Design and evaluation of a two-stage, cyclic, recombinant fermentation process.

Area of Science:

• Biotechnology
• Microbial Fermentation
• Genetic Engineering

Background:

• Recombinant protein production is crucial for therapeutics.
• Escherichia coli is a common host for recombinant protein synthesis.
• Optimizing fermentation processes is key to improving yield and efficiency.

Purpose of the Study:

• To design and evaluate a two-stage, cyclic fed-batch fermentation process.
• To enhance the production of recombinant human lymphokine.
• To improve volumetric productivity in microbial fermentation.

Main Methods:

• Utilized Escherichia coli K-12 with a temperature-sensitive plasmid for lymphokine production.
• Implemented a two-stage fed-batch system: a growth stage at 28°C and an induction stage at 42°C.
• Employed a cyclic process with repeated transfers to maximize cell density and product formation.

Main Results:

• Achieved consistent high cell density (OD(600) > 100) in the induction stage.
• Completed 30 cycles with stable lymphokine yield and cell density.
• Produced 200 L of material from the first stage in 10 days.
• Demonstrated a two-fold increase in volumetric productivity compared to single-stage processes.

Conclusions:

• The two-stage, cyclic fed-batch process is effective for high-yield recombinant human lymphokine production.
• This method offers significant improvements in volumetric productivity and process efficiency.
• The designed bioprocess is scalable and robust for industrial applications.