Antidermatophytic Properties of Ar-Turmerone, Turmeric Oil, and Curcuma longa Preparations

Curcuma longa L. or turmeric of the family Zingiberaceae is widely used in Thai traditional medicines for the treatment of rash, itching, tinea, and ringworm. Previous studies on turmeric oil reported effective antifungal activity against dermatophytes, a group of fungi that causes skin diseases. In this study, turmeric creams containing 6 and 10%？w/w turmeric oil were prepared and tested against clinical strains of dermatophytes using broth dilution technique. Minimum fungicidal concentrations of 6 and 10%？w/w turmeric creams were found to be 312？μg/mL. Ar-turmerone, a major compound separated from turmeric oil, promoted more effective antidermatophytic activity with the MICs of 1.56–6.25？μg/mL, compared to 3.90–7.81？μg/mL of standard ketoconazole. The results indicated that 6%？w/w turmeric oil in the cream was suitable to be formulated as antidermatophytic preparation. Further research should be done on long-term chemical and antifungal stabilities of the preparation. 1. Introduction Dermatophytosis (tinea or ringworm) is a prevalent form of fungal infections found in Thailand because of the tropical climate. The infection is caused by a group of keratinophilic fungi called dermatophytes. Fungi commonly involved are of the genera Trichophyton, Microsporum, and Epidermophyton. Dermatophytosis can transfer from soil and animals to humans and cause infection on many parts of the body [1, 2]. Historically, Thai traditional medicines containing Curcuma longa have been used for the treatment of dermatophytes. The dry powdered rhizome is mixed with a small volume of water and the mixture is applied onto infected skin [3]. C. longa L. or turmeric is a well-known medicinal plant of the family Zingiberaceae [4]. It has been used for the treatment of skin diseases, rash, itching, tinea and ringworm. Turmeric is a perennial herb with thick and ellipsoid-ovate rhizome with orange cortex inside. It is cultivated easily, wildly distributed in Thailand and other tropical and subtropical countries, and is also famous as a spice and coloring agent [5]. Medicinal uses of the rhizomes arise from volatile oil as a carminative and antifungal activity and yellow curcuminoids for antioxidative and anti-inflammatory properties. Active constituents in turmeric volatile oil are turmerone, atlantone, and zingiberone [6, 7]. Turmeric oil isolated from turmeric rhizome possesses effective antifungal activity against dermatophytes [8, 9]. The creams containing 3–8%？w/w turmeric oil showed similar antidermatophytic activity [10]. To determine a suitable concentration of turmeric oil