Improving Extraction Of Intracellular L-Asparaginase By High Pressure Homogenization Integrated With Aqueous Two-phase Extraction System

L-asparaginase( EC 3.5.1.1), an effective antileukemia agent, has been used in clinical treatment. The effect of high pressure homogenization (HPH) on the primary extraction of intracellular L-asparaginase from E.Coli integrated with aqueous two-phase extraction (ATPE) has been investigated. When HPH was operated under the pressure of 120 MPa for four passages, 17.8% of L-asparaginase activity was lost. The addition of EOPO (a triblock copolymer of a central hydrophobic poly(propylene oxide) (PPO) block with hydrophilic poly(ethylene oxide) (PEO) blocks on each side) could improve the endurance of L-asparaginase to high pressure; while the existence of KHP (the mixture of KH₂PO₄ and K₂HPO₄) could strongly facilitate such deactivation. When HPH was operated in ATPE system formed from EOPO and KHP, the recovery of L-asparaginase was greatly enhanced, as compared to the conventional HPH process.