Chemical composition and antifungal potential of Iranian propolis against Candida krusei strains

Abstract

Propolis is known to have biological properties against numerous microorganisms of clinical interest. This is important, because all Candida krusei (C. krusei) isolates are resistant to azole drugs. The aims of this study were to determine the chemical composition and antifungal efficacy of Iranian propolis against C. krusei strains isolated from patients with cutaneous and mucosal candidiasis. Ethanolic extract of propolis (EEP) was prepared from propolis originating from Mazandaran province, and submitted to chemical analysis by high-resolution gas chromatography coupled to mass spectrometry. Additionally, the EEP was tested for its ability to inhibit yeasts by determination of the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) using broth microdilution method (M27-A3 protocol) with some modifications. Phenolic acids (78.2%) were the major components of Iranian propolis. The EEP exhibited MIC values ranging from 2 to 20 mg/ml and MFC values between 4 and 25 mg/ml. The most fungal susceptibility was associated with the nail isolates (mean MIC value: 7.8 mg/ml), followed by the oral isolates (mean MIC value: 9.7 mg/ml) and vaginal isolates (mean MIC value: 11.7 mg/ml). The results showed that Iranian propolis has strong anti-C. krusei activity and should be considered as a promising candidate to treat nail, oral and vaginal candidiasis.