Alpha-guaiene isolated from patchouli oil exhibits antifungal activity against four pathogenic fungi

<ns3:p>Background The major component of patchouli oil, patchouli alcohol, is used as fixative and has antimicrobial activity. The function of other components, such as α-guaiene, remains unknown. Therefore, this study reports the antifungal activity of α-guaiene isolated from patchouli oil against for pathogenic fungi: <ns3:italic>Aspergillus niger</ns3:italic>, <ns3:italic>Candida albicans</ns3:italic> ATCC 7102, <ns3:italic>Microsporum gypseum</ns3:italic> ATCC 14683, and <ns3:italic>Trichophyton mentagrophytes</ns3:italic> ATCC 16404. Methods The material from fraction (249°C-254°C) had the highest α-guaiene. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) were determined using the microdilution technique to evaluate antifungal activity, with n-hexane and medium serving as negative controls, and ketoconazole and fluconazole serving as positive controls. Results The results showed that the MIC and MFC value were determined at 45%, 50% for <ns3:italic>C. albicans</ns3:italic>, 55%, 60% <ns3:italic>for A. niger</ns3:italic>, 50%, 60% for <ns3:italic>M. gypseum</ns3:italic>, and 95%, 100% for <ns3:italic>T. mentagrophytes</ns3:italic>, respectively. Positive and medium controls demonstrated no microbial growth, whereas negative and growth controls revealed the presence of microorganisms. Fungus resistance to α-guaiene <ns3:italic>T. mentagrophytes</ns3:italic> exhibited the highest MIC value. Conclusions Overall, this study reveals that α-guaiene is a promising agent effective against the studied pathogenic fungi.</ns3:p>