Biosynthesis and Characterization of Poly(3-hydroxybutyrate-co-3- hydroxyhexanoate) from Palm Oil Products in a Wautersia eutropha Mutant

Palm kernel oil, palm olein, crude palm oil and palm acid oil were used for the synthesis of poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HHx)] by a mutant strain of Wautersia eutropha (formerly Ralstonia eutropha) harboring the Aeromonas caviae polyhydroxyalkanoate (PHA) synthase gene. Palm kernel oil was an excellent carbon source for the production of cell biomass and P(3HB-co-3HHx). About 87% (w/w) of the cell dry weight as P(3HB-co-3HHx) was obtained using 5 g palm kernel oil/l. Gravimetric and microscopic analyses further confirmed the high PHA content in the recombinant cells. The molar fraction of 3HHx remained constant at 5 mol % regardless of the type and concentration of palm oil products used. The small amount of 3HHx units was confirmed by 13C NMR analysis. The number average molecular weight (Mn) of the PHA copolymer produced from the various palm oil products ranged from 27 0000 to 46 0000 Da. The polydispersity was in the range of 2.6–3.9.

[1]  Alexander Steinbüchel,et al.  Perspectives for Biotechnological Production and Utilization of Biopolymers: Metabolic Engineering of Polyhydroxyalkanoate Biosynthesis Pathways as a Successful Example , 2001 .

[2]  Minoru Akiyama,et al.  Environmental life cycle comparison of polyhydroxyalkanoates produced from renewable carbon resources by bacterial fermentation , 2003 .

[3]  K. Sudesh,et al.  Synthesis, structure and properties of polyhydroxyalkanoates: biological polyesters , 2000 .

[4]  Y. Doi,et al.  Production of poly(3-hydroxybutyrate) from plant oils by Alcaligenes sp. , 1994 .

[5]  T. Fukui,et al.  Efficient production of polyhydroxyalkanoates from plant oils by Alcaligenes eutrophus and its recombinant strain , 1998, Applied Microbiology and Biotechnology.

[6]  S. Gan,et al.  Saponified palm kernel oil and its major free fatty acids as carbon substrates for the production of polyhydroxyalkanoates in Pseudomonas putida PGA1 , 1997, Applied Microbiology and Biotechnology.

[7]  H. Abe,et al.  Microbial synthesis and characterization of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) , 1995 .

[8]  A. Sinskey,et al.  Kinetic Studies of Polyhydroxybutyrate Granule Formation in Wautersia eutropha H16 by Transmission Electron Microscopy , 2005, Journal of bacteriology.

[9]  Prihardi Kahar,et al.  High yield production of polyhydroxyalkanoates from soybean oil by Ralstonia eutropha and its recombinant strain , 2004 .

[10]  Y. Doi.  Biodegradable Plastics and Polymers , 1994 .

[11]  McDowell Em,et al.  Histologic fixatives suitable for diagnostic light and electron microscopy. , 1976 .

[12]  H. Abe,et al.  Biosynthesis and properties of poly(3-hydroxybutyrate-co-3-hydroxyalkanoates) by recombinant strains of Pseudomonas sp. 61-3. , 2000, Biomacromolecules.

[13]  Y. Doi,et al.  Biosynthesis and compositional regulation of poly[(3-hydroxybutyrate)-co-(3-hydroxyhexanoate)] in recombinant ralstonia eutropha expressing mutated polyhydroxyalkanoate synthase genes. , 2004, Macromolecular bioscience.

[14]  A. Spurr.  A low-viscosity epoxy resin embedding medium for electron microscopy. , 1969, Journal of ultrastructure research.