FTIR Analysis of the Lignin Structure Changes of APMP Treated by Laccase and Laccase/Mediator System

摘要

In this paper the two-stage method of enzyme-mild acidic hydrolysis was adopted to separate lignin from the APMP and the modified pulp samples. And then analyze the lignin structure changes of the modified APMP lignin by laccase and LMS(laccase/mediator system). It was found that no oxidation took place on carbohydrates in the LMS, and lignin Cα hydroxyl oxidization produce α carbonyl and H_2O_2 bleaching can also oxidation of lignin, make the conjugate C = α increase; the syringyl structure hydroxyl content increase, the lignin structure macromolecular side chain fracturing; Laccase and LMS oxidative degradation chromophoric group unsaturated C = O, which can improve the brightness of pulp and create better conditions for unbleached pulp.