In Vitro Anti-Fungal Activity of the Essential Oil and Plant Extract Mixture of a Skin Cream
The investigational skin cream (PID 02027030, produced by Oystershell, Belgium) is sold as a cosmetic product for dogs, cats, and horses to be used on skin abrasions, hot spots, etc. It contains a mixture of essential oils and plant extracts (8.25% v/w) in a non-natural base. To determine if the product could be useful in promoting healing in the case of skin infections, an in vitro study was conducted to determine the anti-fungal activity of the cream. Due to difficulties of using the formulated cream in a water-based test, the mixture of oils and extracts were used. A broth microdilution method was used to determine the minimum inhibition concentration (MIC) (read visually and with a spectrometer) and minimum fungicidal concentration (MFC) of the oil/extract mixture against three strains each of Candida albicans, Malassezia pachydermatis, Microsporum canis, and Trichophyton mentagrophytes. Each test was repeated 3 times. The MIC 80% values ranged from 0.032 to 1% concentration (visual) and 0.032 to 2% concentration (spectrometer), with more activity against C. albicans. The MFC values ranged from 0.25 to >2% concentration with more inhibition against M. canis.