(73b) Understanding the Impact of Lignin On Enzymatic Saccharification of Lignocellulosic Substrate

Lignin is a major obstacle to enzymatic saccharification of lignocellulose. However, the mechanism of the lignin-enzyme interaction is not completely clear. This study is to investigate how lignin impacts cellulases and to fundamentally understand the relationship between lignin structure and the impact. Lignin retards the enzymatic saccharification of lignocellulose by acting as a physical barrier (restricting the access of cellulases to cellulose) and by irreversibly adsorbing cellulases (resulting in non-productive binding of the enzymes). Irreversible adsorption of enzymes on lignin also limits the enzyme recycle and reuse. It is apparent that lignin content and distribution have substantial impact on enzymatic hydrolysis of cellulose. However, the inhibitory effect of lignin is not only depending on its content but also its chemical experience and structural features, such as hydrophilicity and functional groups.