Department of Chemical Engineering, University of Vigo, Lagoas Marcosende s/n, E-36310 Vigo, Spain.
Bioresour Technol. 2013 Mar;131:288-94. doi: 10.1016/j.biortech.2012.12.155. Epub 2013 Jan 3.
The capacity of laccase from Myceliophthora thermophila to promote the oxidative polymerisation of Kraft lignin (KL) was evaluated in several conditions of pH, temperature, enzyme dosage and treatment time. Moreover, different black liquors from the Kraft cooking of Eucalyptus globulus and mixture of Pinus pinaster/E. globulus were evaluated in order to determine the effect of the KL source on the polymerisation reaction. Furthermore, one of these black liquors was fractionated by sequential organic solvent fractionation and the polymerisation of the corresponding fractions was tested. Polymerisation products were analysed by size exclusion chromatography and Fourier transform infrared spectroscopy. The results provide evidence of notable lignin modifications after incubation with laccase. Structural oxidation and a notably molecular weight increase were attained, reaching a polymer of 69-fold its initial molecular weight depending on the raw lignin. Moreover, optimum values of reaction conditions were obtained: pH 7.3, 70°C, 2UmL(-1) and 2h.
评估了嗜热毁丝霉漆酶促进 kraft 木质素（KL）氧化聚合的能力，考察了 pH 值、温度、酶剂量和处理时间等条件。此外，还评估了不同的桉木 kraft 蒸煮黑液和欧洲赤松/桉树混合物黑液，以确定 KL 来源对聚合反应的影响。进一步地，其中一种黑液通过顺序有机溶剂分级，测试了相应级分的聚合。通过尺寸排阻色谱和傅里叶变换红外光谱分析聚合产物。结果表明，漆酶孵育后木质素发生了显著的修饰。实现了结构氧化和分子量显著增加，聚合产物的分子量达到初始分子量的 69 倍，这取决于原始木质素。此外，还获得了最佳的反应条件：pH 值 7.3、70°C、2UmL(-1)和 2h。
