ABSTRACT
The UV–Vis. absorption of ferulic acid and related compounds may be considerably augmented by substitution and environment. Among the circumstances investigated in the present study, esterification (mostly to polysaccharides in plant cell wall), dehydrodimerization and inclusion in a cellulose matrix substantially cause the absorption to increase and extend into the visible region. As a result of the combination of these three effects, dehydrodiferulate type units appear to be the most likely chromophore among the ferulic acid-derived structures.