Study on partition of α- lactalbumin and β- lactoglobulin with PVP/K_2HPO_4 aqueous two- phase systems

In the present study,the partitioning of α- LA and β- LG in aqueous two- phase system of polyvinylpyrrolidone- potassium phosphate was investigated.The partitioning of proteins in this system depends on PVP molecular weight,the polymer,salt weight percents,p H and temperature was used to study the effects of different parameters on partitioning of α- LA and β- LG.The optimum conditions of distribution of α- LA and β- LG were 16%( w / w) and 14%( w / w) of the amount of PVP weight percent 10000 u and K_2HPO_4 separately,temperature for 30 ℃,and p H7.5.Results indicated that α- LA and β- LG were assigned in the phase of the upper and the bottom of the aqueous two- phase system respectively.The corresponding partition coefficients were 7.32 and 0.38,and the rate of partition were 88.29% and 74.07% according to the partition of α- LA and β- LG.