Essential oil compounds fromAgastache rugosa as antifungal agents againstTrichophyton species


The antifungal activities of the essential oil fromAgastache rugosa and its main component, estragole, combined with ketoconazole, one of the azole antibiotics commonly used to treat infections caused byTrichophyton species, were evaluated in this study. The combined effects were measured by the checkerboard microtiter and the disk diffusion tests, againstT. erinacei, T. mentagrophytes, T. rubrum, T. schoenleinii andT. soudanense. Susceptibility of the fiveTrichophyton species to the oil alone, or ketoconazole alone, differed distinctly. The fractional inhibitory concentration indices (FICI) of ketoconazole combined with estragole orA. rugosa essential oil, against the testedTrichophyton species, were between 0.05 and 0.27, indicating synergistic effects. These drug combinations exhibited the most significant synergism againstT. mentagrophytes, with FICIs of 0.05 and 0.09 for estragole and the essential oil fraction fromA. rugosa, respectively. Isobolograms based on the data from checkerboard titer tests also indicated significant synergism between ketoconazole and theAgastache oil fraction or estragole, against theTrichophyton species evaluated.Trichophyton susceptibility to ketoconazole was significantly improved by combination with theAgastache rugosa oil fraction or its main component, estragole.

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Correspondence to Seungwon Shin.

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Shin, S. Essential oil compounds fromAgastache rugosa as antifungal agents againstTrichophyton species. Arch Pharm Res 27, 295–299 (2004).

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Key words

  • Trichophyton
  • Agastache rugosa
  • Essential oil
  • Estragole
  • Ketoconazole
  • Synergism