The species Candida is a group of opportunistic pathogenic commensals in immune-compromised patients. Treatment of Candida infections is becoming increasingly difficult due to antifungal drug resistance, especially with fluconazole (FLC), which is a commonly used azole. In the present study the in vitro antifungal activity of eugenol (EUG) and methyleugenol (MEUG) alone and in combination against 64 FLC-sensitive and 34 FLC-resistant clinical Candida isolates is highlighted. All the strains were susceptible to both the naturally occurring phenyl propanoids. The nature of the interaction was studied from fractional inhibitory concentration indices (FICIs) for both EUG plus FLC, and MEUG plus FLC combinations calculated from chequerboard microdilution assays. FICI values depicted a high synergism of FLC with both compounds, which was greatest with MEUG. FLC-resistant Candida isolates showed high sensitivity to both compounds. No antagonistic activity was seen in the strains tested in the present study. From these results we suggest that EUG and MEUG have great potential as antifungals, and that FLC can be supplemented with EUG and MEUG to treat FLC-resistant Candida infections.
BragaP. C.,
SassoM. D.,
CuliciM.,
AlfieriM.2007; Eugenol and thymol, alone or in combination, induce morphological alterations in the envelope of Candida albicans
. Fitoterapia 78:396–400[CrossRef]
CantónE.,
PemánJ.,
GobernadoM.,
ViudesA.,
EspinelI. A.2005; Synergistic activities of fluconazole and voriconazole with terbinafine against four Candida species determined by checkerboard, time-kill, and Etest methods. Antimicrob Agents Chemother 49:1593–1596[CrossRef]
ChakrabartiA.,
ChatterjeeS. S.,
RaoK. L.,
ZameerM. M.,
ShivaprakashM. R.,
SinghiS.,
SinghR.,
VarmaS. C.2009; Recent experience with fungaemia: change in species distribution and azole resistance. Scand J Infect Dis 41:275–284[CrossRef]
HadizadehI.,
PeivasteganB.,
HamzehzarghaniH.2009; Antifungal activity of essential oils from some medicinal plants of Iran against Alternaria alternate
. Am J Appl Sci 6:857–861[CrossRef]
OnyewuC.,
BlankenshipJ. R.,
Del PoetaM.,
HeitmanJ.2003; Ergosterol biosynthesis inhibitors become fungicidal when combined with calcineurin inhibitors against Candida albicans , Candida glabrata , and Candida krusei
. Antimicrob Agents Chemother 47:956–964[CrossRef]
PintoE.,
Pina-VazC.,
SalgueiroL.,
GoncalvesM. J.,
Costa-de-OliveiraS.,
CavaleiroC.,
PalmeiraA.,
RodriguesA.,
Martinez-de-OliveiraJ.2006; Antifungal activity of the essential oil of Thymus pulegioides on Candida , Aspergillus and dermatophyte species. J Med Microbiol 55:1367–1373[CrossRef]
PintoE.,
Vale-SilvaL.,
CavaleiroC.,
SalgueiroL.2009; Antifungal activity of clove essential oil from Syzygium aromaticum on Candida , Aspergillus and dermatophyte species. J Med Microbiol 58:1454–1462[CrossRef]
RosatoA.,
VialiC.,
GalloD.,
MillilloM. A.,
MallamaciR.2008; The inhibition of Candida species by selected oils and their synergism with amphotericin B. Phytomedicine 15:635–638[CrossRef]
RosatoA.,
VitaliC.,
PiarulliM.,
MazzottaM.,
ArgentieriM. P.,
MallamaciR.2009; In vitro synergic efficacy of the combination of Nystatin with the essential oils of Origanum vulgare and Pelargonium graveolens against some Candida species. Phytomedicine 16:972–975[CrossRef]
SanglardD.,
IscherF.,
ParkinsonT.,
FalconerD.,
BilleJ.2003; Candida albicans mutations in the ergosterol biosynthetic pathway and resistance to several antifungal agents. Antimicrob Agents Chemother 47:2404–2412[CrossRef]
TariqV. N.,
ScottE. M.,
McCainN. E.1995; Use of decimal assay for additivity to demonstrate synergy in pair combinations of econazole, nikkomycin Z, and ibuprofen against C. albicans in vitro
. Antimicrob Agents Chemother 39:2615–2619[CrossRef]