Influence of very low doses of mediators on fungal laccase activity - nonlinearity beyond imagination
Elzbieta Malarczyk, Janina Kochmanska-Rdest and Anna Jarosz-Wilkolazka
Laccase, an enzyme responsible for aerobic transformations of natural phenolics, in industrial
applications requires the presence of low-molecular substances known as mediators, which
accelerate oxidation processes. However, the use of mediators is limited by their toxicity and the
high costs of exploitation. The activation of extracellular laccase in growing fungal culture with
highly diluted mediators, ABTS and HBT is described. Two high laccase-producing fungal strains,
Trametes versicolor and Cerrena unicolor, were used in this study as a source of enzyme. Selected
dilutions of the mediators significantly increased the activity of extracellular laccase during 14 days
of cultivation what was distinctly visible in PAGE technique and in colorimetric tests. The same
mediator dilutions increased demethylation properties of laccase, which was demonstrated during
incubation of enzyme with veratric acid. It was established that the activation effect was assigned
to specific dilutions of mediators. Our dose-response dilution process smoothly passes into the
range of action of homeopathic dilutions and is of interest for homeopaths.