College of Food Science and Technology, Modern Biochemistry Experimental Center, Guangdong Ocean University, Guangdong Province Engineering Laboratory for Marine Biological Products, Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Zhanjiang 524088, PR China.
Institute of Agricultural Products Processing and Nuclear Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, PR China.
Enzyme Microb Technol. 2022 Jun;157:110017. doi: 10.1016/j.enzmictec.2022.110017. Epub 2022 Feb 11.
Enzyme immobilization technology has a key role in improving the stability of enzyme reaction systems and biocatalyst utilization rates. In this study, polyvinyl alcohol/sodium alginate@FeO (PVA/SA@FeO) magnetic immobilized-enzyme hydrogel beads were prepared. Their structure and morphology were characterized by scanning electron microscopy, surface area and porosity analyses, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and a vibrating sample magnetometer. The capability of PVA/SA@FeO to adsorb neutral protease was investigated with variations in composition, temperature, pH, stirring speed, enzyme concentration, and crosslinking concentration. The optimal parameters of the immobilization process were determined by response surface methodology (3% neutral protease, 4% crosslinking at 200 rpm, 45 °C and pH 7.2), under which an immobilization rate of 41.98 mg/g was obtained. The thermal stability, acid-base stability, and reusability of the immobilized enzyme were improved significantly. After seven cycles, the immobilized enzyme activity remained at 30.8% that of the initial enzyme activity. The results indicate that the immobilization of NP onto magnetic PVA/SA@FeO hydrogel beads improves enzyme efficiency, giving this process potential industrial applications.
酶固定化技术在提高酶反应体系的稳定性和生物催化剂利用率方面具有关键作用。本研究制备了聚乙烯醇/海藻酸钠@FeO（PVA/SA@FeO）磁性固定化酶水凝胶珠。通过扫描电子显微镜、比表面积和孔隙率分析、傅里叶变换红外光谱、X 射线光电子能谱和振动样品磁强计对其结构和形态进行了表征。通过改变组成、温度、pH 值、搅拌速度、酶浓度和交联浓度来研究 PVA/SA@FeO 吸附中性蛋白酶的能力。通过响应面法（3%中性蛋白酶，4%交联在 200rpm、45°C 和 pH7.2 下）确定了最佳的固定化工艺参数，在此条件下，固定化率为 41.98mg/g。固定化酶的热稳定性、酸碱稳定性和可重复使用性得到了显著提高。经过 7 次循环后，固定化酶的活性仍保持在初始酶活性的 30.8%。结果表明，NP 固定到磁性 PVA/SA@FeO 水凝胶珠上提高了酶的效率，使该工艺具有潜在的工业应用前景。
