Harvesting recombinant microbial cells using crossflow filtration.

Area of Science:

• Biotechnology and Bioprocessing
• Separation Science
• Microbial Cell Harvesting

Background:

• Traditional cell harvesting methods can be time-consuming and inefficient for large-scale microbial fermentations.
• Recombinant Saccharomyces cerevisiae and Escherichia coli are widely used in biopharmaceutical production, necessitating effective downstream processing.

Purpose of the Study:

• To evaluate the efficacy of a contained, crossflow filtration (CFF) membrane system for harvesting and diafiltering microbial cells.
• To assess the performance of CFF across various cell densities (low and high) and volumes for S. cerevisiae and E. coli.

Main Methods:

• Utilized a portable, clean-in-place (CIP) compatible CFF system with hollow fiber or flat sheet membranes.
• Harvested and diafiltered recombinant S. cerevisiae and E. coli from fermentation volumes ranging from 10 to 200 liters.
• Operated the system with both low-cell density (LCD) and high-cell density (HCD) fermentation broths.

Main Results:

• Achieved cell harvesting and diafiltration times under 2.5 hours for all tested conditions.
• Successfully processed S. cerevisiae fermentations up to 63 g/L dry weight (dcw) and E. coli up to 16.2 g/L dcw.
• Demonstrated efficient performance with varying membrane areas (14 to 75 ft2) for different fermentation types.

Conclusions:

• Contained, crossflow filtration (CFF) is a highly efficient and rapid method for harvesting and diafiltering recombinant S. cerevisiae and E. coli.
• The CFF system's portability and in-place cleanability make it suitable for diverse bioprocessing scales and applications.