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Updated: Feb 5, 2026

Establishing Fungal Entomopathogens as Endophytes: Towards Endophytic Biological Control
Published on: April 11, 2013
Two new usnic acid derivatives from the endophytic fungus Mycosphaerella sp
Djalma M de Oliveira1, Cristiane B Pereira2, Graziele Mendes2
1Department of Sciences and Technologies, State University of Bahia Southwest, Jequié, Bahia, Brazil.
Abstract:
The endophytic fungus Mycosphaerella sp. (UFMGCB2032) was isolated from the healthy leaves of Eugenia bimarginata, a plant from the Brazilian savanna. Two novel usnic acid derivatives, mycousfuranine (1) and mycousnicdiol (2), were isolated from the ethyl acetate extract, and their structure was elucidated by NMR and MS analyses. Compounds 1 and 2 exhibited moderate antifungal activities against Cryptococcus neoformans and Cryptococcus gattii, each with minimum inhibitory concentration values of 50.0 μg/mL and 250.0 μg/mL, respectively.
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