The influence of tea tree oil (Melaleuca alternifolia) on fluconazole activity against fluconazole-resistant Candida albicans strains.
The aim of this study was to evaluate the activity of fluconazole against 32 clinical strains of fluconazole-resistant Candida albicans, and C. albicans ATCC 10231 reference strain, after their exposure to sublethal concentrations of tea tree oil (TTO) or its main bioactive component terpinen-4-ol. For all tested fluconazole-resistant C. albicans strains TTO and terpinen-4-ol minimal inhibitory concentrations (MICs) were low, ranging from 0.06% to 0.5%. The 24-hour exposure of fluconazole-resistant C. albicans strains to fluconazole with sublethal dose of TTO enhanced fluconazole activity against these strains. Overall, 62.5% of isolates were classified as susceptible, 25.0% exhibited intermediate susceptibility, and 12.5% were resistant. For all of the tested clinical strains the fluconazole MIC decreased from an average of 244.0 μg/mL to an average of 38.46 μg/mL, and the fluconazole minimal fungicidal concentrations (MFC) decreased from an average of 254.67 μg/mL to an average of 66.62 μg/mL. Terpinen-4-ol was found to be more active than TTO, and strongly enhanced fluconazole activity against fluconazole-resistant C. albicans strains. The results of this study demonstrate that combining natural substances such as TTO and conventional drug such as fluconazole, may help treat difficult yeast infections.
Department of Microbiology and Immunology, Medical University of Silesia in Katowice, Jordana 19, 41-808 Zabrze, Poland.
Anna
0000-0003-0796-8818
A
Mertas
Department of Microbiology and Immunology, Medical University of Silesia in Katowice, Jordana 19, 41-808 Zabrze, Poland.
Aleksandra
A
Garbusińska
Department of Microbiology and Immunology, Medical University of Silesia in Katowice, Jordana 19, 41-808 Zabrze, Poland.
Ewelina
0000-0001-8114-2112
E
Szliszka
Department of Microbiology and Immunology, Medical University of Silesia in Katowice, Jordana 19, 41-808 Zabrze, Poland.
Andrzej
0000-0002-7052-6548
A
Jureczko
Department of Microbiology and Immunology, Medical University of Silesia in Katowice, Jordana 19, 41-808 Zabrze, Poland.
Magdalena
M
Kowalska
Department of Microbiology and Immunology, Medical University of Silesia in Katowice, Jordana 19, 41-808 Zabrze, Poland.
Wojciech
W
Król
D000935:Antifungal Agents / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects*; D002177:Candidiasis / Q000188:drug therapy* / Q000382:microbiology; D025141:Drug Resistance, Fungal / Q000187:drug effects*; D015725:Fluconazole / Q000494:pharmacology; D006801:Humans; D020947:Tea Tree Oil / Q000494:pharmacology*
D000935:Antifungal Agents; D020947:Tea Tree Oil; D015725:Fluconazole