MEASUREMENT AND CORRELATION OF PARTITION COEFFICIENTS OF UROKINASE IN AQUEOUS TWO-PHASE PEG-POTASSIUM PHOSPHATE SYSTEM

Partition coefficients of Urokinase(UK)were measured in aqueous two-phase systems con-taining polyethylene glycol and potassium phosphate at 273.2K.Based on the Diamond-Hsu model,a modified expression was obtained for the correlation of enzyme partitioning in theabove-mentioned systems.Utilizing a modified form,the partitioning data of UK and heteroproteinwere correlated.The results show that the modified model is simple gives good precision.and will fa-cilitate engineering scale-up of aqueous two-phase systems for certain proteins purification.     

青霉素发酵液中可溶性蛋白质的沉降及其在溶剂萃取中的乳化作用

利用自合成的阴离子型共聚物研究了青霉素发酵液中可溶性蛋白质的沉降行为．同时考察了发酵液中部分蛋白质被除去后,液液萃取过程中乳化程度的变化情况．实验结果表明,含反应性官能团的高分子共聚物能有效地除去青霉素发酵液中的蛋白质,减轻液液萃取过程中的乳化程度,从而提高青霉素的提取率,同时减少废渣的产生．高分子共聚物的组成对发酵液中蛋白质的沉降和有机相破乳有很大的影响．     

用双水相系统释放大肠杆菌L-天门冬酰胺酶

引　言Ｌ 天门冬酰胺酶 (ＥＣ3 5 1 1)能催化Ｌ 天门冬酰胺水解为Ｌ 天门冬氨酸和氨 ,是治疗白血病的药物 .目前Ｌ 天门冬酰胺酶主要由微生物发酵生产 ,属于胞内酶 .传统的提取纯化Ｌ 天门冬酰胺酶的过程包括制备丙酮粉和缓冲液萃取[1] .这种方法要使用大量的丙酮 ,产生细胞碎     

双水相分配结合温度诱导相分离从酵母中提取谷胱甘肽

对用双水相分配技术结合温度诱导相分离技术从酵母中提取谷胱甘肽（GSH）进行了研究．考察了GSH在环氧乙烷──环氧丙烷无规共聚物（EOPO）／羟丙基淀粉（PES）系统中的分配行为,包括两次分离过程（双水相分配及温度诱导过程)中的不同系统组成、pH等对GSH分配的影响,确定了较佳的双水相系统──EOPO400013％,PES10010％,pH=10.5．在此基础上进行了从酵母细胞中提取GSH的工艺研究,设计了合理的分离流程,研究结果表明GSH的总萃取率可达80％以上．     

醇对正负离子表面活性剂双水相性质的影响

The effect of alcohol on the aqueous two-phase system properties of SDS/CTAB/H2O/Na2SO4 system was studied by the pseudo ternary phase diagram. The electrostatic forces (both attraction and repulsion) between cationic surfactant and anionic surfactant decreased because of the interaction of alcohol hydroxyl group and surfactant polar group. As a result, the phase area width of aqueous two-phase system increased. Long chain alcohol (more than five carbonatoms), which was in high concentration in the SDS/CTAB/H2O/Na2SO4) system, caused the anionic aqueous two-phase system area to vanish and the cationic aqueous two-phase system area to become wider. The CTAB rich phase turned from top phase to bottom phase.     

蛋白质-磷酸钾-聚乙二醇双水相体系热力学研究

建立了由蛋白质、磷酸氢二钾、磷酸二氢钾、聚乙二醇所组成的双水相体系的平衡浓度分析测定方法,实验测定了6种蛋白质分子在25℃下的液液平衡分配数据,共23组.将Baskir等的吸附晶格模型和Pitzer的长程静电项相结合,扩展用于含电解质-高聚物双水相体系的热力学计算,仅用7组实验数据进行关联,得到2个吸附能参数,预测了其它16组蛋白质分配系数,结果满意。并提出了蛋白质分配系数与双水相成相物质在两相间浓度差的经验关系式。     

THE SEPARATION OF ALUMINUM FROM AN ALKALINE SOLUTION CONTAINING MOLYBDENUM AND VANADIUM BY EXTRACTION WITH LIX 26 DISSOLVED IN n-OCTANOL / HEXANE MIXTURES

The alkalyne leaching of spent alumina-based catalysts from the petroleum industry, containing molybdenum and/or vanadium among other metals, yields a solution rich in Mo(VI), V(V) and Al(III). In order to recover the two heavy metals aluminum must be first quantitatively separated. Several routes were theoretically tested by computer simulation. Finally, the extraction of aluminum with oxine was chosen. A commercial reagent similar to oxime, LIX 26 (Henkel), was used. The extraction of the three metals with several organic phases containing LIX 26 /n-octanol /hexane was systematically studied.|The best separation conditions were found to be 7<pH<8, 0.3% LIX 26 and 10% n-octanol. A two step counter-current extraction with equal volumes of the two phases gives 99.6% extraction of Al(III) with less than 1 ppm of Mo(VI) and V(V). The organic phase can be regenerated by contacting with sulphuric acid, at pH<2, where aluminum is quantitatively stripped.