Production of poly-beta-hydroxybutyrate (PHB) by Alcaligenes latus from maple sap.
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.
Yezza
Abdessalem
A
Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, QC, H4P 2R2, Canada.
Halasz
Annamaria
A
Levadoux
Wayne
W
Hawari
Jalal
J
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
D003470:Culture Media; D006885:Hydroxybutyrates; D011091:Polyesters; D013395:Sucrose; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates