In vitro activity of Penicillium chrysogenum antifungal protein (PAF) and its combination with fluconazole against different dermatophytes

Abstract

Strains of five dermatophyte species (Microsporum canis, Microsporum gypseum, Trichophyton mentagrophytes, Trichophyton rubrum and Trichophyton tonsurans) were selected for testing against Penicillium chrysogenum antifungal protein (PAF) and its combination with fluconazole (FCZ). Inhibition of microconidia germination and growth was detected with MICs of PAF ranging from 1.56 to 200 microg ml(-1) when it was used alone, or at constant concentration (100 microg ml(-1)) in combination with FCZ at from 0.25 to 32 microg ml(-1). The MICs for FCZ were found to be between 0.25 and 128 microg ml(-1). PAF caused a fungicidal effect at 200 microg ml(-1) and reduced growth at between 50 and 200 microg ml(-1). Total growth inhibition with fungistatic activity was detected at 64 microg ml(-1) of FCZ for M. gypseum, T. mentagrophytes, and T. tonsurans, and at 32 microg ml(-1) FCZ for M. canis and T. rubrum. PAF and FCZ acted synergistically and/or additively on all of the tested fungi except M. gypseum, where no interactions were detected.