Substrate-induced H2O2 production in mycelia from the lignin-degrading fungus Phanerochaete chrysosporium

Abstract

Broken and subsequently washed mycelia from the lignin-degrading fungus Phanerochaete chrysosporium generated increased levels of H2O2 when exposed to a lignocellulosic substrate (ground wheat straw) or substrate analogue (Poly B-411). H2O2 production was observed only in cultures grown on limiting nitrogen, a condition known to induce the lignin-degrading activity of this organism. H2O2 production was observed in the pH range of 4.5 to 8.4, but the highest levels of H2O2 were generated around pH 6. The mycelia also exhibited catalase activity, which was 5- to 10-fold higher in nitrogen-limited cultures.