Shin Youn-Ok, Vera Juan H
Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, Quebec, Canada, H3A 2B2.
Biotechnol Bioeng. 2002 Dec 5;80(5):537-43. doi: 10.1002/bit.10413.
Dioctyldimethyl ammonium chloride (DODMAC) was used to form reverse micelles and to extract lysozyme from an aqueous solution into an organic phase. The solubilization behavior of lysozyme into a DODMAC reverse micellar phase was examined in terms of the temperature, the type of cations in the aqueous phase, and the surfactant concentration in the organic phase. Complete removal of lysozyme from the aqueous phase was obtained when the pH was set one unit higher than the pI of the protein. However, it was found that there is a solubilization limit of lysozyme in the organic phase. Not all the lysozyme extracted out of the initial aqueous phase was solubilized into the DODMAC reverse micellar phase, resulting in the formation of white precipitate at the aqueous-organic interface. Temperature has a negligible effect on the solubilization limit of lysozyme. The value of the solubilization limit is a strong function of the type of cations present in the aqueous phase, indicating an important role of lysozyme-cation interactions on the extraction process. An increase in the DODMAC concentration from 100-200 mM resulted in little change in the highest concentration of lysozyme obtained in the organic phase.
二辛基二甲基氯化铵（DODMAC）被用于形成反胶束，并将溶菌酶从水溶液中萃取到有机相中。从温度、水相中阳离子的类型以及有机相中表面活性剂的浓度等方面考察了溶菌酶在DODMAC反胶束相中的增溶行为。当pH值设定为比蛋白质的pI高一个单位时，可实现从水相中完全去除溶菌酶。然而，发现溶菌酶在有机相中有一个增溶极限。并非所有从初始水相中萃取出来的溶菌酶都能增溶到DODMAC反胶束相中，导致在水-有机界面处形成白色沉淀。温度对溶菌酶的增溶极限影响可忽略不计。增溶极限的值强烈依赖于水相中存在的阳离子类型，表明溶菌酶-阳离子相互作用在萃取过程中起着重要作用。将DODMAC浓度从100 - 200 mM提高，有机相中获得的溶菌酶最高浓度变化不大。
