Novel carboxyl-functionalized core-shell magnetic cellulose microspheres (MCMS) were prepared by surface modification with 1,2,3,4-butanetetracarboxylic acid (BTCA) and then applied in the immobilization of lysozyme via covalent bonding. The successful preparation of particles has been verified by transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and Fourier-transform infrared spectroscopy (FTIR) techniques. The optimal temperature and pH of the immobilized lysozyme were shown to be respectively 40 °C and 7. The immobilized lysozyme exhibited excellent performances within wide pH and temperature ranges as well as the high storage and thermal stabilities compared to free lysozyme. The apparent kinetic characterization of immobilized lysozyme revealed that its Km value was 1.37 times higher than that of free lysozyme and that its Vmax was slightly lower. The immobilized lysozyme demonstrated an acceptable reusability and showed 51.9±2.2% of activity after six cycles. This study demonstrated the application potential of BTCA-modified MCMS as an immobilized carrier for lysozyme.

中文翻译：

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将溶菌酶固定在 1,2,3,4-丁烷四羧酸 (BTCA) 修饰的磁性纤维素微球上以提高生物催化稳定性和活性

用1,2,3,4-丁烷四甲酸（BTCA）进行表面改性制备了新型羧基功能化核壳磁性纤维素微球（MCMS），并通过共价键用于溶菌酶的固定化。粒子的成功制备已通过透射电子显微镜 (TEM)、X 射线衍射 (XRD)、振动样品磁强计 (VSM) 和傅里叶变换红外光谱 (FTIR) 技术验证。固定化溶菌酶的最适温度和 pH 值分别为 40 °C 和 7。与游离溶菌酶相比，固定化溶菌酶在较宽的 pH 和温度范围内表现出优异的性能以及高储存和热稳定性。固定化溶菌酶的表观动力学特征表明其 Km 值为 1。比游离溶菌酶高37倍，Vmax略低。固定化溶菌酶表现出可接受的可重复使用性，并在六个循环后显示出 51.9±2.2% 的活性。该研究证明了 BTCA 修饰的 MCMS 作为溶菌酶固定化载体的应用潜力。