title: Production of poly-beta-hydroxybutyrate (PHB) by Alcaligenes latus from maple sap.
abstract: Maple sap, an abundant natural product especially in Canada, is rich in sucrose and thus may represent an ideal renewable feedstock for the production of a wide variety of value-added products. In the present study, maple sap or sucrose was employed as a carbon source to Alcaligenes latus for the production of poly-beta-hydroxybutyrate (PHB). In shake flasks, the biomass obtained from both the sap and sucrose were 4.4 +/- 0.5 and 2.9 +/- 0.3 g/L, and the PHB contents were 77.6 +/- 1.5 and 74.1 +/- 2.0%, respectively. Subsequent batch fermentation (10 L sap) resulted in the formation of 4.2 +/- 0.3 g/L biomass and a PHB content of 77.0 +/- 2.6%. The number average molecular weights of the PHB produced by A. latus from maple sap and pure sucrose media were 300 +/- 66 x 10(3) and 313 +/- 104 x 10(3) g/mol, respectively. Near-infrared, (1)H magnetic resonance imaging (MRI), and (13)C-MRI spectra of the microbially produced PHB completely matched those obtained with a reference material of poly[(R)-3-hydroxybutyric acid]. The polymer was found to be optically active with [alpha](25) (D) equaled to -7.87 in chloroform. The melting point (177.0 degrees C) and enthalpy of fusion (77.2 J/g) of the polymer were also in line with those reported, i.e., 177 degrees C and 81 J/g, respectively.
authors.affiliation: Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, QC, H4P 2R2, Canada.
authors.forename: Abdessalem
authors.initials: A
authors.lastname: Yezza
authors.forename: Annamaria
authors.initials: A
authors.lastname: Halasz
authors.forename: Wayne
authors.initials: W
authors.lastname: Levadoux
authors.forename: Jalal
authors.initials: J
authors.lastname: Hawari
mesh_terms: D031002:Acer / Q000737:chemistry*; D000421:Alcaligenes / Q000254:growth & development / Q000378:metabolism*; D003470:Culture Media; D005285:Fermentation; D006885:Hydroxybutyrates / Q000737:chemistry / Q000378:metabolism*; D007218:Industrial Microbiology / Q000379:methods; D008279:Magnetic Resonance Imaging; D011091:Polyesters / Q000737:chemistry / Q000378:metabolism*; D013395:Sucrose / Q000378:metabolism*; D000094122:Polyhydroxybutyrates
chemical_list: D003470:Culture Media; D006885:Hydroxybutyrates; D011091:Polyesters; D013395:Sucrose; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates