Lignin demethoxylation was studied using enzyme extracts from Gloeophilum trabeum. The synthesis of enzyme complexes in semisolid cultures is described together with the incorporation of Fe-55 to identify metalproteins. The demethoxylation activity of enzyme extracts were tested with lignin-model compounds : veratric alcohol; veratric aldehyde; anisoin. Demethoxylated products were identified by thin layer chromatography and reverse phase high-pressure liquid chromatography. Methanol was identified as a reaction product when vanillin and syringic acid were used as substrates. Demethoxylation of lignin by fungi can be an important step for the production of biodegradable polymers such as polyurethanes, as a result of the transformation of methoxylated substrates into hydroxylated products.