Cell debris removal

The initial processing steps are determined to a large extent by the location of the product species, and they generally consist of cell/broth separation and/or cell debris removal. For products retained within the biomass during production, it is first necessary to concentrate the cell suspension before homogenization or chemical treatment to release the product. Clarification to remove the suspended solids is the process goal at this stage. 

The cells obtained from 1 L of culmre medium were harvested, disrupted by sonication and cell debris removed by centrifugation. 

Removal of the debris produced by mechanical disruption can be improved if the particle diameter is increased. This can be done either by flocculation, coagulation or by binding to the various chemical bioprocessing aids such as polyvinylpyrrlidone, Whatman CDR (cell debris remover), chitosan or Biocryl bioprocessing aids (BPAS). The adsorbed materials can be removed by filtration or centrifugation. 

Datar RV, Rosen C-G (1996) Cell and cell debris removal centrifugation and crossflow filtration. In Stephanopoulos G (ed) Bioprocessing. VCH, Weinheim, p 472... 

Environmental Control Cell Disruption and Cell debris Removal... 

Aqueous two-phase extraction is the most promising operation for cell debris removal that, despite its potential for protein fractionation (Marcos et al. 1999 ... 

When used for cell debris removal, proteins invariably concentrate in the top phase (PEG in the case of PEG/dextran and PEG/salt), while fragments do it in the bottom phase. Therefore yield of protein recovery is ... 

Since propionibacteria are approved for use in food industry, die following simple preparation can be recommended for this purpose. After the extraction of vitamin Bn with 20% ethanol, the biomass is disintegrated and cell debris removed by filtration the filtrate contains catalase, peroxidase and SOD activities and can be used as an antioxidant preparation without further purification. 

Disc stack, decanter and tubular bowl centrifuges are used for a wide range of separation duties in the pharmaceutical and fermentation industries, including liquid-solid, liquid-liquid, liquid-liquid-soUd separations, and liquid-solid extraction. Typical process steps include cell harvesting, concentration and washing, cell debris removal, inclusion body recovery and purification, solvent extraction, dewatering and recovery. 

---