title: Bioconversion of glycerine pitch into a novel yellow-pigmented P(3HB-co-4HB) copolymer: synergistic effect of ammonium acetate and polymer characteristics.
abstract: Glycerine pitch waste generated from oleochemical industry was exploited as a carbon source for poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P(3HB-co-4HB)) copolymer production by a novel, yellow-pigmented bacterium Cupriavidus sp. USMAHM13 to improve the economics of microbial polyhydroxyalkanoate production and to establish a feasible waste management approach. Medium optimization using response surface methodology through shake-flask fermentation had led to the accumulation of P(3HB-co-51%4HB) copolymer using a combination of glycerine pitch (10 g/l), 1,4-butanediol (8.14 g/l), and ammonium acetate (2.39 g/l). P(3HB-co-4HB) copolymers with 4HB monomer compositions ranged from 3 to 40 mol% were obtained through batch fermentation in a bioreactor using different concentrations of ammonium acetate. The copolymers exhibited a wide range of material properties depending on the monomer composition and type of carbon sources. P(3HB-co-40%4HB) was a typical random copolymer, whereas other P(3HB-co-4HB) produced were blend copolymers. Carotenoid pigment which was produced simultaneously with the polymer production was found to have negligible effect on the mechanical and thermal properties of the P(3HB-co-4HB) copolymer films.
authors.forename: Hema
authors.initials: H
authors.lastname: Ramachandran
authors.forename: A A
authors.initials: AA
authors.lastname: Amirul
mesh_terms: D000085:Acetates / Q000494:pharmacology*; D000704:Analysis of Variance; D061249:Batch Cell Culture Techniques; D018533:Biomass; D001704:Biopolymers / Q000737:chemistry; D019149:Bioreactors / Q000382:microbiology; D049921:Cupriavidus / Q000187:drug effects / Q000254:growth & development / Q000502:physiology; D005285:Fermentation / Q000187:drug effects; D005990:Glycerol / Q000378:metabolism*; D006885:Hydroxybutyrates / Q000378:metabolism*; D008970:Molecular Weight; D010858:Pigmentation / Q000187:drug effects; D011091:Polyesters / Q000378:metabolism*; D011108:Polymers / Q000378:metabolism*; D012044:Regression Analysis; D015203:Reproducibility of Results; D013696:Temperature; D013997:Time Factors; D000094122:Polyhydroxybutyrates
chemical_list: D000085:Acetates; D001704:Biopolymers; D005990:Glycerol; D006885:Hydroxybutyrates; D011091:Polyesters; D011108:Polymers; C068056:poly(3-hydroxybutyrate-co-4-hydroxybutyrate); D000094122:Polyhydroxybutyrates; C018824:ammonium acetate