The bark of the Phellodendron tree has been used in traditional Chinese medicine for thousands of years. Phellodendron amurense is widely used to treat gastroenteritis, abdominal pain, diarrhea and various inflammatory diseases including arthritis and dermatophytosis. The present study was undertaken to evaluate the antifungal effects of Phellodendron amurense ethanol extract (PAEE) against Trichophyton mentagrophytes in vivo and in vitro. Quantitative analysis revealed that the level of total alkaloids in PAEE was 7.58±0.46 mg/mL. In the in vitro study, the minimal inhibitory concentration (MIC) of PAEE (0.03g/mL) and clotrimazole (0.02 mg/mL) were determined using 1.5% tryptic soya agar. The influence of different doses of PAEE on the growth of T. mentagrophytes was detected by dry weight determination. Moreover, transmission electronic microscopy was performed to observe the effect of PAEE on cell ultrastructure, and it showed that PAEE destroyed the cell membrane of T. mentagrophytes. Furthermore, the dermatophytosis infection model in rabbits with T. mentagrophytes was established for investigating the in vivo effect of PAEE at 10, 50 and 100% concentrations. The findings in all treatment groups demonstrated the inhibitory effects of PAEE against T. mentagrophytes. Therefore, we conclude that PAEE has significant antifungal activity and could be used to treat T. mentagrophytes infections in rabbits.

Key words: Alkaloids, Antifungal, Medicinal plants, Phellodendron chinense, Trichophyton mentagrophytes