Department of Chemical Science and Engineering, National Institute of Technology, Ariake College, 150 Higashihagio-Machi, Omuta, Fukuoka 836-8585, Japan.
Department of Chemical Science and Engineering, National Institute of Technology, Ariake College, 150 Higashihagio-Machi, Omuta, Fukuoka 836-8585, Japan.
Int J Biol Macromol. 2019 Jun 1;130:737-744. doi: 10.1016/j.ijbiomac.2019.03.004. Epub 2019 Mar 2.
Radiation-induced graft polymerization was applied to prepare membranes for multilayer immobilization of laccase, which has biodegradation ability for bisphenol A (BPA). Glycidyl methacrylate (GMA) was grafted onto porous polyethylene membranes as the monomer of polymer brushes, and aminoethanol (AE) was introduced to the grafted GMA membrane, creating unfolded polymer brushes that serve as a good support for multilayer immobilization of laccase. The objectives of this study were as follows: adjustment of space velocity (SV) for optimum performance; enhancement of stability in organic media through moisture retention; biodegradation of BPA at continuous operation; and investigation of the effects of redox mediators. Laccase and membrane activities were increased at higher SVs as a result of stronger substrate transport. The 1.85% moisture retention as a result of high-density AE containing polymer brushes demonstrated the improved stability of immobilized laccase over free laccase in methanol-containing solutions. BPA was removed with an activity of 0.11 mol/h/kg-membrane. The effects of three major laccase mediators on BPA oxidation was studied, and only 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) was shown to increase the oxidation of BPA to 100% at low SVs. Improved stability of laccase and high removal rates in the continuous biodegradation of BPA were achieved by the presented method.
辐射接枝聚合被应用于制备多层固定化漆酶的膜，漆酶具有双酚 A（BPA）的生物降解能力。甲基丙烯酸缩水甘油酯（GMA）被接枝到多孔聚乙烯膜上作为聚合物刷的单体，并且引入了氨基乙醇（AE）到接枝的 GMA 膜中，形成展开的聚合物刷，作为多层固定化漆酶的良好支撑。本研究的目的如下：调整空间速度（SV）以达到最佳性能；通过保持水分来提高在有机介质中的稳定性；在连续操作中生物降解 BPA；以及研究氧化还原介质的影响。由于较强的底物传输，漆酶和膜活性在较高的 SV 下增加。由于含有高密度 AE 的聚合物刷保留了 1.85%的水分，固定化漆酶在甲醇溶液中的稳定性比游离漆酶得到了提高。BPA 的去除率为 0.11 mol/h/kg-膜。研究了三种主要漆酶介质对 BPA 氧化的影响，只有 2,2'-联氮双（3-乙基苯并噻唑啉-6-磺酸）在低 SV 下显示出增加 BPA 氧化到 100%的效果。通过所提出的方法，实现了漆酶的稳定性提高和 BPA 连续生物降解的高去除率。
