Abstract: A composition comprises an azo dye having a lignin-like substitution pattern and an environmentally common microbe, such as Streptomyces or Phanerochaete chrysosporium. The composition may also comprise an azo dye having a lignin-like substitution pattern, an amount of lignin peroxidase effective to degrade the dye, and an amount of veratryl alcohol effective to recycle lignin peroxidase II to lignin peroxidase. The lignin peroxidase may be provided by an environmentally common microbe. Azo dyes substituted with lignin-like groups are completely mineralized by the environmentally common microbe. The biodegradable azo dye preferably includes a first aromatic ring having a first substituent R1 selected from hydroxy or lower alkoxy, a second substituent R2 selected from lower alkyl or lower alkoxy, and a third substituent R3 selected from lower alkoxy or halogen. In especially preferred embodiments the first substituent R.sub.1 is hydroxy and is para to the azo group, and both R.sub.2 and R.sub.

Abstract: A biodegradable azo dye contains a nitrogen atom linked to an aromatic ring having a lignin-like substitution pattern. The ring is preferably a syringyl or guaiacol moiety, and provides a naturally-occurring structure for attack by microorganisms, such as Streptomyces or Phanerochaete. In especially preferred embodiments, the aromatic ring has a first substituent R.sub.1 selected from among hydroxy, lower alkoxy, or amino, and a second substituent R.sub.2 selected from among lower alkyl, lower alkoxy and halogen. Some embodiments include a third ring substituent R.sub.3 selected from the group lower alkyl, lower alkoxy, and halogen.