Co-innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, 210037, China.
Department of Food Science and Technology, College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, 210037, China.
Appl Biochem Biotechnol. 2021 Feb;193(2):446-462. doi: 10.1007/s12010-020-03446-z. Epub 2020 Oct 6.
Immobilization of enzyme based on combination of adsorption and cellulose derivative membrane coating was established in this work for the first time. Laccase, a commonly used enzyme in varied fields, was chosen as the model enzyme to demonstrate this method. After investigating operational conditions, the optimal process was obtained as follows: diatomite or HPD-417 as the adsorption carrier, 0.5% (w/v) methylcellulose (40,000~50,000) acetone solution as the coating solution, 0.75% (w/v) polyethylene glycol or maltose as the protective agent, and drying at 4 °C for 9 h. Under the optimal conditions, the residual activities of diatomite and HPD-417 immobilized laccase reached 99.33% and 94.15%, respectively. The study on properties showed that the immobilized laccases held high pH tolerance and thermal stability. The immobilized laccases were further applied to the indigo decolorization and 2, 4-dichlorophenol degradation. They showed high catalytic efficiency and could be reused for several batches. On the whole, the immobilization method developed in this work can effectively avoid the inactivation of laccase during immobilization and improve the stability of immobilized laccase. The laccase immobilized by this method shows obvious potential for environmental governance.
本文首次建立了基于吸附和纤维素衍生物膜涂层结合的酶固定化方法。选择漆酶作为模型酶来验证这种方法，漆酶是一种在不同领域广泛应用的常用酶。在考察操作条件后，得到了最佳的工艺条件如下：硅藻土或 HPD-417 作为吸附载体，0.5%（w/v）甲基纤维素（40,000~50,000）丙酮溶液作为涂层溶液，0.75%（w/v）聚乙二醇或麦芽糖作为保护剂，在 4°C 下干燥 9 h。在最佳条件下，硅藻土和 HPD-417 固定化漆酶的残余酶活分别达到 99.33%和 94.15%。对性质的研究表明，固定化漆酶具有较高的 pH 耐受性和热稳定性。固定化漆酶进一步应用于靛蓝脱色和 2,4-二氯苯酚降解，表现出较高的催化效率，可重复使用多批次。总的来说，本研究开发的固定化方法可以有效地避免漆酶在固定化过程中的失活，提高固定化漆酶的稳定性。该方法固定化的漆酶在环境治理方面具有明显的应用潜力。
