Methods for visualizing hyaline fungi for the detection of antifungal compounds on thin‐layer chromatograms

Abstract

Two methods facilitating the use of hyaline fungi for the detection of antifungal compounds on thin‐layer chromatograms are described. Fungal growth was visualized under ultraviolet light either by the metabolic release of fluorescein from the esterase substrate fluorescein diacetate, or by the binding of a fluorescent brightener (Calcofluor White M2R New, or Tinopal‐CBS) to the mycelium on the TLC plate.These methods were used to demonstrate compounds inhibitory to the wood‐decay fungus Heterobasidion annosum in bark extracts of Sitka spruce (Picea sitchensis).