Establishing a Fed-Batch Process for Protease Expression with Bacillus licheniformis in Polymer-Based...

Area of Science:

• Biotechnology
• Microbial Fermentation
• Process Development

Background:

• Industrial fed-batch fermentation requires comparable small-scale models for early development.
• Existing laboratory equipment needs cost-efficient, easy-to-use fed-batch systems.
• A novel polymer-based controlled-release fed-batch microtiter plate offers a potential solution.

Purpose of the Study:

• To investigate fed-batch cultivations of protease-producing Bacillus licheniformis using the novel microtiter plate.
• To assess the reproducibility and scalability of the system.
• To establish and validate a mechanistic model for small-scale fed-batch cultivations.

Main Methods:

• Utilized a polymer-based controlled-release fed-batch microtiter plate for Bacillus licheniformis cultivations.
• Online monitoring of oxygen transfer rate (OTR) using a µRAMOS device.
• Investigated effects of initial biomass, filling volume, and osmotic pressure on fermentation performance.

Main Results:

• Demonstrated good reproducibility (CV of 9.2%) across multiple plates and production lots.
• Identified key parameters influencing batch/fed-batch phase duration and OTR.
• Established volumetric glucose release rate as a valid scale-up criterion for comparability between microtiter plate and shake flask systems.

Conclusions:

• The polymer-based fed-batch microtiter plate is a reproducible and effective tool for small-scale fermentation development.
• The system facilitates comparable conditions to industrial processes, aiding scale-up.
• A validated mechanistic model supports process understanding and simulation based on small-scale data.