The oxidation of veratryl alcohol by the lignin peroxidase of Phanerochaete chrysosporium was studied. Five products were identified: veratraldehyde, two quinones and two aromatic ring cleavage lactones. A similar product pattern was obtained with the 1‐electron oxidant cerium(IV). Under anaerobic reaction conditions or in the presence of Mn(II) only traces of quinones or lactones were detected besides veratraldehyde. This indicates the involvement of activated oxygen species in the enzyme reaction. Possible mechanisms for the formation of the primary oxidation products from veratryl alcohol are discussed.

The oxidative degradation of 3,4-dimethoxybenzyl alcohol and 3,4-dimethoxybenzyl methyl ether by the lignin peroxidase (ligninase, LiP) of Phanerochaete chrysosporium was studied. In addition to previously isolated products of 3,4-dimethoxybenzyl alcohol oxidation (veratraldehyde, two quinones, ylactones, and a 5-lactone) three new products-4,5-dimethoxy-3,5-cyclohexadiene-l,2-dione, (£)-5-lactone, and 2,5-dihydroxy-4-methoxybenzaldehyde-were now identified as oxidation products. The relative quantities

Four major hemoproteins were purified by isoelectric focusing from an extracellular crude enzyme preparation, produced by the white rot fungus Phanerochaete chrysosporium under carbon‐limited conditions. Both the crude enzyme and the purified proteins oxidised milled wood lignin, HCl‐dioxane‐extracted straw lignin and alkali straw lignin in the presence of hydrogen peroxide. The oxidation resulted mainly in further polymerisation of the lignins and was enhanced by addition of veratryl alcohol to the reaction mixture. Alkali straw lignin was also polymerised by horseradish peroxidase, although veratryl alcohol had no influence on this reaction.

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