Measurement of partition coefficients of β-amylase and amyloglucosidase enzymes in aqueous two-phase systems containing poly(ethylene glycol) and Na2SO4/KH2PO4 at different temperatures

In this research, partitioning of β-amylase and amyloglucosidase was investigated in polymer–salt aqueous two-phase systems containing poly(ethylene glycol) (PEG) with different molecular weights such as 4000, 6000 and 10,000 and Na2SO4 or KH2PO4. The experimental partition coefficients were measured at T = (298.5, 301.5, 303.5, 305.5 and 308) K. The results showed that the concentration of salt in feed had more effect on partition coefficients of β-amylase and amyloglucosidase in aqueous two-phase systems than the concentration of polymer in initial feed. Also, the results indicated that temperature had a small effect on partitioning of β-amylase and amyloglucosidase enzymes. The partition coefficients of β-amylase and amyloglucosidase in polymer–salt aqueous two-phase systems were correlated using the UNIFAC-FV group contribution model.