Aryl alcohol oxidase (AAO) produced by Geotrichum candidum Dec1(Dec1), a ne
wly isolated decolorizing fungus, was purified by ultrafiltration and by us
ing diethylaminoethyl (DEAE) Sephacel, Butyl-Toyopearl and Mono-Q columns.
H2O2 produced by concomitant AAO oxidation of veratryl alcohol (VA) to vera
traldehyde was consumed by a peroxidase (DyP) purified from Dec1 culture, l
eading to the decolorization of a dye in vitro. In the liquid culture of De
c1, the existence of H2O2 and veratraldehyde was confirmed during cultivati
on, when dye-decolorization and AAO activities were maintained. This indica
tes that VA produced by Dec1 was oxidized by AAO to veratraldehyde, generat
ing H2O2, which supported dye-decolorizing activity of Dec1 in vivo. The pr
evention of polymerization of DyP oxidation products of a dye in the presen
ce of AAO was shown.