Effect of aromatic compounds on growth and ligninolytic enzyme production of two white rot fungi Ceriporiopsis subvermispora and Cyathus stercoreus

Seven benzoic acid, ten cinnamic acid,and five benzaldehyde derivatives wer e tested for their effects on hyphal growth and production of laccase and m anganese peroxidase by Ceriporiopsis subvermispora FP 90031-sp and Cyathus stercoreus ATCC 36910. Derivatives tested included phenolic compounds and t heir corresponding unsubstituted and O-methylated derivatives. Benzaldehyde derivatives were more toxic to both fungi than the corresponding benzoic a nd cinnamic acid derivatives. Hyphal growth was generally increased at a lo w concentration of 1 mM, while higher concentrations of 5-10 mM mostly resu lted in less or no growth. Hyphal growth and enzyme production response wer e compound specific. However, generally monomethoxylated compounds were mor e toxic than compounds with an additional methoxyl group. Cyathus stercoreu s was more sensitive than Ceriporiopsis subvermispora to most of the compou nds tested and thus showed poorer growth. Cyathus stercoreus produced highe r concentrations of manganese peroxidase than Ceriporiopsis subvermispora f or all the compounds tested, whereas laccase activity was higher in Ceripor iopsis subvermispora for most of the compounds tested. Di- and tri-methoxyl ated compounds induced more laccase and manganese peroxidase activities tha n the corresponding hydroxylated derivatives. At 1 mM levels, 3,4-dimethoxy cinnamic acid induced the greatest increase in laccase production for Cerip oriopsis subvermispora and Cyathus stercoreus (245 and 290% of control, res pectively). Syringic acid induced manganese peroxidase (MnP) to 536% of tha t in control for Ceriporiopsis subvermispora, and both 3,4-dimethoxycinnami c acid and 3,4,5-trimethoxycinnamic acid induced MnP to over 300% of contro l for Cyathus stercoreus. The results provide a body of information on the effects of specific aromatic compounds on two potentially industrially impo rtant fungi.