Dependence of chymosin and pepsin partition coefficient with phase volume and polymer pausidispersity in polyethyleneglycol–phosphate aqueous two-phase system

The influence of the phase volume ratio and polymer pausidispersity on chymosin and pepsin partition in polyethylenglycol–phosphate aqueous two-phase systems was studied. Both proteins showed a high affinity for the polyethylenglycol rich phase with a partition coefficient from 20 to 100 for chymosin and from 20 to 180 for pepsin, when the polyethyleneglycol molecular mass in the system varied between 1450 and 8000. The partition coefficient of chymosin was not affected by the volume phase ratio, while the pepsin coefficient showed a significant decrease in its partition coefficient with the increase in the top/bottom phase volume ratio.