Producing poly-3-hydroxybutyrate with a high molecular mass from methane.
Poly-3-hydroxybutyrate (PHB) and other polyesters can be produced by various species of bacteria. Of the possible carbon sources, methane could provide a suitable substrate for the production of PHB. Methane is cheap and plentiful - not only as natural gas, but also as biogas. The methanotrophic strain Methylocystis sp. GB 25 DSMZ 7674 is able to accumulate PHB in a brief non-sterile process. The studies were carried out using a 7-l and a 70-l pressure bioreactor. Cultivation was performed in two stages: a continuous growth phase (dilution rate 0.17 h(-1)) and a PHB accumulation phase under deficiency conditions of an essential nutrient (ammonium, phosphorus or magnesium) in batch culture. The PHB content of biomass was as high as 51%; efficiency was highest during the first 5 h of the product formation process. The maximum PHB yield relative to the methane consumed was estimated to be 0.55 g g(-1). The PHB produced is of very high quality, having a high molecular mass of up to 2.5x10(6) Da.
Wendlandt
K D
KD
Department of Remediation Research, Centre for Environmental Research, Leipzig-Halle, P.O. Box 2, D-04301 Leipzig, Germany. wendland@san.ufz.de
Jechorek
M
M
Helm
J
J
Stottmeister
U
U
D020561:Alphaproteobacteria / Q000254:growth & development / Q000378:metabolism*; D018533:Biomass; D019149:Bioreactors; D002849:Chromatography, Gas; D003470:Culture Media; D006885:Hydroxybutyrates / Q000737:chemistry / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008697:Methane / Q000378:metabolism*; D008854:Microscopy, Electron; D015394:Molecular Structure; D008970:Molecular Weight; D011091:Polyesters / Q000737:chemistry / Q000378:metabolism*; D000094122:Polyhydroxybutyrates
D003470:Culture Media; D006885:Hydroxybutyrates; D008697:Methane; D011091:Polyesters; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates