title: Optimization of glutamate concentration and pH for H production from volatile fatty acids by Rhodopseudomonas capsulata.
abstract: OBJECTIVE
  This study attempted to employ response surface methodology (RSM) to evaluate the effects of glutamate concentration and pH on H(2) production from volatile fatty acids by Rhodopseudomonas capsulata.
  
  
  RESULTS
  A mixture of acetate, propionate and butyrate was used as a carbon source for the H(2) production by R. capsulata. The H(2) yield and H(2) production rate were strongly affected by the glutamate concentration, pH and their interaction. The predicted maximum H(2) yield of 0.534 was obtained when glutamate concentration and pH were 6.56 mmol l(-1) and 7.29 respectively. On the contrary, the maximum H(2) production rate of 18.72 ml l(-1) h(-1) was achieved at a glutamate concentration of 7.01 mmol l(-1) and pH 7.31.
  
  
  CONCLUSIONS
  Taking H(2) yield and H(2) production rate together into account, a glutamate concentration of 6.56-7.01 mmol l(-1) and pH of 7.29-7.31 should be selected for H(2) production from a mixture of acetate, propionate and butyrate by R. capsulata.
  
  
  CONCLUSIONS
  The RSM was a useful tool for maximizing H(2) production by photosynthetic bacteria (PSB).
authors.affiliation: Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, China.
authors.forename: X-Y
authors.initials: XY
authors.lastname: Shi
authors.forename: H-Q
authors.initials: HQ
authors.lastname: Yu
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D002087:Butyrates / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry; D005232:Fatty Acids, Volatile / Q000378:metabolism*; D018698:Glutamic Acid / Q000378:metabolism / Q000494:pharmacology*; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D011422:Propionates / Q000378:metabolism; D016354:Rhodobacter capsulatus / Q000378:metabolism*
chemical_list: D002087:Butyrates; D003470:Culture Media; D005232:Fatty Acids, Volatile; D011422:Propionates; D018698:Glutamic Acid; D006859:Hydrogen; C029658:propionic acid; D019342:Acetic Acid