title: Accumulation of biodegradable copolyesters of 3-hydroxy-butyrate and 3-hydroxyvalerate in Alcaligenes eutrophus.
abstract: Biodegradable copolyesters of 3-hydroxybutyrate-co-3-hydroxyvalerate (3HB-3HV) were produced by Alcaligenes eutrophus in a two-staged process, namely growth stage and nitrogen-deficient polyester-accumulation stage. When C5 was used as the sole carbon source, the copolyester contained 43 mol % of 3HV. A range of copolyesters with 0-43 mol % of 3HV could be produced by using a medium containing different concentration ratios of butyric acid C4 and C5. Tm of PHB homopolymer was 177.6 degrees C and that of copolyester with highest 3HV mol fraction of 43% was 99.0 degrees C. C5 concentration in the medium could be an effective means to control the polymeric composition and mechanical properties of the copolyesters accumulated in A. eutrophus.
authors.affiliation: Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom.
authors.forename: H
authors.initials: H
authors.lastname: Chua
authors.forename: P H
authors.initials: PH
authors.lastname: Yu
authors.forename: W
authors.initials: W
authors.lastname: Lo
mesh_terms: D020155:3-Hydroxybutyric Acid; D000421:Alcaligenes / Q000378:metabolism*; D001673:Biodegradation, Environmental; D005591:Chemical Fractionation; D003470:Culture Media; D006885:Hydroxybutyrates / Q000032:analysis* / Q000737:chemistry; D010421:Pentanoic Acids / Q000032:analysis* / Q000737:chemistry; D011091:Polyesters / Q000737:chemistry; D013696:Temperature; D018505:Waste Management
chemical_list: D003470:Culture Media; D006885:Hydroxybutyrates; D010421:Pentanoic Acids; D011091:Polyesters; C013056:beta-hydroxyvaleric acid; D020155:3-Hydroxybutyric Acid