title: Biosynthesis of poly(3-hydroxybutyrate) and its copolymers by Yangia sp. ND199 from different carbon sources.
abstract: A halophilic bacterium isolated from mangrove soil sample in Northern Vietnam, Yangia sp. ND199 was found capable of producing homopolymer poly(3-hydroxybutyrate) [P(3HB)], copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)], and copolymer poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] from different carbon sources. The presence of 3HB, 3HV, and 4HB monomers were confirmed by gas chromatography and nuclear magnetic resonance analysis. Only P(3HB) was produced using carbon sources such as fructose or by a combination of fructose with 1,5-pentanediol, 1,6-hexanediol, sodium hexanoate, or sodium octanoate. The biosynthesis of P(3HB-co-3HV) was achieved by adding cosubstrates such as sodium valerate and sodium heptanoate. When 1,4-butanediol, γ-butyrolactone or sodium 4-hydroxybutyrate was added to the culture medium, P(3HB-co-4HB) containing 4.0-7.1mol% 4HB fraction was accumulated. The molecular weights and thermal properties of polyesters were determined by gel permeation chromatography and differential scanning calorimeter, respectively. The results showed that Yangia sp. ND199 is able to produce polyester with high weight average molecular weight ranging from 1.3×10(6) to 2.2×10(6) Dalton and number average molecular weight ranging from 4.2×10(5) to 6.9×10(5) Dalton. The molecular weights, glass transition temperature as well as melting temperature of homopolymer P(3HB) are higher than those of copolymer P(3HB-co-3HV) or P(3HB-co-4HB).
authors.affiliation: Department of Microbiology and Biotechnology, Faculty of Biology, Hanoi National University of Education, 136 Xuanthuy, Caugiay, Hanoi, Viet Nam.
authors.forename: Tran
authors.initials: T
authors.lastname: Huu Phong
authors.affiliation: Department of Microbiology and Biotechnology, Faculty of Biology, Hanoi National University of Education, 136 Xuanthuy, Caugiay, Hanoi, Viet Nam. Electronic address: thuocdv@hnue.edu.vn.
authors.forename: Doan
authors.initials: D
authors.lastname: Van Thuoc
authors.affiliation: School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia.
authors.forename: Kumar
authors.initials: K
authors.lastname: Sudesh
mesh_terms: D020561:Alphaproteobacteria / Q000378:metabolism*; D002152:Calorimetry, Differential Scanning; D002244:Carbon / Q000378:metabolism*; D005285:Fermentation; D006885:Hydroxybutyrates / Q000737:chemistry / Q000378:metabolism*; D008970:Molecular Weight; D011091:Polyesters / Q000737:chemistry / Q000378:metabolism*; D011108:Polymers / Q000737:chemistry / Q000378:metabolism*; D066244:Proton Magnetic Resonance Spectroscopy; D000094122:Polyhydroxybutyrates
chemical_list: D002244:Carbon; D006885:Hydroxybutyrates; D011091:Polyesters; D011108:Polymers; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates
keywords: Copolymer; Poly(3-hydroxybutyrate); Poly(3-hydroxybutyrate-co-3-hydroxyvalerate); Poly(3-hydroxybutyrate-co-4-hydroxybutyrate); Yangia sp. ND199