INHIBITION OF FUNGAL GROWTH BY WATER EXTRACTS FROM THE LICHENNEPHROMA ARCTICUM

Water extracts fromNephroma arcticumwere prepared and tested for inhibitory effects against various yeast, mould, blue-stain and rot fungi. A water extract fromPeltigera aphthosawas used as a reference. Two different diffusion assays were used, wells (cup-plate method) and droplets (drop-plate method). For the majority of fungi studied using the former method there were clear zones with a sharp boundary (fungicidal effect), whereas the latter method yielded more or less hazy zones with inhibition or reduction in growth (fungistatic effect). No clear or hazy zones were seen with the extract fromP. aphthosa. ForCandida glabrataE,Saccharomyces cerevisiaeK andHormonema dematioidesS there were clear zones for both methods. The MIC (Minimum Inhibitory Concentration) values were determined in liquid medium forS. cerevisiaeK andC. glabrataE and were, respectively, 1 and 10mg ml−1of a crude extract fromN. arcticum. The MFC (Minimum Fungicidal Concentration) values were found to be identical to the MIC values.