Lignin enzymatic modification

The location and the structure of lignin affects the enzymatic hydrolysis much more than the absolute quantities of lignin. The modification of the lignin surface by oxidative treatments with laccase and a delignification treatment results in an increased hydrolysis of the lignocellulose (34). 

Lund M, Ragauskas A (2001) Enzymatic modification of kraft lignin through oxidative coupling with watersoluble phenols. Appl Microbiol Biotechnol 55 699-703... 

Because polysaccharides have largely been degraded and so do not make a major contribution to coalified woods (Hatcher et al. 1989a), the chemical changes during lignite formation can be viewed in terms of modification of the lignin structure by microbial enzymatic attack. The sequence of reactions is quite well understood (Hatcher 1990), and is summarized in Fig. 4.7. 

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