IN-VITRO ANTIFUNGAL ACTIVITY OF SERTACONAZOLE AND BIFONAZOLE AGAINST DERMATOPHYTES

The in vitro antifungal activity of sertaconazole, a new benzothiophen e derivative, was compared with that of bifonazole against 52 dermatop hytes: Epidermophyton floccosum (7), Microsporum canis (9), Microsporu m gypseum; (5), Trichophyton mentagrophytes (14), and Trichophyton rub rum (17). A standardized two-fold dilution method with Sabouraud gluco se broth (pH 5.6) was used. The concentrations bf antifungal drugs ran ged between 40 mu g/ml and 0.03 mu/ml in 96-well microtiter plates. An tifungal agents were dissolved in dimethylsulfoxide (1 mg/ml). Inocula were prepared using 7-14 day cultures on Sabouraud glucose agar to pr ovide suspensions of aerial part of each culture in sterile saline sol utions with Tween 80 between 1.42 x 10(5) colony forming unit (CFU)/ml and 6.6 x 10(6) CFU/ml. Readings were made 7/14 days after incubation at 28 degrees C, and desiccation of liquid medium was avoided. Experi ments were performed in duplicate. Minimal inhibitory concentrations ( MIG) were determined as the lowest drug concentration which inhibits t he growth. The results indicated that sertaconazole (arithmetic mean M IC 0.46 mu g/ml) was statistically more active than bifonazole (arithm etic mean MIC 1.21 mu g/ml). MIC's for sertaconazole were lower (P < 0 .05) than those for bifonazole for each tested species. Epidermophyton floccosum (MIG 0.11 mu g/ml) had the highest susceptibility to sertac onazole, while M. gypseum had the highest MIC (0.87 mu g/ml). These va lues confirm that sertaconazole has an important in vitro activity aga inst the most frequently isolated dermatophytes in human and animal my cology.