Identification of signature volatiles to discriminate Candida albicans, glabrata, krusei and tropicalis using gas chromatography and mass spectrometry

Mycoses. 2016 Feb;59(2):117-26. doi: 10.1111/myc.12442. Epub 2015 Dec 14.

Abstract

Oral candidiasis is the most frequent fungal infection of the oral cavity. Clinical diagnoses require mycological confirmation, which is time-consuming in case of culture testing. The aim of the study was to identify signature volatiles to develop a chairside breath test to diagnose oral candidiasis. Headspaces above Candida albicans, glabrata, tropicalis, krusei cultures, and growth media as control were analysed after eight and 24 h using offline gas chromatography and mass spectrometry. The identification of signature volatiles was assisted using various microbial databases. Retrieved volatile patterns enabled Candida species discrimination in vitro. For C. albicans 3-methyl-2-butanone and styrene and for C. krusei a combination of p-xylene, 2-octanone, 2-heptanone and n-butyl acetate were found to be specific. 1-hexanol was found in C. tropicalis, but is emitted by a variety of other microorganisms. C. glabrata was characterised through the absence of these volatiles. The development of a breath test is a promising approach in confirming suspicions of oral candidiasis. To confirm the retrieved results in vivo, breath tests in affected and healthy subjects have to be performed.

Keywords: Candida spp.; breath test; oral candidiasis; volatile organic compounds.

MeSH terms

  • Acetates / analysis
  • Adult
  • Breath Tests
  • Candida / chemistry
  • Candida / classification*
  • Candida / isolation & purification*
  • Candida albicans / classification
  • Candida albicans / isolation & purification
  • Candida glabrata / classification
  • Candida glabrata / isolation & purification
  • Candida tropicalis / classification
  • Candida tropicalis / isolation & purification
  • Candidiasis, Oral / diagnosis*
  • Candidiasis, Oral / microbiology
  • Chromatography, Gas / methods
  • Diagnosis, Differential
  • Hexanols / analysis
  • Humans
  • Ketones / analysis
  • Male
  • Mass Spectrometry / methods
  • Pentanones / analysis
  • Styrene / analysis
  • Volatile Organic Compounds / analysis*
  • Xylenes / analysis

Substances

  • Acetates
  • Hexanols
  • Ketones
  • Pentanones
  • Volatile Organic Compounds
  • Xylenes
  • Styrene
  • butyl acetate
  • 1-hexanol
  • 4-xylene
  • 2-heptanone
  • 2-octanone
  • isopropyl methyl ketone