不同反胶束体系萃取纤维素酶的条件优化对比研究

采用3种不同的表面活性剂双(2-乙基己基)磺基琥珀酸钠AOT、十六烷基三甲基溴化铵CTAB及鼠李糖脂RL)溶于正己醇/异辛烷相构建不同的反胶束体系,并对比研究了不同反胶束体系萃取纤维素酶的优化条件.分别探讨了水相pH值、表面活性剂浓度、离子强度和离子种类对纤维素酶萃取效率的影响.实验结果如下:在实验条件下,AOT、CTAB和RL 3种反胶束体系水相最佳pH值分别为3.0、8.0和3.0;表面活性剂最佳浓度依次为:AOT 23.7mmol/L、CTAB 15mmol/L和RL 2.75mmol/L;水相中NaCl浓度会影响纤维素酶的萃取率,3种表面活性剂构建的反胶束体系萃取纤维素酶的萃取率均随着盐离子浓度的增大而降低;水相中离子种类也会影响纤维素酶的萃取率.比较不同反胶束体系在最佳条件下萃取纤维素酶的最佳萃取率:CTAB>AOT>RL.

Contrastive study on the optimization condition of cellulase extraction in different reverse micelles

Three surfactants, anioic docusate sodium salt (AOT),cationic cetylrimethylammonium bromide(CTAB) and anioic biosurfactant rhamnolipid(RL),were used to construct the reverse micelles system in (n-Hexanol/ 2,2,4-Trimethylpentane). The optimal extraction conditions of cellulase through different reverse micelles were studied. Several important parameters affecting the cellulase extraction efficiency were investigated, such as aqueous pH, surfactant concentration, ionic strength and salt species. It was shown that the optimal aqueous phase pH value for both AOT and RL extractants (anionic surfactant) was 3.0, while it was 8.0 for extractants of cationic surfactant CTAB. The optimal surfactant concentrations were 23.7mmol/L, 15mmol/L and 2.75mmol/L for AOT, CTAB and RL, respectively. Salt NaCl affected the extraction efficiency. For all the three surfactants, the extraction efficiency decreased with increase of NaCl concentration in aqueous phase. Moreover, ions species in the aqueous phase affected the extraction efficiency. The optimal extraction efficiency of cellulase varies with the type of reverse micelles (CTAB>AOT>RL).