Wang Wei, Liu Jiayuan, Khan Muhammad Junaid, Wang Rong, Francesco Secundo, Sun Jianan, Mao Xiangzhao, Huang Wen-Can
State Key Laboratory of Marine Food Processing and Safety Control, College of Food Science and Engineering, Ocean University of China, Qingdao 266404, China; Qingdao Key Laboratory of Food Biotechnology, Qingdao 266404, China; Key Laboratory of Biological Processing of Aquatic Products, China National Light Industry, Qingdao 266404, China.
State Key Laboratory of Marine Food Processing and Safety Control, College of Food Science and Engineering, Ocean University of China, Qingdao 266404, China.
Int J Biol Macromol. 2024 Jan;256(Pt 2):128214. doi: 10.1016/j.ijbiomac.2023.128214. Epub 2023 Nov 21.
In this study, a novel magnetic macroporous chitin microsphere (MMCM) was developed for enzyme immobilization. Chitin nanofibers were prepared and subsequently subjected to self-assembly with magnetic nanoparticles and PMMA (polymethyl methacrylate). Following this, microspheres were formed through spray drying, achieving a porous structure through etching. The MMCM serves as an effective support for immobilizing enzymes, allowing for their covalent immobilization both on the microsphere's surface and within its pores. The substantial surface area resulting from the porous structure leads to a 2.1-fold increase in enzyme loading capacity compared to non-porous microspheres. The MMCM enhances stability of the immobilized enzymes under various pH and temperature conditions. Furthermore, after 20 days of storage at 4 °C, the residual activity of the immobilized enzyme was 2.93 times that of the free enzyme. Even after being recycled 10 times, the immobilized enzyme retained 56.7 % of its initial activity. It's noteworthy that the active sites of the enzymes remained unchanged after immobilization using the MMCM, and kinetic analysis revealed that the affinity of the immobilized enzymes rivals that of the free enzymes.
在本研究中，开发了一种新型磁性大孔几丁质微球（MMCM）用于酶固定化。制备了几丁质纳米纤维，随后使其与磁性纳米颗粒和聚甲基丙烯酸甲酯（PMMA）进行自组装。在此之后，通过喷雾干燥形成微球，并通过蚀刻实现多孔结构。MMCM作为固定化酶的有效载体，允许酶在微球表面及其孔内进行共价固定。多孔结构产生的大量表面积导致酶负载能力比无孔微球提高了2.1倍。MMCM在各种pH和温度条件下增强了固定化酶的稳定性。此外，在4℃储存20天后，固定化酶的残余活性是游离酶的2.93倍。即使循环使用10次后，固定化酶仍保留其初始活性的56.7%。值得注意的是，使用MMCM固定化后酶的活性位点保持不变，动力学分析表明固定化酶的亲和力与游离酶相当。
