As seen in Table 2, increase in amm

As seen in Table 2, increase in ammonium sulfate concentration used to make the two-phase system increased only the recovery of papain in the top phase but not that of total protease activity. On the other hand, PEG concentration did not have any significant effect on protease partitioning in general. Partitioning at protein concentrations ranging between 10 and 40 mg protein/ml in 12% PEG–15% (NH4)2SO4 revealed no notable variation in protease partition to the top phase. A significant decrease in partition was indeed observed at higher protein concentrations (60 mg/ml and above) probably due to the limiting solvating effect of PEG.