Papers by Emerson C Barbosa
Natural products are potential alternat ive sources for the development of antiviral drugs for de... more Natural products are potential alternat ive sources for the development of antiviral drugs for dengue treatment of, as well as for other diseases caused by viruses of the Flaviviridae family or even caused by a br oad spectrum of viruses. In this study, were performed an in vitro screening for activity against Dengue virus (DENV-2) of 3101 extracts fr om plants and fungi belonging to Fiocruz Minas extract sample collection. To this end, BHK-21 cells infected with DENV-2 were simultaneously treated with 25 μg/mL of extract and t he results analyzed by two methods: observing the degree of inhibiti on of DENV cytopathic effect (CPE) by optical microscopy and also by analysis of cell viability MTT colorimetric assay. Among the 3101 extracts tested, 115 extrac ts showed antiviral activity against DENV-2 and were selected for determination of its half maximal effective concentration (EC 50 ). Fifty-five of these extracts ar e taken from plants belonging to 20 different families: Amaryllid...
Emerging Infectious Diseases, Aug 1, 2022
We report the first confirmed case of DENV-2 Cosmopolitan genotype isolated from a male patient f... more We report the first confirmed case of DENV-2 Cosmopolitan genotype isolated from a male patient from Aparecida de Goiania, Goias state, Midwest Brazil. Using nanopore sequencing, and phylogenetic analyses our findings provide the first preliminary insight regarding the introduction of this emerging genotype in Brazil and South America.
Virology Journal, 2022
Background The worldwide epidemics of diseases as dengue and Zika have triggered an intense effor... more Background The worldwide epidemics of diseases as dengue and Zika have triggered an intense effort to repurpose drugs and search for novel antivirals to treat patients as no approved drugs for these diseases are currently available. Our aim was to screen plant-derived extracts to identify and isolate compounds with antiviral properties against dengue virus (DENV) and Zika virus (ZIKV). Methods Seven thousand plant extracts were screened in vitro for their antiviral properties against DENV-2 and ZIKV by their viral cytopathic effect reduction followed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method, previously validated for this purpose. Selected extracts were submitted to bioactivity-guided fractionation using high- and ultrahigh-pressure liquid chromatography. In parallel, high-resolution mass spectrometric data (MSn) were collected from each fraction, allowing compounds into the active fractions to be tracked in subsequent fractionation procedures....
Fungal Biology, 2020
We recovered 195 fungal isolates from the sediments of different lakes in the Antarctic Peninsula... more We recovered 195 fungal isolates from the sediments of different lakes in the Antarctic Peninsula, which were screened to detect bioactive compounds. Forty-two taxa belonging to the phyla Ascomycota, Basidiomycota, and Mortierellomycota were identified. Thelebolus globosus, Antarctomyces psychrotrophicus, Pseudogymnoascus verrucosus, Vishniacozyma victoriae, and Phenoliferia sp. were found to be the most prevalent. The fungal assemblages showed high diversity and richness, but low dominance values. However, the diversity indices and fungal distribution ranged according to the different lake sediments. Sixty fungal extracts displayed at least one biological activity against the evaluated targets. Among them, Pseudogymnoascus destructans showed selective trypanocidal activity, Cladosporium sp. 1 and Trichoderma polysporum showed antifungal activity, and Pseudogymnoascus appendiculatus and Helotiales sp. showed high herbicidal activity. We detected a rich and diverse fungal community composed of cold cosmopolitan and psychrophilic endemic taxa recognized as decomposers, symbiotics, pathogens, and potential new species, in the sediments of Antarctic lakes. The dynamics and balance of this fungal community represents an interesting aquatic web model for further ecological and evolutionary studies under extreme conditions and potential climate changes in the regions. In addition, we detected fungal taxa and isolates able to produce bioactive compounds that may represent the source of prototype molecules for applications in medicine and agriculture.
Neotropical Endophytic Fungi, 2021
Extremophiles, 2020
In this study, we accessed culturable fungal assemblages present in the sediments of three lakes ... more In this study, we accessed culturable fungal assemblages present in the sediments of three lakes potentially impacted anthropogenically in the Fildes Peninsula, King George Island, Antarctica and identified 63 taxa. Cladosporium sp. 2, Pseudeurotium hygrophilum , and Pseudogymnoascus verrucosus were recovered from the sampled sediments of all lakes. High concentrations of metals and the lowest fungal diversity indices were detected in the sediments of the Central Lake, which can be influenced by human activities due to their proximity to research stations to those of the other two lakes, which were far from the Antarctic stations. At least one type of biological activity was demonstrated by 40 fungal extracts. Among these, P. hygrophilum , P. verrucosus , Penicillium glabrum , and Penicillium solitum demonstrated strong trypanocidal, herbicidal, and antifungal activities. Our results suggest that an increase of the anthropogenic activities in the region might have affected the microbial diversity and composition. In addition, the fungal diversity in these lakes may be a useful model to study the effect of anthropogenic activities in Antarctica. We isolated a diverse group of fungal taxa from Antarctic lake sediments, which have the potential to produce novel compounds for the both the medical and agriculture sectors.
