- Autor
- Lambauer, Vera
- Kratzer, Regina
- TitelLab-Scale Cultivation of Cupriavidus necator on Explosive Gas Mixtures: Carbon Dioxide Fixation into Polyhydroxybutyrate
- Datei
- DOI10.3390/bioengineering9050204
- Erschienen inBioengineering
- Band9
- Erscheinungsjahr2022
- Heft5
- LicenceCC BY 4.0
- ISSN2306-5354
- Download Statistik948
- Peer ReviewJa
- AbstractAerobic, hydrogen oxidizing bacteria are capable of efficient, non-phototrophic CO2 assimilation, using H2 as a reducing agent. The presence of explosive gas mixtures requires strict safety measures for bioreactor and process design. Here, we report a simplified, reproducible, and safe cultivation method to produce Cupriavidus necator H16 on a gram scale. Conditions for long-term strain maintenance and mineral media composition were optimized. Cultivations on the gaseous substrates H2, O2, and CO2 were accomplished in an explosion-proof bioreactor situated in a strong, grounded fume hood. Cells grew under O2 control and H2 and CO2 excess. The starting gas mixture was H2:CO2:O2 in a ratio of 85:10:2 (partial pressure of O2 0.02 atm). Dissolved oxygen was measured online and was kept below 1.6 mg/L by a stepwise increase of the O2 supply. Use of gas compositions within the explosion limits of oxyhydrogen facilitated production of 13.1 ± 0.4 g/L total biomass (gram cell dry mass) with a content of 79 ± 2% poly-(R)-3-hydroxybutyrate in a simple cultivation set-up with dissolved oxygen as the single controlled parameter. Approximately 98% of the obtained PHB was formed from CO2.