Xie Wenlei, Zang Xuezhen
School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450001, PR China.
School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450001, PR China.
Food Chem. 2016 Mar 1;194:1283-92. doi: 10.1016/j.foodchem.2015.09.009. Epub 2015 Sep 6.
A core-shell structured Fe3O4-MCM-41 nanocomposite was prepared by means of a surfactant-directed sol-gel process. Candida rugosa lipase was then bound to the magnetic core-shell material by using glutaraldehyde as a cross-linking reagent. The as-prepared Fe3O4-MCM-41 support and the immobilized lipase were characterized in detail using enzyme activity assays, TEM, XRD, FTIR, VSM and nitrogen adsorption-desorption techniques. Results showed that the magnetite nanoparticles were coated with the MCM-41 silica with the formation of core-shell structured materials, and the lipase was successfully immobilized on the core-shell structured support. The catalytic performance of the bound lipase was tested in the interesterification of lard and soybean oil. It was shown that the immobilized lipase had a better catalytic activity towards the interesterification reaction. The slip melting point of the final product was lower than that of the original blend, and the interesterification led to an obvious variation in the microstructure of the product.
通过表面活性剂导向的溶胶-凝胶法制备了核壳结构的Fe3O4-MCM-41纳米复合材料。然后使用戊二醛作为交联剂将皱褶假丝酵母脂肪酶结合到磁性核壳材料上。利用酶活性测定、透射电子显微镜（TEM）、X射线衍射（XRD）、傅里叶变换红外光谱（FTIR）、振动样品磁强计（VSM）和氮吸附-脱附技术对所制备的Fe3O4-MCM-41载体和固定化脂肪酶进行了详细表征。结果表明，磁铁矿纳米颗粒被MCM-41二氧化硅包覆，形成了核壳结构材料，脂肪酶成功固定在核壳结构载体上。在猪油和大豆油的酯交换反应中测试了固定化脂肪酶的催化性能。结果表明，固定化脂肪酶对酯交换反应具有较好的催化活性。最终产物的滑动熔点低于原始混合物，酯交换导致产物微观结构发生明显变化。
