S49: Automated on-line sampling and nutrient monitoring: a solution for optimizing fed-batch culture performance

A SegFlow® automated on-line sampling and nutrient monitoring system (SegFlow System) was used to evaluate and optimize fed-batch culture performance of standard and genetically modified strains of Scarab Genomics’ Clean Genome® E. coli.  The evaluated strains were used for the biotherapeutic production of a single chain antibody and a well tolerated soluble protein.  Standard fermentation conditions were conducted at 10L working volume using a mineral salts batch medium.  The cultivation temperature was maintained at 37°C throughout the process duration.  Glucose was fed exponentially to control the culture growth rate at a specified constant µ hr^-1.  Success criteria were based on performance metrics such as biomass production, volumetric yield and protein solubility  The SegFlow System, consisting of an autosampler control module, a fraction collector and a biochemistry analyzer, provided real-time analysis of media glucose concentrations as well as programmed time-point sampling for additional off-line analytics.  Real-time media glucose concentration monitoring provided a means for characterizing the culture’s glucose utilization profile and to assay the effects of genetic modifications.  An optimized feeding strategy was implemented to better meet culture glucose uptake requirements, which resulted in improved culture performance and consistency.   The SegFlow System provided an innovative approach for optimizing E. coli fed-batch process performance through better process monitoring and control, while increasing process knowledge and understanding through real-time sample analysis.