水相中GOx@ZIF-7/PDA的制备及酶学性能研究  

Preparation of GOx@ZIF-7/PDA in aqueous phase and its enzymatic properties

作　　者：刘思媛 刘精杏 王则奋[2,3] 朱小璐 李妍雪 兰雄雕 刘彭如 蓝平 LIU Siyuan;LIU Jingxing;WANG Zefen;ZHU Xiaolu;LI Yanxue;LAN Xiongdiao;LIU Pengru;LAN Ping(School of Chemistry and Chemical Engineering,Guangxi Minzu University,Key Laboratory of Polysaccharide Materials and Modification,New Technology Laboratory of Chemical and Biological Transformation Process,Nanning 530006,China;School of Chemistry and Chemical Engineering,Guangxi University,Nanning 530000,China;Institute of Biological Manufacturing Technology Co.Ltd.,Guangxi Institute of Industrial Technology,Nanning 530000,China)

机构地区：[1]广西民族大学化学化工学院,广西多糖材料与改性重点实验室,广西高校化学与生物转化过程新技术实验室,广西南宁530006 [2]广西大学化学化工学院,广西南宁530000 [3]广西产研院生物制造技术研究所有限公司,广西南宁530000

出　　处：《食品与发酵工业》2023年第18期157-164,共8页Food and Fermentation Industries

基　　金：广西民族大学校引进人才科研启动项目(2018KJQD06);广西自然科学基金面上项目(2021GXNSFAA075043);广西自然科学基金青年基金项目(2022GXNSFBA035499);广西高校中青年教师基础能力提升项目(2019KY0170)。

摘　　要：原位包埋策略因制备条件温和、操作简单,被普遍应用在酶-金属有机骨架(metal-organic frameworks,MOFs)生物复合材料的制备中。但只有少部分MOFs能在水相中通过原位包埋法合成酶-MOFs生物复合材料。该研究首次在水相中采用原位包埋法将葡萄糖氧化酶(glucose oxidase,GOx)封装在ZIF-7(zeolitic imidazolate frameworks-7)载体中,并在所得的GOx@ZIF-7生物复合材料上合成了亲水性的聚多巴胺(polydopamine,PDA)修饰层,得到GOx@ZIF-7/PDA。采用单因素试验优化了GOx@ZIF-7/PDA的制备条件。结果表明,固定化pH值为7.0,酶质量浓度为5 g/L,苯并咪唑(benzimidazole,Bim)浓度为50 mmol/L,Zn^(2+)与苯并咪唑的摩尔比为1∶9,固定化温度为35℃,固定化时间为40 min,多巴胺的最佳质量浓度为2 g/L的条件下,GOx@ZIF-7/PDA具有最高酶活力回收率为(43.34±2.00)%。与游离酶相比,GOx@ZIF-7/PDA具有高的热稳定性、pH稳定性、贮存稳定性和良好的重复使用性,重复10次后,GOx@ZIF-7/PDA催化活性仍能保持(96.53±2.26)%。以上结果表明,水相原位包埋法制备固定化酶GOx@ZIF-7/PDA策略是高效可行的,有望实现低成本长期稳定的酶催化应用。Due to the mild preparation conditions and simple operation,in situ embedding strategy was widely used in the preparation of enzyme-metal organic frameworks(enzyme-MOFs)biocomposites.However,only part of MOFs was successfully employed to synthesize enzyme-MOFs through in situ embedding in aqueous phase.In this study,glucose oxidase(GOx)was encapsulated in zeolitic imidazolate framework-7(ZIF-7)via in situ embedding in aqueous phase for the first time.A hydrophilic polydopamine(PDA)layer was synthesized on the GOx@ZIF-7 to obtained GOx@ZIF-7/PDA.The preparation conditions of GOx@ZIF-7/PDA were optimized by single factor experiments.The optimized immobilization conditions for GOx@ZIF-7/PDA were showed as follows:immobilization pH 7.0,enzyme 5 g/L,Bim 50 mmol/L,molar ratio of Zn^(2+)to Bim 1∶9,immobilization temperature 35℃,immobilization time 40 min,dopamine 2 g/L.The enzyme activity recovery of GOx@ZIF-7/PDA reached up to(43.34±2.00)%under the optimal condition.Compared with free enzyme,GOx@ZIF-7/PDA achieved better thermal stability,pH stability,storage stability and excellent reuse performance.After 10 times of reuse,the catalytic activity of GOx@ZIF-7/PDA still maintained(96.53±2.26)%of its initial activity.These results indicated the strategy of preparing immobilized enzyme GOx@ZIF-7/PDA via in situ embedding in aqueous phase was efficient and feasible,and it was expected to achieve low cost and long-term stable application of enzyme catalysis.

关 键 词：葡萄糖氧化酶 金属有机骨架 酶固定化 ZIF-7 原位包埋法 多巴胺 

分 类 号：TB33[一般工业技术—材料科学与工程]