Study On The Antifungal Activity Of Ellagic Acid Against Trichophyton Rubrum In Vitro And Its Mechanism

Objective: In order to study the antifungal effects of Ellagic Acid in the Trichophyton rubrum(T.rubrum)ultrastructure,apoptosis activity and ergosterol biosynthesis.Try to explore the potential mechanism of EA.Methods: 1)Applied the standard approved by the National Committee for Clinical Laboratory Standards(NCCLS): Reference Method for Broth Dilution Antifungal Susceptibility Testing of Filamentous Fungi(M38-A),investigated the MICs of EA against 4strains of common clinical fungi,and determined its antifungus spectrum and screened sensitive strains.According to those MICs,we tested the inhibitory rate of EA on T.rubrum by using Cell Counting kit(CCK-8).2)Treated T.rubrum with EA,and observed the cell surface structures by Scanning Electron Microscope(SEM).3)The cell apoptosis effects of EA in T.rubrum determined by using Flow Cytometry Instrument Technique(FCIT).4)Studied the gene expressions of EA on SUB1,MEP4,ERG11 genes in T.rubrum related to ergosterol synthesis and pathway.Results: 1)The mean MICs of EA against T.rubrum and T.mentagrophytes were higher than 64μg·mL-1.The mean MICs of EA against C.albicans,C.glabrata were higher than 256μg·mL-1.2)Being observed by SEM the T.rubrum cell surface wrinkled,folded and cell broke after being treated with EA.3)The cell apoptosis analysis showed that in T.rubrum treated with EA.The quantity of ergosterol in T.rubrum treated with EA 128μg·mL-1 decreased by 53.1%compared with growth control.The ergosterol content had a dose-dependent manner on EA concentration.4)The RT-PCR test results showed that in T.rubrum treated with low and middle concentration of EA,and there were statistical significance(P<0.05,growth control).Conclusion: 1)EA has remarkable antifungal activity against the dermatophytes in vitro T.rubrum is more sensitive to EA than Candida.The antifungal susceptibility was Trichophyton rubrum>Trichophyton mentagrophytes>Candida albicans>Candida parapsilosis.The mechanism of antifungal action of EA is may related to upgrade the ERG6 expression in order to decrease the speed of C-14 synthesis process.