EFFECT OF CHLOROMETHANE ON VERATRYL ALCOHOL AND LIGNIN PEROXIDASE PRODUCTION BY THE FUNGUS PHANEROCHAETE-CHRYSOSPORIUM

Biosynthesis of veratryl alcohol, a secondary metabolite considered to be an important component of the lignin-degrading system in the fungus Phanerochaete chrysosporium Burds INA-12, was initiated up to 36 h earlier in fungal cultures supplemented with 0.6 and 1.25 mM-CH3Cl compared with unsupplemented mycelia. Peak concentrations of the idiolyte were also about 70% higher in the presence of 0.6 mM-CH3Cl, although peak levels elicited by 0.2, 0.4 and 1.25 mM-CH3Cl were lower than in unsupplemented cultures. Advanced initiation of veratryl alcohol biosynthesis in the presence of CH3Cl was reflected in the earlier appearance of lignin peroxidase (LiP) activity. This effect was most noticeable in cultures supplemented with 0.4 and 0.6 mM-CH3Cl, where LiP was evident up to 24 h before detection in unsupplemented cultures. However, peak levels of LiP produced by CH3Cl-augmented mycelia were always less - below 40% in the case of 1.25 mM-CH3Cl - than those recorded in cultures without supplementation. These effects may be explained by restricted metabolic availability of CH3Cl as methyl donor for veratryl alcohol biosynthesis in the early stages of fungal growth.