Evaluation, in vitro, du potentiel du chitosane pour la lutte contre les champignons responsables des Onychomycoses à Constantine

Abstract

Onychomycosis are frequent, contagious, benign and chronicnail fungal infections. Dermatophytes are considered as the most implicated pathogens but molds and yeasts can also be colonizersor contaminantsagents. Onychomycosis are often observed at an advanced age and an evolved stage, making their treatment long and difficult because of the lack of less or non-toxic molecules used at therapeutic doses. In this context, the main objective of the study was to produce, from Rhizopusoryzae strain, an FDA-approved biopolymer: the chitosan. And evaluate its antifungal activity on the species responsible for onychomycosis in Constantine. 298 samples of infected nails were collected at the laboratory of Mycology and Parasitology of CHUC and analyzed using conventional diagnosis (direct observation and culture) and molecular RT-PCR methods (panfungique-PCR, pandermatophyte- PCR). The results obtained showed that T.rubrum was the predominant species. However, a varietyTrichophytonrubrum var. raubitschekii was identified for the first time in Algeria. As for the synthesized chitosan, its characterization by FTIR and titration revealed a good quality with a slightly higher degree of deacetylation than that of commercial chitosan. Furthermore, demonstration of antifungal activity on the most incriminated species in onychomycoses revealed a significant effect with MICs of 2.5, 1.25 and 0.62mg / ml on T. rubrum, T.rubrum var. raubitschekii and T.interdigitale,respectively. These results could open the way to new therapeutic perspectives, not only against dermatophytes but probably against other fungal agents.