A lignin-degrading enzyme has been detected in culture supernatants of Phanerochaete chrysosporium strain INA-12 grown under non-limiting nitrogen conditions. Highest levels of enzyme activity were observed when glycerol served as carbon source. Veratryl alcohol, a known secondary metabolite of P. chrysosporium, was also produced in high nitrogen/glycerol cultures of strain INA-12 and closely followed the development of the ‘ligninase’ activity. Evolution of 14CO2 from 14C-ring-DHP was readily observed when a hydrogen peroxide-generating system was added to 5-day-old high nitrogen/glycerol cultures which contained high amounts of enzyme.