title: Liquid and vapour-phase antifungal activities of essential oils against Candida albicans and non-albicans Candida.
abstract: BACKGROUND
  The management of Candida infections faces many problems, such as a limited number of antifungal drugs, toxicity, resistance of Candida to commonly antifungal drugs, relapse of Candida infections, and the high cost of antifungal drugs. Though azole antifungal agents and derivatives continue to dominate as drugs of choice against Candida infections, there are many available data referring to the anticandidal activity of essential oils. Since we have previous observed a good antimicrobial activity of some essential oils against filamentous fungi, the aim of this study was to extend the research to evaluate the activity of the same oils on Candida albicans, C.glabrata and C.tropicalis clinical strains, as well as the effects of related components. Essential oils selection was based both on ethnomedicinal use and on proved antibacterial and/or antifungal activity of some of these oils. Fluconazole and voriconazole were used as reference drugs.
  
  
  METHODS
  The minimum inhibitory concentration (MIC) and the minimal fungicidal concentration (MFC) of essential oils (thyme red, fennel, clove, pine, sage, lemon balm, and lavender) and their major components were investigated by the broth microdilution method (BM) and the vapour contact assay (VC).
  
  
  RESULTS
  Using BM, pine oil showed the best activity against all strains tested, though C.albicans was more susceptible than C.glabrata and C.tropicalis (MIC50-MIC90 = 0.06 %, v/v). On the contrary, sage oil displayed a weak activity (MIC50-MIC90 = 1 %, v/v). Thyme red oil (MIC50-MIC90 ≤ 0.0038 %, v/v for C.albicans and C.tropicalis, and 0.0078- < 0.015 %, v/v for C.glabrata), followed by lemon balm, lavender and sage were the most effective by VC. Carvacrol and thymol showed the highest activity, whereas linalyl acetate showed the lowest activity both by two methods. α-pinene displayed a better activity by BM than VC.
  
  
  CONCLUSIONS
  Results show a good activity of essential oils, mainly thymus red and pine oils, and their components carvacrol, thymol and α-pinene against Candida spp., including fluconazole/voriconazole resistant strains. These data encourage adequately controlled and randomized clinical investigations. The use in vapour phase could have additional advantages without requiring direct contact, resulting in easy of environmental application such as in hospital, and/or in school.
authors: Department of Public Health and Paediatrics, Microbiology Division, University of Turin, via Santena 9, 10126, Turin, Italy.
authors: Narcisa
authors: N
authors: Mandras
authors: Department of Pharmaceutical Sciences and Health Products Polo Annunziata, University of Messina, Viale S.S. Annunziata, 98168, Messina, Italy.
authors: Antonia
authors: A
authors: Nostro
authors: Department of Public Health and Paediatrics, Microbiology Division, University of Turin, via Santena 9, 10126, Turin, Italy.
authors: Janira
authors: J
authors: Roana
authors: Department of Public Health and Paediatrics, Microbiology Division, University of Turin, via Santena 9, 10126, Turin, Italy.
authors: Daniela
authors: D
authors: Scalas
authors: Department of Public Health and Paediatrics, Microbiology Division, University of Turin, via Santena 9, 10126, Turin, Italy.
authors: Giuliana
authors: G
authors: Banche
authors: Laboratory of Microbiology and Virology, Amedeo di Savoia Hospital, c.so Svizzera 164, 10149, Torino, Italy.
authors: Valeria
authors: V
authors: Ghisetti
authors: Laboratory of Microbiology and Virology, Amedeo di Savoia Hospital, c.so Svizzera 164, 10149, Torino, Italy.
authors: Simonetta
authors: S
authors: Del Re
authors: Chemical, Clinical and Microbiological Analyses Department, CTO, Turin, Italy.
authors: Giacomo
authors: G
authors: Fucale
authors: Department of Public Health and Paediatrics, Microbiology Division, University of Turin, via Santena 9, 10126, Turin, Italy.
authors: Anna Maria
authors: AM
authors: Cuffini
authors: Department of Public Health and Paediatrics, Microbiology Division, University of Turin, via Santena 9, 10126, Turin, Italy. vivian.tullio@unito.it.
authors: Vivian
authors: http://orcid.org/0000-0002-8660-4248
authors: V
authors: Tullio
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000494:pharmacology*; D002175:Candida / Q000187:drug effects*; D002176:Candida albicans / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D009822:Oils, Volatile / Q000737:chemistry / Q000494:pharmacology*; D010938:Plant Oils / Q000737:chemistry / Q000494:pharmacology*; D010946:Plants, Medicinal / Q000737:chemistry
chemical_list: D000935:Antifungal Agents; D009822:Oils, Volatile; D010938:Plant Oils
keywords: Antifungal activity; Broth microdilution method; Essential oils; Vapour contact assay; Yeasts