title: Production of poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) by Ralstonia eutropha from soybean oil.
abstract: High-yield production of polyhydroxyalkanoates (PHAs) by Ralstonia eutropha KCTC 2662 was investigated using soybean oil and γ-butyrolactone as carbon sources. In flask culture, it was shown that R. eutropha KCTC 2662 accumulated PHAs during the growth phase. The optimum carbon to nitrogen ratio (C/N ratio) giving the highest cell and PHA yield was 20 g-soybean oil/g-(NH(4))(2)SO(4). The 4-hydroxybutyrate (4HB) fraction in the copolymer was not strongly affected by the C/N ratio. In a 2.5-L fermentor, a homopolymer of poly(3-hydroxybutyrate) [P(3HB)] was produced from soybean oil as the sole carbon source by batch and fed-batch cultures of R. eutropha with dry cell weights of 15-32 g/L, PHA contents of 78-83 wt% and yields of 0.80-0.82 g-PHA/g-soybean oil used. By co-feeding soybean oil and γ-butyrolactone as carbon sources, a copolymer of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] could be produced with dry cell weights of 10-21 g/L, yields of 0.45-0.56 g-PHA/g-soybean oil used (0.39-0.50g-PHA/g-carbon sources used) and 4HB fractions of 6-10 mol%. Higher supplementation of γ-butyrolactone increased the 4HB fraction in the copolymer, but decreased cell and PHA yield.
authors.affiliation: Department of Chemical Engineering, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea.
authors.forename: Dae Hoo
authors.initials: DH
authors.lastname: Park
authors.forename: Beom Soo
authors.initials: BS
authors.lastname: Kim
mesh_terms: D015107:4-Butyrolactone / Q000494:pharmacology; D020118:Cupriavidus necator / Q000254:growth & development*; D006885:Hydroxybutyrates / Q000378:metabolism*; D011091:Polyesters / Q000378:metabolism*; D012997:Solvents / Q000494:pharmacology; D013024:Soybean Oil / Q000378:metabolism / Q000494:pharmacology*; D000094122:Polyhydroxybutyrates
chemical_list: D015107:4-Butyrolactone; D006885:Hydroxybutyrates; D011091:Polyesters; D012997:Solvents; D013024:Soybean Oil; C068056:poly(3-hydroxybutyrate-co-4-hydroxybutyrate); D000094122:Polyhydroxybutyrates; C003182:poly-beta-hydroxybutyrate