ZIF-F原位合成法固定化木瓜蛋白酶  

Immobilization of Papain by ZIF-F in Situ Synthesis

作　　者：徐云涛 谢毅鹏 王车礼[1] XU Yuntao;XIE Yipeng;WANG Cheli(Lab.of High Quality Utilization of Natural Extracted Drugs and Medicinal Materials Resources,School of Pharmacy,Changzhou University,Changzhou 213164,Chin)

机构地区：[1]常州大学药学院,天然药物提取与药材资源高质利用实验室,江苏常州213164

出　　处：《食品科技》2022年第11期10-16,共7页Food Science and Technology

基　　金：江苏省教育厅面上项目(19KJB480004);江苏省研究生科研与实践创新计划项目(SJCX21-1291)。

摘　　要：文章以新型ZIF-F为固定化载体,通过原位合成法固定木瓜蛋白酶,制备得到新型固定化酶Papain@ZIF-F,并采用傅里叶红外光谱、X射线衍射图谱、扫描电镜、BET比表面积分析、热重分析进行表征。此外,还制备了以ZIF-8为基质原位合成的Papain@ZIF-8并与Papain@ZIF-F在形貌结构及比活性、稳定性等方面进行对比。表征结果证明,木瓜蛋白酶被包埋于ZIF骨架中且酶的加入并未影响到ZIF骨架的结构特性,且采用ZIF-F包埋的酶粒径可达2μm,远超ZIF-8的500nm,这可能是因为ZIF-F合成过程中加入2-甲基咪唑量较少导致晶体生长较慢,颗粒尺寸偏大。比活性方面,Papain@ZIF-F的比活性较游离酶及Papain@ZIF-8均有显著提升,最高可达390 U/mg,较游离酶比活性提升了约200%。这可能是因为ZIF-F具有更大的比表面积,使其对底物的阻力更小从而有利于酶与底物充分接触,进而导致比活性提高。最后,Papain@ZIF-F在重复使用5次后活性仍高于游离酶,重复使用情况良好。In this study,papain was immobilized by in-situ synthesis with a new ZIF-F as the immobilization carrier,a novel immobilized enzyme was prepared,papain@ZIF-F was characterized by Fourier infrared spectroscopy,X-ray diffraction,scanning electron microscopy,BET specific surface area analysis and thermogravimetric analysis.In addition,the in-situ synthesis of papain@ZIF-8 using ZIF-8 as matrix was prepared and compared with papain@ZIF-F in morphology,structure,specific activity and stability.The characterization results showed that papain was embedded in ZIF skeleton,and the addition of enzyme did not affect the structural characteristics of ZIF skeleton,and the particle size of enzyme embedded in ZIF-F was up to 2μm.It is much higher than the 500 nm of ZIF-8,which may be because less 2-methylimidazole was added during the synthesis of ZIF-F,resulting in slower crystal growth and larger particle size.In terms of specific activity,papain@ZIF-F was significantly higher than that of free enzyme and papain@ZIF-8,up to 390 U/mg,200%higher than the specific activity of free enzyme.This may be because ZIF-F has a larger specific surface area and less resistance to the substrate,which is conducive to the full contact between the enzyme and the substrate,resulting in the increase of specific activity.Last,papain@ZIF-F was still higher than that of free enzyme after repeated use for five times,and the repeated use was good.

关 键 词：ZIF-F ZIF-8 木瓜蛋白酶 酶固定化 

分 类 号：TS201.2[轻工技术与工程—食品科学]