Biosynthesis and characterization of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) produced by Burkholderia cepacia D1.
Copolyesters of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV) were produced by Burkholderia cepacia D1 at 30 degrees C in nitrogen-free culture solutions containing n-butyric acid and/or n-valeric acid. When n-valeric acid was used as the sole carbon source, the 3HV fraction in copolyester increased from 36 to 90 mol% as the concentration of n-valeric acid in the culture solution increased from 1 to 20 g/l. The addition of n-butyric acid to the culture solution resulted in a decrease in the 3HV fraction in copolyester. The copolymers biosynthesized by this method were mixtures of random copolymers having a wide variety of composition of the 3HV component. The melting points of the fractionated copolymers show a concave curve with the minimum at the 3HV content of approximately 40 mol%. The alpha-parameter of lattice indices of the P(3HB) crystal for the fractionated copolymers largely increased as the 3HV composition increased. Biodegradability of the copolymer increased with the lower content of 3HV composition and/or the lower crystallinity.
Mitomo
H
H
Department of Biological and Chemical Engineering, Faculty of Engineering, Gunma University, Kiryu, Japan.
Takahashi
T
T
Ito
H
H
Saito
T
T
D016956:Burkholderia cepacia / Q000378:metabolism*; D020148:Butyric Acid / Q000378:metabolism*; D002265:Carboxylic Ester Hydrolases / Q000378:metabolism; D005591:Chemical Fractionation; D003460:Crystallization; D005285:Fermentation; D006358:Hot Temperature; D009682:Magnetic Resonance Spectroscopy; D008970:Molecular Weight; D010421:Pentanoic Acids / Q000378:metabolism*; D011091:Polyesters / Q000737:chemistry* / Q000378:metabolism*; D014961:X-Ray Diffraction; D000094122:Polyhydroxybutyrates
D020148:Butyric Acid; D002265:Carboxylic Ester Hydrolases; D010421:Pentanoic Acids; D011091:Polyesters; C052620:poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate); D000094122:Polyhydroxybutyrates; C022417:poly-beta-hydroxybutyrate depolymerase; C038780:n-pentanoic acid