In vitro Study and Clinical Trial of Natural Essential Oils and Extract Against Malassezia Species

Lee, Min Young; Na, Eui Young; Yun, Sook Jung; Lee, Seung Chul; Won, Young Ho; Lee, Jee Bum

Abstract

BACKGROUND
Malassezia, a lipophilic yeast, is a causative agent for dandruff and seborrheic dermatitis. Many biological agents have been studied for anti-Malassezia effect but further studies are needed for their clinical application.
OBJECTIVE
The study was conducted to evaluate the inhibitory effect of different natural essential oils and a fruit extract on Malassezia species in an in vitro study and a clinical trial.
METHODS
The antifungal effects of natural essential oils and a fruit extract on Malassezia species (M. furfur and M. sympodialis) were evaluated by measuring the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) and using the disc diffusion method. Natural essential oils of citron seed, lavender, and rosemary and citrus junos fruit extract were used for the in vitro study. The clinical trial was conducted with a shampoo containing four ingredients. A total of 22 subjects used the shampoo every day for 4 weeks and were evaluated using clinical photography, trichoscopy, and sebumeter at baseline, 2 weeks, and 4 weeks after treatment.
RESULTS
Antifungal activity of agents was relatively lower in lavender and rosemary essential oils at MIC and MFC. Disc diffusion method revealed same results. In the clinical trial, the amount of sebum decreased statistically significantly and erythema, dandruff, and lesion extent also improved.
CONCLUSION
The natural essential oils and fruit extract are effective for suppressing Malassezia activity, therefore these might be used as an alternative for treatment of dandruff and seborrheic dermatitis.