The Impact of Essential Oils on Candida albicans: An Evaluation of Antifungal Activity

Abstract

Candida albican is the largest human fungal pathogen worldwide. Oral candidiasis; oral thrush may be a moderate to serious oral infection triggered by Candida species overgrowth and numerous essential oils have been already reported to have antifungal qualities and may be useful as agents that fight mycosis. We have assessed the in-vitro inhibitory activity of certain essential oils and the combination of the most efficient essential oil against strain of Candida albican. According to literature EOs shows great antifungal properties in in-vitro experiments. In in-vitro trials, geranium and citronella essential oils have demonstrated impressive antifungal efficacy and support a variety of therapeutic applications for general medical conditions in the treatment or control of a wide range of diseases. Six commercial essential oils were tested by using a disc diffusion method on SDA media. Gas chromatography/mass spectroscopy analyses of the oils tested were performed. The essential oils of Citronella (Cymbopogon nardus) shows maximum ZOI (64±0.816) and geranium (Pelargonium graveolens) has moderate activity (25.33±0.62) whereas eucalyptus (Eucalyptus citriodora) (20±0.62) , lemongrass (Cymbopogon citratus) (21.67±0.86 ), patchouli (Pogostemon cablin )(18±1.63 )and orange oil (Citrus sinensis)  (18.67±0.40)  shows minimum ZOI. MIC values of both geranium and citronella oils against C.albicans were 6.25×10³ μg/mL and 3.125×10³ μg/mL, respectively. To determine the combined efficiency of essential oils checkerboard method was adopted. Three different ratios of citronella and geranium Eos were used ie; (1:0.25), (1:0.5) and (1:1) synergistic study for citronella and geranium oils ie;concentration ratio of (1:0.25) shows FICI 0.75 which is partial synergictic , whereas (1:0.5) and (1:1) ratios has FICI 0.5 and 0.375 which are borderline synergistic and synergistic respectively so the synergistic range was between 0.781 µg/mL and 0.39 µg/mL. The antifungal activity of this combination was good.