In bacterial and other cell cultures where the goal is to retain biomass for stock or downstream processing, a variety of factors during harvest and separation may impact yield and quality, especially in concentrated cultures. For example, reduced biomass quantity can occur in filter-based separation methods due to clogs and membrane fouling, while continuous and most batch centrifugation separation methods expose the culture to risks of contamination from the surrounding environment.
At the same time, freezing collected biomass in bottles for later use takes up valuable space in freezers – especially if the bottles are only partially filled.
Use of sterilized, single-use Thermo Scientific™ CentriPAK™ BioProcess Containers (BPC) and the Thermo Scientific™ Sorvall™ BIOS 16 Centrifuge is an excellent method to achieve maximum biomass recovery while using minimal freezer storage space. The nature of batch centrifugation eliminates the risks of clogs and fouling and this closed-system method also avoids contamination risks that could negatively impact yield. Additionally, cell pellets may be stored directly in the flexible CentriPAK BPC chamber to save significant freezer space. In this example, we harvest biomass from a 30 L fermentation culture.