Two Types of Growth Inhibitors in Extracts of Umbilicaria papulosa

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Abstract
Samples of the lichen Umbilicaria papulosa (Ach. ) Nyl. were extracted with 80% ethanol. The extracts were evaporated to dryness, taken up in water, and tested for phytocidal and fungicidal activity. Activated charcoal (Norit A) adsorbed all biologically active principles from the extract. The phytocidal component was eluted with acetone, water, and ammonia (60: 39: 1). The antifungal component could not be eluted by the above mixture, by ethanol, ether, or pyridine. Both antifungal and phytocidal substances diffused through a cellophane membrane. Fractionation of the crude lichen extract indicated that the antifungal agent was ethersoluble, whereas the phytocide remained in the aqueous phase. Brown needle-shaped crystals prepared from the lichen extracts were identified as ethyl orsellate The crystals showed strong antifungal activity but only slight potency as a phytocide. Orcinol has been identified in the ether phase of the extract.