Estudo de fungos melanizados em amostras ambientais de áreas rurais do Amazonas e avaliação da sua relação com os fungos melanizados causadores de micoses

Abstract

The melanized fungi are widely distributed in the environment and has been commonly related in human diseases such as Chromoblastomycosis, Phaeomycosis and Eumycetoma, but in the Amazon region, which have a favorable weather for the proliferation of microorganisms, there are few studies about these fungi and little is known about their distribution in this environment and its pathogenic potential. Thus, in this study were studied melanized fungi in environmental samples from rural areas of the Amazon and the relationship of these environmental isolates with melanized fungi that cause mycoses. Environmental samples were obtained in rural areas of Iranduba and Presidente Figueiredo – Amazonas (Brazil). Also entered in the study, clinical specimens deposited in Fungal Collections from Amazonas. Two hundred thirteen samples of various environmental substrates were collected: soil, parts of living plants, decaying plant material and drinking water. Of these samples, 45 isolates were subjected to identification by sequencing the ITS region, 7 species of melanized fungi that were identified have been described in the literature as etiological agents of mycoses in humans: Cladophialophora immunda, Cladosporium sphaerospermum, Cladosporium cladosporioides, Exophiala oligosperma, Exophiala jeanselmei, Hortaea werneckii and Curvularia lunata. Most isolates were obtained from thorns. Some isolates grown at 37°C temperature. The molecular identification of clinical isolates showed similarity with Fonsecaea pedrosoi, Cladosporium sphaerospermum and Knufia epidermidis. Of these clinical specimens, only the species C. sphaerospermum was isolated from the environment. This study shows that the studied environmental substrates are potential sources of infection of melanized fungi that may cause mycoses.