We studied the fungal endophyte community of the leaves of Myracrodruon urundeuva in Brazil along with their potential to produce L-asparaginase. In total, 187 endophytes were isolated. The colonization rate of leaf fragments from caatinga (10.41 %) was lower than those from brejo de altitude (39.58 %). Sequences of ITS rDNA from all endophytes revealed relationships with Ascomycota (Botryosphaeriales, Chaetothyriales, Diaporthales, Eurotiales, Glomerellales, Hypocreales, and Pleosporales) and Basidiomycota (Polyporales). The most frequent endophytes were members of the genus Diaporthe. Talaromyces was an indicator genus for caatinga while Phyllosticta, Diaporthe, and Colletotrichum were for brejo de altitude. The composition of endophytic fungi in caatinga and brejo de altitude differed significantly, its richness and diversity (H' = 3.41) being significantly higher in brejo de altitude. Diaporthe sp. URM 7793 was the best producer of L-asparaginase (2.41 U/g), followed by Diaporthe sp. URM 7779 (2.00 U/g), Talaromyces sp. URM 7785 (1.91 U/g), and Diaporthe sp. URM 7792 (1.47 U/g). The composition of endophytic fungi assemblages is strongly influenced by the type of ecosystem. In its natural habitat, M. urundeuva harbors an important diversity of endophytes, which could be used to produce L-asparaginase.
The present study reports a new occurrence of Rhinocladiella similis isolated as an endophytic fungus in the Caatinga dry tropical forest in Brazil and describes its antifungal susceptibility. The isolate R. similis URM 7800 was obtained from leaves of the medicinal plant Myracrodruon urundeuva. Its morphological characterization was performed on potato dextrose agar medium and molecular analysis using the ITS rDNA sequence. The antifungal susceptibility profile was defined using the Clinical and Laboratory Standards Institute (CLSI) protocol M38-A2. The colony of isolate URM 7800 showed slow growth, with an olivaceous-gray color and powdery mycelium; in microculture, it showed the typical features of R. similis. In the antifungal susceptibility test, isolate URM 7800 showed high minimal inhibitory concentration (MIC) values for amphotericin B (>16 μg/mL), voriconazole (16 μg/mL), terbinafine (>0.5 μg/mL), and caspofungin (>8 μg/mL), among other antifungal drugs. Pathogenic melanized fungi are frequently isolated in environments where humans may be exposed, and these data show that it is essential to know if these isolates possess antifungal resistance.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.