Parameters influencing protein extraction for whole broths in detergent based aqueous two-phase systems

Research output: Contribution to journalArticle


The parameters important for an optimisation of cloud point extraction in technical scale were investigated using a genetically engineered fusion protein derived from endoglucanase I expressed in Trichoderma reesei and the nonionic polyoxyethylene Agrimul NRE 1205. The key parameters are temperature, detergent concentration, and additional salts. These parameters are interdependent, thus there is an optimum in the partition coefficient with respect to detergent concentration and a maximum for the partition coefficient and the yield with respect to temperature. These results were confirmed for the detergent C12E5 to demonstrate that these optima are due to the nature of polyoxyethylenes. Cloud point extraction was found to be only slightly affected by pH. In the case studied extraction of whole broth is favourable for a high yield and partition coefficient, since fusion protein adhering to the cells can be solubilized. However some loss of detergent which remains in the fungal biomass was observed.


  • Klaus Selber
  • Anna Collén
  • Teppo Hyytia
  • Merja Penttila
  • Folke Tjerneld
  • Maria-Regina Kula
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Biological Sciences


  • aqueous two-phase systems, detergent-based systems, protein extraction, protein purificaton, cloud-point extraction
Original languageEnglish
Pages (from-to)229-236
Issue number4-5
Publication statusPublished - 2002
Publication categoryResearch