Ksenija Radotic1 and Milorad Jeremic2

1Center for Multidisciplinary Studies, University of Belgrade, POB 373, 11000 Belgrade, Yugoslavia

2Faculty of Physical Chemistry, University of Belgrade, POB 137, 11000 Belgrade, Yugoslavia


Lignin is the second abundant polymer on the Earth, and it has constitutive and functional role in the plant cell walls. Free-radical polymerization of phenolic alcohols (coniferyl, p-coumaryl, synapyl alcohols), catalyzed by peroxidases, is adopted as the way of lignin synthesis in the cell walls.

Light has regulatory effect upon the developmental processes in the cells of all plant organs, even in roots. The cell wall is the first target place of light action in the cell. It has been recently found that short-wavelength UV light penetrates through the epidermal cell layer of the conifer needles into the mesophyl tissue1. It was shown before the ability of roots and seedlings to pipe light as light guides, almost without losses. Recently, many studies have shown the presence of the UV light receptor in the plant tissue1,2, moreover the receptor has not been yet identified.

In this work we studied the structure of a polymer synthesized by UV-irradiation of coniferyl alcohol and compared its structure with the structure of polymer obtained by peroxidase-catalyzed polymerization of coniferyl alcohol. This study may be primarily of ecological importance, since the UV radiation increases in particular regions of the Earth surface, due to the depletion of the ozone layer3.