title: Microbial consortia for hydrogen production enhancement.
abstract: Ten efficient hydrogen-producing strains affiliated to the Clostridium genus were used to develop consortia for hydrogen production. In order to determine their saccharolytic and proteolytic activities, glucose and meat extract were tested as fermentation substrates, and the best hydrogen-producing strains were selected. The C. roseum H5 (glucose-consuming) and C. butyricum R4 (protein-degrading) co-culture was the best hydrogen-producing co-culture. The end-fermentation products for the axenic cultures and co-cultures were analyzed. In all cases, organic acids, mainly butyrate and acetate, were produced lowering the pH and thus inhibiting further hydrogen production. In order to replace the need for reducing agents for the anaerobic growth of clostridia, a microbial consortium including Clostridium spp. and an oxygen-consuming microorganism able to form dense granules (Streptomyces sp.) was created. Increased yields of hydrogen were achieved. The effect of adding a butyrate-degrading bacteria and an acetate-consuming archaea to the consortia was also studied.
authors: Department of Molecular Biology, Autonoma University of Madrid, C/Darwin 2, 28049, Madrid, Spain. hayfa_rajhi@yahoo.fr
authors: Haifa
authors: H
authors: Rajhi
authors: Emiliano E
authors: EE
authors: Díaz
authors: Patricia
authors: P
authors: Rojas
authors: José L
authors: JL
authors: Sanz
mesh_terms: D000693:Anaerobiosis; D002264:Carboxylic Acids / Q000378:metabolism; D003013:Clostridium / Q000254:growth & development / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D059013:Microbial Consortia; D010461:Peptones / Q000378:metabolism
chemical_list: D002264:Carboxylic Acids; D003470:Culture Media; D010461:Peptones; D006859:Hydrogen; D005947:Glucose
references: Curr Microbiol. 2011 Feb;62(2):486-91
references: 20814681
references: Microbiol Rev. 1986 Dec;50(4):484-524
references: 3540574
references: Sci China C Life Sci. 2005 Apr;48(2):155-62
references: 15986888
references: Bioresour Technol. 2011 Sep;102(18):8437-44
references: 21429742
references: J Appl Microbiol. 2007 Nov;103(5):1415-23
references: 17953552
references: Biotechnol Bioeng. 2002 Apr 5;78(1):44-52
references: 11857280
references: Appl Microbiol Biotechnol. 1996 Dec;46(5-6):587-92
references: 9008891