title: Sequential feeding of glucose and valerate in a fed-batch culture of Ralstonia eutropha for production of poly(hydroxybutyrate-co-hydroxyvalerate) with high 3-hydroxyvalerate fraction.
abstract: Several important properties of poly(3-hydroxybutyric-co-3-hydroxyvaleric acids) (P(3HB-co-3HV) depend mainly on the HV unit fraction of the copolymer. Sequential and simultaneous feeding of glucose and valerate were employed to produce P(3HB-co-3HV) in a fed-batch culture of Ralstonia eutropha, and the effects of feeding models on the cell growth, 3HV unit fraction, and copolymer productivity have been investigated. The sequential feeding of glucose and then valerate resulted in a cell density of 110.2 g/L, 3HV unit fraction of 62.7 mol %, and copolymer productivity of 0.56 g/(L.h), while the latter simultaneous feeding strategy never achieved the 3HV fraction of P(3HB-co-3HV) higher than 50%. A nuclear magnetic resonance study confirmed that the production of random copolymer P(3HB-co-3HV) with high 3HV unit fraction was possible even with sequential feeding of glucose and valerate.
authors.affiliation: Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Korea. Lashang@hotmail.com
authors.forename: Longan
authors.initials: L
authors.lastname: Shang
authors.forename: Seong Chun
authors.initials: SC
authors.lastname: Yim
authors.forename: Hyun Gyu
authors.initials: HG
authors.lastname: Park
authors.forename: Ho Nam
authors.initials: HN
authors.lastname: Chang
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D002455:Cell Division; D020118:Cupriavidus necator / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D010421:Pentanoic Acids / Q000302:isolation & purification / Q000378:metabolism; D011091:Polyesters / Q000302:isolation & purification / Q000378:metabolism*; D014631:Valerates / Q000378:metabolism*; D000094122:Polyhydroxybutyrates
chemical_list: D005947:Glucose; D010421:Pentanoic Acids; D011091:Polyesters; D014631:Valerates; C052620:poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate); D000094122:Polyhydroxybutyrates; C013056:beta-hydroxyvaleric acid