THE MYSTERY OF THE LIGNIN-CARBOHYDRATE COMPLEX - A COMPUTATIONAL APPROACH

Molecular mechanics calculations were performed on model linear chains of lignin and carbohydrate polymeric structures of living plants and soil humic materials. Among possible lignin chain conformers that resu lt from minimum-energy conformers of dimeric units, a broad regular he lix may contain a carbohydrate ribbon inside itself. This structure pr ovides an energy gain in comparison with other ways of mutual adjustme nt of lignin and carbohydrate polymers. Oxidation of lignin into respe ctive humic acids sharply changes the spatial organization of the init ial polymer only if it is not associated with a carbohydrate.