Chemical Engineering Department, ETSEIAT, Universitat Politècnica de Catalunya, Colom 11, E-08222 Terrassa, Spain.
Bioresour Technol. 2013 Feb;130:431-8. doi: 10.1016/j.biortech.2012.12.014. Epub 2012 Dec 14.
This paper evaluates five phenolic compounds as mediators for kenaf pulp biobleaching by laccase. The results have been compared with the treatment using a non-phenolic mediator, 1-hydroxybenzotriole and laccase alone. The influence of the nature of the chemical mediators used on various pulp properties is discussed. In addition to oxidizing lignin, the phenolic radicals formed in the process take part in condensation and grafting reactions in enzymatic stage. After biobleaching sequence (LP), syringaldehyde was shown to be the best phenolic mediator, allowing a delignification of 43% and 72% ISO brightness. These results were similar to the use of laccase alone due to the role as mediators of syringyl units resulting from oxidative lignin degradation. As a novelty, the study was supplemented with thermogravimetric analysis, with emphasis on the crystallinity degree of the cellulose surface and the aim of elucidating the action mechanisms of laccase-mediator systems on fiber.
本文评价了 5 种酚类化合物作为介体在辣根过氧化物酶作用下对剑麻浆生物漂白的效果。将其与使用非酚类介体 1-羟基苯并三唑和单独使用辣根过氧化物酶的处理进行了比较。讨论了使用不同化学介体对各种纸浆性能的影响。除了氧化木质素外，在酶促阶段，形成的酚类自由基还参与缩合和接枝反应。生物漂白序列（LP）后，间苯二甲醛被证明是最好的酚类介体，可实现 43%和 72%ISO 白度的脱木质素。由于氧化木质素降解生成的愈创木基单元具有介体作用，这些结果与单独使用辣根过氧化物酶相似。作为一项创新，该研究还补充了热重分析，重点是纤维素表面的结晶度，并旨在阐明漆酶-介体系统对纤维的作用机制。
