The impact of lemongrass, oregano, and thyme essential oils on Candida albicans’ virulence factors

Abstract

Increased systemic infections and growing resistance of Candida species in immunosuppressed people have prompted research for additional treatment options. The purpose of this study was to investigate the potential of lemongrass, oregano, and thyme essential oils tested individually, combined, and combined with the antifungal agents fluconazole and caspofungin to kill Candida albicans isolates in a controlled laboratory setting. A quantitative design was used to analyze the experimental data collected and investigate risk factors related to age, gender, race, and co-morbidities. Kill rates of lemongrass, oregano, and thyme essential oils individually and combined, kill rates of fluconazole, caspofungin, and the kill rates when the antifungals were each combined with the three essential oils were compared using 117 isolates recovered from bloodstream infections between January 2009 through August 1, 2017. There were statistically significant increases in kill rates when the isolates were exposed to any of the combinations of essential oils tested. Data on the covariates age, gender, race, and co-morbidities were assessed for risk factors related to Candida albicans bloodstream infections. The age group 25-34, kidney failure, and solid organ tumor cancer, were all statistically significantly associated with an increased risk for Candida albicans bloodstream infections and multiple organ failure was negatively associated with the risk. Through the use of essential oils, the ability to reduce the number of patients becoming infected with life-threatening yeast infections could not only reduce mortality but also reduce the costs associated with serious infections.