mesh_terms: D000438:Alcohols / Q000378:metabolism; D001419:Bacteria / Q000378:metabolism; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005285:Fermentation; D005947:Glucose / Q000378:metabolism*; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D012722:Sewage / Q000382:microbiology*
chemical_list: D000438:Alcohols; D005232:Fatty Acids, Volatile; D012722:Sewage; D006859:Hydrogen; D005947:Glucose