Extremophiles, 2019
We accessed the culturable mycobiota present in marine sediments at different depths in Antarctic... more We accessed the culturable mycobiota present in marine sediments at different depths in Antarctica Ocean. Acremonium fusidioides , Penicillium allii-sativi , Penicillium chrysogenum , Penicillium palitans , Penicillium solitum , and Pseudogymnoascus verrucosus were identified. Penicillium allii-sativi was the dominant species. At least one isolate of each species was capable to present antifungal, trypanocidal, leishmanicidal, antimalarial, nematocidal, or herbicidal activities. Penicillium produced extracts with strong trypanocidal and antimalarial activities, and the extracts of P. solitum and P. chrysogenum demonstrated strong antimalarial activities. Acremonium fusidioides and P . verrucosus displayed strong selective herbicidal properties. The 1 H NMR signals for extracts of A . fusidioides , P . chrysogenum , and P . solitum indicated the presence of highly functionalized secondary metabolites, which may be responsible for the biological activities detected. In the deep marine Antarctic sediments, we detected fungal assemblages in which the Penicillium species were found to be dominant and demonstrated capabilities to survive and/or colonise that poly-extreme habitat. Penicillium being a polyextremophile Antarctic species, exhibited strong biological activities and the presence of aromatic compounds in its extracts may indicate that they are wild ancient strains with high genetic and biochemical potentials that enable them to produce bioactive compounds which can be researched in further studies and used in the chemotherapy of neglected tropical diseases as well as in agriculture.
Environmental microbiology, Jan 31, 2015
This study assessed the diversity of cultivable rock-associated fungi from Atacama Desert. Eighty... more This study assessed the diversity of cultivable rock-associated fungi from Atacama Desert. Eighty-one fungal isolates obtained were identified as 21 species from Ascomycota, sequencing different regions of fungal DNA. Cladosporium halotolerans, Penicillium chrysogenum and Penicillium citrinum were the most frequent species, which occur at least in four different altitudes. The diversity and similarity indices ranged in the fungal communities across the latitudinal gradient. The Fisher-α index displayed the higher values for the fungal communities obtained from the siltstone and fine matrix of pyroclastic rocks with finer grain size, which are more degraded. Twenty-one fungal extracts displayed activity against the different targets screened. The extract of Penicillium chrysogenum afforded the compounds α-linolenic acid and ergosterol endoperoxide, which were active against Cryptococcus neoformans and methicillin-resistance Staphylococcus aureus, respectively. Our study represents th...
Extremophiles, 2015
understanding eukaryotic survival in cold-arid oligotrophic soils. We hypothesize that detailed f... more understanding eukaryotic survival in cold-arid oligotrophic soils. We hypothesize that detailed further investigations may provide a greater understanding of the evolution of Antarctic fungi and their relationships with other organisms described in that region. Additionally, different wild pristine bioactive fungal isolates found in continental Antarctic soil may represent a unique source to discover prototype molecules for use in drug and biopesticide discovery studies.
Extremophiles : life under extreme conditions, Jan 13, 2018
Molecular biology techniques were used to identify 218 fungi from soil samples collected from fou... more Molecular biology techniques were used to identify 218 fungi from soil samples collected from four islands of Antarctica. These consisted of 22 taxa of 15 different genera belonging to the Zygomycota, Ascomycota, and Basidiomycota. Mortierella, Antarctomyces, Pseudogymnoascus, and Penicillium were the most frequently isolated genera and Penicillium tardochrysogenum, Penicillium verrucosus, Goffeauzyma gilvescens, and Mortierella sp. 2 the most abundant taxa. All fungal isolates were cultivated using solid-state fermentation to obtain their crude extracts. Pseudogymnoascus destructans, Mortierella parvispora, and Penicillium chrysogenum displayed antiparasitic activities, whilst extracts of P. destructans, Mortierella amoeboidea, Mortierella sp. 3, and P. tardochrysogenum showed herbicidal activities. Reported as pathogenic for bats, different isolates of P. destructans exhibited trypanocidal activities and herbicidal activity, and may be a source of bioactive molecules to be conside...
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Papers by Emerson C Barbosa