Antimycobacterial and antimalarial activities of endophytic fungi associated with the ancient and narrowly endemic neotropical plant Vellozia gigantea from Brazil

Abstract

BACKGROUND Endophytic fungi, present mainly in the Ascomycota and Basidiomycota phyla, are associated with different plants and represent important producers of bioactive natural products. Brazil has a rich biodiversity of plant species, including those reported as being endemic. Among the endemic Brazilian plant species, Vellozia gigantea (Velloziaceae) is threatened by extinction and is a promising target to recover endophytic fungi.OBJECTIVE The present study focused on bioprospecting of bioactive compounds of the endophytic fungi associated with V. gigantea, an endemic, ancient, and endangered plant species that occurs only in the rupestrian grasslands of Brazil.METHODS The capability of 285 fungal isolates to produce antimicrobial and antimalarial activities was examined. Fungi were grown at solid-state fermentation to recover their crude extracts in dichloromethane. Bioactive extracts were analysed by chromatographic fractionation and NMR and displayed compounds with antimicrobial, antimycobacterial, and antimalarial activities.FINDINGS Five fungi produced antimicrobial and antimalarial compounds. Extracts of Diaporthe miriciae showed antifungal, antibacterial, and antimalarial activities; Trichoderma effusum displayed selective antibacterial activity against methicillin-resistant Staphylococcus aureus and Mycobacterium intracellulare; and three Penicillium species showed antibacterial activity. D. miriciae extract contained highly functionalised secondary metabolites, yielding the compound epoxycytochalasin H with high antimalarial activity against the chloroquine-resistant strain of Plasmodium falciparum, with an IC50 approximately 3.5-fold lower than that with chloroquine.MAIN CONCLUSION Our results indicate that V. gigantea may represent a microhabitat repository hotspot of potential fungi producers of bioactive compounds and suggest that endophytic fungal communities might be an important biological component contributing to the fitness of the plants living in the rupestrian grassland.

Bioprospecting and Structure of Fungal Endophyte Communities Found in the Brazilian Biomes, Pantanal, and Cerrado

“…Diaporthe was the dominant genus in both plants (Figure 3 ; Table S1 ). This genus has also been described as dominant in S. adstringens by Carvalho et al ( 2012 ) and is widely distributed in different plants of several biomes, such as the Pantanal (Hokama et al, 2017 ; Pietro-Souza et al, 2017 ), Mangrove forest (de Souza Sebastianes et al, 2013 ), Atlantic Rainforest (Correia et al, 2017 ), Cerrado and Caatinga (Ferreira et al, 2012 ; Lisboa et al, 2013 ). The ability of Diaporthe species to colonize different plants may result from the produced metabolites that bypass the plants defenses, or even by acting on host development and defense against plant pathogens (Nicoletti and Fiorentino, 2015 ; Santos et al, 2016 ; Tahir et al, 2017 ).…”

Antiplasmodial natural products: an update

“…The endophytic fungus Diaporthe miriciae produced epoxycytochalasin H ( 419 ) with potent antiplasmodial activity against D6 and W2 parasite strains. The compound was not cytotoxic against Vero cells, indicating that the toxicity to the parasite is selective [258].…”

Elucidating Mechanisms of Endophytes Used in Plant Protection and Other Bioactivities With Multifunctional Prospects

“…Munumbicins E-4 and E-5 produced by endophytic fungi showed antimalarial activity, which was found to have double the effect of chloroquine (Suryanarayanan et al, 2003). An endophytes Diaporthe miriciae was found to produce a secondary metabolite called epoxycytochalasin H which expresses strong antimalarial inhibition against a strain of Plasmodium falciparum that is resistant to chloroquine (Ferreira et al, 2017). A report by Ateba et al (2018) showed that endophyte species Paecilomyces lilcinus and Penicillium Janthinellum are storehouse of novel metabolites that are active against Plasmodium falciparum and promising in the cure of malaria.…”