State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China.
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China.
Bioresour Technol. 2014 Jul;164:248-53. doi: 10.1016/j.biortech.2014.04.105. Epub 2014 May 9.
To address the bottlenecks of laccase-based catalysis, i.e., poor long-term stability and potential secondary pollution caused by synthetic mediator, we fabricated a new biocatalyst (N-PS-Lac) through adsorption of laccase onto polystyrene anion exchangers (N-PS) binding quaternary ammonium groups. After 2-year storage, the residual activity of N-PS-Lac remained as high as 101.7%, while that for native laccase was only 14.6%. Also, N-PS-Lac exhibited improved durability against pH variation and thermal treatment at 60°C. Gaussian curve fitting of FT-IR spectra indicated that laccase conformation of N-PS-Lac was rigidified, possibly because of the host geometric restriction and the host-laccase electrostatic attraction. A two-step method, i.e., adsorption of an azo dye AO7 by N-PS and then ectopic degradation by the immobilized laccase, was proposed to reuse the mediator HOBT for seven cyclic runs, where N-PS-Lac kept the constant decolorization efficiency. AO7 solution was detoxified completely after decolorization by the two-step method.
为了解决漆酶催化的瓶颈问题，即合成介体导致的长期稳定性差和潜在的二次污染问题，我们通过将漆酶吸附到带有季铵基团的聚苯乙烯阴离子交换剂（N-PS）上来制备新型生物催化剂（N-PS-Lac）。经过 2 年的储存，N-PS-Lac 的剩余活性仍高达 101.7%，而天然漆酶的剩余活性仅为 14.6%。此外，N-PS-Lac 对 pH 值变化和 60°C 热处理的耐久性也有所提高。傅里叶变换红外光谱（FT-IR）的高斯曲线拟合表明，N-PS-Lac 中的漆酶构象变得更加刚性，这可能是由于主客体的几何限制和主客体之间的静电吸引力。我们提出了一种两步法，即 N-PS 吸附偶氮染料 AO7，然后通过固定化漆酶异位降解，使 HOBT 介体能够重复使用 7 个循环，在此过程中 N-PS-Lac 保持了恒定的脱色效率。两步法脱色后，AO7 溶液被完全解毒。
