title: Biosynthesis of poly(hydroxybutyrate-hydroxyvalerate) from the acclimated activated sludge and microbial characterization in this process.
abstract: This study investigated the effects of substrate composition (acetate and propionate) on synthesis of various mix of poly(hydroxybutyrate-hydroxyvalerate) (P(HB/HV)) from activated sludge, which was acclimated using a single carbon (acetate) and mixed carbons (acetate and propionate). Results of batch P(HB/HV) production tests indicated that the yield and synthesis rate of P(HB/HV) decreased as the proportion of propionate in the substrate increased. However, mixed-carbon-acclimated sludge with acetate and propionate exhibited better P(HB/HV) production performance than with acetate-acclimated sludge in terms of substrate utilization, yield of P(HB/HV) and HV fraction in P(HB/HV). The desired hydroxyvalerate (HV) fraction (0-74%) of the P(HB/HV) could be obtained based on the substrate composition and sludge acclimation. Furthermore, PCR-DGGE analysis indicated that specific species dominated the activated sludge used for P(HB/HV) production. Acidobacteria and Burkholderiales were the dominant bacterial populations and played an important role in HV synthesis.
authors.affiliation: Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, The Key Laboratory for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen, PR China. Electronic address: wypp@xmu.edu.cn.
authors.forename: Yuanpeng
authors.initials: Y
authors.lastname: Wang
authors.forename: Jiyuan
authors.initials: J
authors.lastname: Cai
authors.forename: Jianghuang
authors.initials: J
authors.lastname: Lan
authors.forename: Zhenggui
authors.initials: Z
authors.lastname: Liu
authors.forename: Ning
authors.initials: N
authors.lastname: He
authors.forename: Liang
authors.initials: L
authors.lastname: Shen
authors.forename: Qingbiao
authors.initials: Q
authors.lastname: Li
mesh_terms: D000064:Acclimatization; D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D004275:DNA, Ribosomal / Q000235:genetics; D058645:Denaturing Gradient Gel Electrophoresis; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D010802:Phylogeny; D011091:Polyesters / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D012722:Sewage / Q000382:microbiology*; D013816:Thermodynamics; D013997:Time Factors; D000094122:Polyhydroxybutyrates
chemical_list: D004275:DNA, Ribosomal; D011091:Polyesters; D012722:Sewage; C052620:poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate); D000094122:Polyhydroxybutyrates
keywords: Activated sludge; COD; DGGE; DO; HB; HRT; HV; MLVSS; MPCC; MPCT; Microbial community; P(HB/HV); P(HB/HV) yield; PCR; PHAs; PHB; PHV; SBR; SRT; Substrate composition; TCA cycle; VSS; X; Y(P(HB/HV)); biomass; chemical oxygen demand; denaturing gradient-gel-electrophoresis; dissolved oxygen; hydraulic retention time; hydroxybutyrate; hydroxyvalerate; maximum P(HB/HV) concentration; maximum P(HB/HV) content; mixed liquor volatile suspended solid; poly(hydroxybutyrate-hydroxyvalerate); polyhydroxyalkanoates; polyhydroxybutyrate; polyhydroxyvalerate; polymerase chain reaction; q(P(HB/HV)); q(s); sequencing biological reactor; solid retention time; specific P(HB/HV) synthesis rate; specific substrate consumption; tricarboxylic acid cycle; volatile suspended solid