Partition Coefficient of Proteins of Different Surface Hydrophobicity in Poly (ethylene glycol)-Dextran Aqueous Two Phase System

Poly(ethylene glycol)-Dextran 수용액 2상계에서 단백질들의 소수성에 따른 분획계수

  • Lee, Sam-Pin (Department of Food Technology, Korea University) ;
  • Lee, Cherl-Ho (Department of Food Technology, Korea University)
  • 이삼빈 (고려대학교 식품공학과) ;
  • 이철호 (고려대학교 식품공학과)
  • Published : 1987.04.01


The partition coefficient of the proteins of known effective hydrophobicity was determined in a poly (ethylene glycol)-dextran aqueous two-phase system. The changes in the partition coefficient was also determined when a fraction of PEG-palmitate (PEG-P) was added to the system. The partition coefficient of the proteins increased as the concentrations of PEG and dextran increased at a constant phase volume ration irrespective of the effective hydrophobicity of the proteins. When small amounts of PEG-P were added to the PEG phase, the partition coefficients of BSA and ${\beta}-lactoglobulin$, which had relative hydrophobicity (RI) of 700 and 120, respectively, increased more than ten-fold, whereas ovalbumin whose RI was 5 showed little change. The drastic increases m the partition coefficient were observed by the addition of PEG-P in 2% level to the PEG system. Addition of PEG-P over 5% level resulted in a slight further increase in the partition coefficient of all proteins tested.