In vitro activity of protoanemonin, an antifungal agent.

Protoanemonin, the lactone of gamma-hydroxy-vinylacrylic acid, isolated from Pulsatilla alpina has in vitro activity against fungi. The MIC is 15 micrograms/ml and RNA inhibition seems to be the first target of the drug. The LD50 of protoanemonin in male Swiss albino mice was 190 mg/kg.