title: Evaluation of medium-chain-length polyhydroxyalkanoate production by Pseudomonas putida LS46 using biodiesel by-product streams.
abstract: Medium-chain-length polyhydroxyalkanoate (mcl-PHA) production by Pseudomonas putida LS46 was analyzed in shake-flask-based batch reactions, using pure chemical-grade glycerol (PG), biodiesel-derived "waste" glycerol (WG), and biodiesel-derived "waste" free fatty acids (WFA). Cell growth, substrate consumption, mcl-PHA accumulation within the cells, and the monomer composition of the synthesized biopolymers were monitored. The patterns of mcl-PHA synthesis in P. putida LS46 cells grown on PG and WG were similar but differed from that of cells grown with WFA. Polymer accumulation in glycerol-based cultures was stimulated by nitrogen limitation and plateaued after 48 h in both PG and WG cultures, with a total accumulation of 17.9% cell dry mass and 16.3% cell dry mass, respectively. In contrast, mcl-PHA synthesis was independent of nitrogen concentration in P. putida LS46 cells cultured with WFA, which accumulated to 29% cell dry mass. In all cases, the mcl-PHAs synthesized consisted primarily of 3-hydroxyoctanoate (C(8)) and 3-hydroxydecanoate (C(10)). WG and WFA supported similar or greater cell growth and mcl-PHA accumulation than PG under the experimental conditions used. These results suggest that biodiesel by-product streams could be used as low-cost carbon sources for sustainable mcl-PHA production.
authors.affiliation: a Department of Biosystems Engineering, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
authors.forename: Jilagamazhi
authors.initials: J
authors.lastname: Fu
authors.forename: Umesh
authors.initials: U
authors.lastname: Sharma
authors.forename: Richard
authors.initials: R
authors.lastname: Sparling
authors.forename: Nazim
authors.initials: N
authors.lastname: Cicek
authors.forename: David B
authors.initials: DB
authors.lastname: Levin
mesh_terms: D056804:Biofuels; D002210:Caprylates; D002244:Carbon / Q000378:metabolism; D005230:Fatty Acids, Nonesterified / Q000378:metabolism*; D005990:Glycerol / Q000378:metabolism*; D007220:Industrial Waste; D009584:Nitrogen / Q000378:metabolism; D054813:Polyhydroxyalkanoates / Q000737:chemistry / Q000378:metabolism*; D016958:Pseudomonas putida / Q000254:growth & development / Q000378:metabolism*; D062065:Wastewater / Q000382:microbiology
chemical_list: D056804:Biofuels; D002210:Caprylates; D002244:Carbon; D005230:Fatty Acids, Nonesterified; D005990:Glycerol; D007220:Industrial Waste; D009584:Nitrogen; D054813:Polyhydroxyalkanoates; D062065:Wastewater; C101940:3-hydroxyoctanoic acid
keywords: PHA-cm; Pseudomonas putida LS46; biodiesel by-product streams; mcl-PHAs; medium-chain-length polyhydroxyalkanoates; polyhydroxyalcanoates à chaîne moyenne; produits dérivés du biodiesel