Poly(3-Hydroxybutyrate) Production in Repeated fed-Batch with Cell Recycle Using a Medium with low Carbon Source...

Area of Science:

• Biotechnology
• Microbial Engineering
• Polymer Science

Background:

• Low-cost substrates in bioprocesses often have low carbon concentrations, hindering productivity.
• Real-time control of intracellular product formation in bioprocesses presents significant challenges.

Purpose of the Study:

• To develop a strategy for high cell density and poly(3-hydroxybutyrate) (P(3HB)) productivity in Cupriavidus necator using low-carbon substrates.
• To implement an online process control method for intracellular products using oxygen uptake rate (OUR) data.

Main Methods:

• Employing a repeated fed-batch cultivation with cell recycle for Cupriavidus necator.
• Utilizing a substrate with a low carbon source concentration (90 g/l).
• Monitoring oxygen uptake rate (OUR) for real-time process control.

Main Results:

• Achieved a total biomass (X) of 61.6 g/l and residual biomass (Xr) of 19.3 g/l.
• Obtained 42.4 g/l of poly(3-hydroxybutyrate) (P(3HB)), representing 68.8% of cell content.
• Reached a P(3HB) productivity of 1.0 g/l/h.

Conclusions:

• The proposed strategy is effective for high cell density and high P(3HB) content production.
• This method enables efficient bioprocessing even with low carbon source concentrations.
• Online OUR monitoring provides a viable solution for controlling intracellular product formation.