Department of Biochemistry, Selcuk University, 42075 Konya, Turkey.
Department of Biochemistry, Selcuk University, 42075 Konya, Turkey.
Int J Biol Macromol. 2021 Apr 1;175:79-86. doi: 10.1016/j.ijbiomac.2021.02.003. Epub 2021 Feb 4.
Metal organic frameworks (MOFs) are hybrid organic inorganic materials with unique properties such as well-defined pore structure, extremely high surface area, excellent chemical-thermal stability. MOFs-based constructs have been extensively engineered and used for applications, such as enzyme immobilization for bio-catalysis. To obtained a zeolitic imidazole framework-8 (ZIF-8) for enzyme immobilization, Candida rugosa lipase (CRL) was pretreated with calix [4]arene tetracarboxylic acid (Calix) and reacted with Zn and imidazole by co-precipitation method. The prepared biocomposite was characterized by SEM, EDX, FT-IR, and XRD. The prepared CRL@Calix-ZIF-8 with high encapsulation efficiency showed improved resistance to alkali and thermal conditions. The CRL@Calix-ZIF-8 with the biocatalytic activity was 2-folds higher than that of the CRL@ZIF-8 (without Calix). The free lipase lost its catalytic activity completely at 60 °C after 100 min, while the CRL@Calix-ZIF-8 and CRL@ZIF-8 retained about 84% and 73%. It was found that CRL@Calix-ZIF-8 and CRL@ZIF-8 still retained ~83 and 67% of catalytic activity after its 6th use, respectively. The kinetic resolution of the immobilized lipases was examined for enantioselective hydrolysis of racemic naproxen methyl ester. CRL@Calix-ZIF-8 showed enantioselectivity against the racemic naproxen methyl ester, with E = 183 and 131 compared to the CRL@ZIF-8.
金属有机骨架（MOFs）是一种具有独特性质的混合有机-无机材料，具有明确的孔结构、极高的比表面积、优异的化学-热稳定性。基于 MOFs 的构建物已被广泛设计和用于各种应用，例如酶固定化用于生物催化。为了获得用于酶固定化的沸石咪唑酯骨架-8（ZIF-8），采用杯[4]芳烃四羧酸（Calix）对里氏木霉脂肪酶（CRL）进行预处理，然后通过共沉淀法与 Zn 和咪唑反应。通过 SEM、EDX、FT-IR 和 XRD 对制备的生物复合材料进行了表征。制备的具有高包封效率的 CRL@Calix-ZIF-8 显示出对碱和热条件的改善抗性。与没有 Calix 的 CRL@ZIF-8 相比，具有生物催化活性的 CRL@Calix-ZIF-8 高出 2 倍。游离脂肪酶在 60°C 下 100 分钟后完全失去催化活性，而 CRL@Calix-ZIF-8 和 CRL@ZIF-8 保留了约 84%和 73%。结果发现，CRL@Calix-ZIF-8 和 CRL@ZIF-8 在第 6 次使用后分别仍保留约 83%和 67%的催化活性。固定化脂肪酶的动力学拆分用于对映选择性水解外消旋萘普生甲酯。CRL@Calix-ZIF-8 对消旋萘普生甲酯表现出对映选择性，E 值分别为 183 和 131，而 CRL@ZIF-8 的 E 值为 110。
