The protease from Aspergillus tamarii Kita UCP1279 extraction by aqueous two-phase PEG-Citrate (ATPS) systems, using a factorial design 2⁴, was investigated. Then, the variables studied were polyethylene glycol (PEG) molar mass (M_PEG), concentrations of PEG (C_PEG) and citrate (C_CIT), and pH. The responses analyzed were the partition coefficient (K), activity yield (Y) and purification factor (PF). The thermodynamic parameters of the ATPS partition were estimated as a function of temperature. ATPS was able to pre-purify the protease (PF = 1.6) and obtained 84% activity yield. The thermodynamic parameters ΔG°_m (−10.89 kJ mol⁻¹), ΔH_m (−5.0 kJ mol⁻¹) and partition ΔS_m (19.74 J mol⁻¹ K⁻¹) showed that the preferential migration of almost all protein contaminants of the crude extract to the salt-rich phase, while the preferred protease was the PEG rich phase. The extracted enzyme presents optimum temperature and pH at range of 40–50 °C and 9.0–11.0, respectively. Moreover, the enzyme was identified as serine protease based on inhibition profile. ATPS showed the satisfactory performance as the first step for Aspergillus tamarii Kita UCP1279 protease pre-purification.

使用析因设计2 ⁴，研究了由水相两阶段PEG-柠檬酸盐（ATPS）系统提取的塔玛曲霉Kita UCP1279蛋白酶。然后，研究的变量是聚乙二醇（PEG）摩尔质量（M _PEG），PEG（C _PEG）和柠檬酸盐（C _CIT）的浓度以及pH值。分析的响应是分配系数（K），活性产率（Y）和纯化因子（PF）。估计ATPS分区的热力学参数是温度的函数。ATPS能够预纯化蛋白酶（PF = 1.6），并获得84％的活性产率。热力学参数ΔG°_米（-10.89千焦摩尔^-1），ΔH_米（-5.0千焦摩尔^-1）和分区ΔS_米（19.74摩尔Ĵ ^-1 ķ ^-1）表明，粗提物的富盐相的几乎所有的蛋白污染物的优先迁移，而优选的蛋白酶是PEG丰富阶段。提取的酶分别在40–50°C和9.0–11.0的范围内具有最佳温度和pH值。此外，基于抑制谱，该酶被鉴定为丝氨酸蛋白酶。ATPS显示出令人满意的性能，它是塔玛曲霉Kita UCP1279蛋白酶预纯化的第一步。