(200f) Lignin Modification and Its Effect Upon Lignocellulose Degradation in Termite

Termites are highly effective in degrading lignocelluloses thus can be used as model for studying plant cell wall degradation in biological systems. The effectiveness of the termite system has been attributed to its highly efficient cellulases and its capability to grind particles into small sizes. The process of woody cell wall degradation in termite however, is still not well understood. One of the key questions is the role of lignin modification. At the same time when some of the current research suggested lignin processing in termite had insignificant effects on cellulose utilization, increasing evidences have become available that demonstrates lignin modification indeed occur in termite. Related research also showed the existence of genes of lignin degrading enzymes in the termite host, along with the chemical environment that favors lignin degradation. This paper presents the recent results obtained from our laboratory showing details in chemical bonding cleavage of lignin structure and speculated impact of the change of lignin structure upon subsequent hydrolysis of cellulose. The results provide useful information for understanding plant cell wall degradation and for developing new pretreatment processes for biochemical conversion of lignocellulosic biomass to fuels and chemicals.