title: Enhancing polyhydroxybutyrate production from high cell density fed-batch fermentation of Bacillus megaterium BA-019.
abstract: This study demonstrated the improved polyhydroxybutyrate (PHB) production via high cell density cultivation of Bacillus megaterium BA-019 with balanced initial total sugar concentration and carbon to nitrogen (C/N) weight ratio. In the 10 L stirred fermentor operated at 30 °C, pH 7.0, 600 rpm, and 1.0 vvm air, with the initial total sugar concentration of 60 g/L and urea at the C/N weight ratio of 10:1, 32.48 g/L cell biomass with the corresponding PHB weight content of 26.94 % and volumetric productivity of 0.73 g/L h were obtained from batch cultivation. Continuing cultivation by intermittent feeding of the sugarcane molasses along with urea at the C/N weight ratio of 12.5:1 gave much improved biomass and PHB production (90.71 g/L biomass with 45.84 % PHB content and 1.73 g/L h PHB productivity). Similar biomass and PHB yields were obtained in the 90 L stirred fermentor when using the impeller tip speed as the scale-up criterion.
authors: Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand.
authors: Pawut
authors: P
authors: Kanjanachumpol
authors: Songsri
authors: S
authors: Kulpreecha
authors: Vasana
authors: V
authors: Tolieng
authors: Nuttha
authors: N
authors: Thongchul
mesh_terms: D001410:Bacillus megaterium / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D018533:Biomass; D002244:Carbon / Q000378:metabolism; D005285:Fermentation; D006885:Hydroxybutyrates / Q000378:metabolism*; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000378:metabolism; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D031786:Saccharum / Q000378:metabolism
chemical_list: D006885:Hydroxybutyrates; D012336:RNA, Ribosomal, 16S; D002244:Carbon; D009584:Nitrogen