Partitioning and extraction protease from Aspergillus tamarii URM4634 using PEG-citrate aqueous two-phase systems

Abstract

Abstract PEG-citrate Aqueous Two-Phase Systems (ATPS) were used to recover and partially purify protease from Aspergillus tamarii URM4634 produced by Solid State Fermentation. Experiments were performed according to a 2 4 -full factorial design using PEG molar mass ( M PEG ), PEG concentration ( C PEG ), citrate concentration ( C CIT ) and pH as independent variables; and purification factor ( PF ), partition coefficient ( K ) and activity yield ( Y ) as responses. Protease showed high activity in the PEG-rich phase, also M PEG and C CIT were shown to exert positive effects on all responses. The highest purification factor (3.95) was obtained using M PEG =8000 g/mol, 24% (w/w) C PEG , 20% (w/w) C CIT at pH 8.0. Consequently, the selected ATPS proved to be efficient and can be used as a first step for pre-purification of protease from solid state fermented of A. tamarii URM4634.