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1.
Nat Prod Res ; 37(12): 2037-2042, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35997245

RESUMO

Coriolopsis rigida was isolated as an endophytic fungus from the medicinal plant Cochlospermum regium, and their production of secondary metabolites has not yet been investigated. Thus, the endophyte was cultivated on rice solid media to evaluate its ability to produce bioactive compounds and then the chloroform extract was obtained. Two phenolic compounds, tyrosol (1) and a new natural product p-hydroxyphenylacetamide (2), were isolated from the extract. The structures of the compounds were elucidated mainly by NMR. The extract showed potent antioxidant activity with an efficient concentration (EC50) value of 0.33 mg mL-1. Additionally, demonstrated allelopathic activity inhibited the seedling growth of Lactuca sativa L. and Raphanus sativus L. by 63% and 55%, respectively.


Assuntos
Plantas Medicinais , Polyporaceae , Fungos , Extratos Vegetais/farmacologia
2.
PLoS One ; 17(10): e0275002, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36190979

RESUMO

Investigating the chemical diversity of natural products from tropical environments is an inspiring approach to developing new drug candidates for neglected tropical diseases (NTDs). In the present study, phenotypic screenings for antiprotozoal activity and a combination of computational and biological approaches enabled the identification and characterization of four cytochalasins, which are fungal metabolites from Brazilian biodiversity sources. Cytochalasins A-D exhibited IC50 values ranging from 2 to 20 µM against intracellular Trypanosoma cruzi and Leishmania infantum amastigotes, values comparable to those of the standard drugs benznidazole and miltefosine for Chagas disease and leishmaniasis, respectively. Furthermore, cytochalasins A-D reduced L. infantum infections by more than 80% in THP-1 cells, most likely due to the inhibition of phagocytosis by interactions with actin. Molecular modelling studies have provided useful insights into the mechanism of action of this class of compounds. Furthermore, cytochalasins A-D showed moderate cytotoxicity against normal cell lines (HFF-1, THP-1, and HepG2) and a good overall profile for oral bioavailability assessed in vitro. The results of this study support the use of natural products from Brazilian biodiversity sources to find potential drug candidates for two of the most important NTDs.


Assuntos
Antiprotozoários , Produtos Biológicos , Trypanosoma cruzi , Actinas , Antiprotozoários/química , Produtos Biológicos/farmacologia , Citocalasinas , Descoberta de Drogas , Humanos , Doenças Negligenciadas/tratamento farmacológico
3.
Rev Soc Bras Med Trop ; 55: e00182022, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36287467

RESUMO

BACKGROUND: Aedes aegypti is the primary vector of viruses, such as Zika, chikungunya, yellow fever, and dengue. In this context, a biomonitored chemical study was conducted to evaluate the activity of the crude extract of the endophytic fungus Phomopsis sp. against the larvae of Aedes aegypti. METHODS: Crude extract, fractions, and isolated substances were evaluated in in-vitro assays against third-stage larvae of Aedes aegypti. RESULTS: We isolated 3-nitropropionic acid with an LC50 of 15.172 ppm and LC90 of 18.178 ppm after 24 hours of larval exposure. CONCLUSIONS: The results indicated that 3-nitropropionic acid exerted larvicidal activity.


Assuntos
Aedes , Anopheles , Culex , Inseticidas , Infecção por Zika virus , Zika virus , Animais , Phomopsis , Inseticidas/farmacologia , Extratos Vegetais , Mosquitos Vetores , Larva
4.
Nat Prod Res ; 36(15): 3999-4002, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33663291

RESUMO

Endophytic fungi are biodiverse and alternative source of bioactive compounds, due their different abilities of genetic expression and alteration of biosynthetic pathway when submitted to different culture conditions. The metabolic profile of three different crude extracts (A, B and C), obtained from the endophytic fungus Asordaria conoidea, were evaluated by HPLC and 1H NMR. Antioxidant and allelochemical activity were also evaluated. OSMAC diversified the metabolic production, mainly in the solid culture, where the tyrosol, 4-hydroxybenzaldehyde, 2-phenylacetamide and vanillic acid were isolated. The structures of the compounds were elucidated mainly by NMR. Extracts had antioxidant potential, however, only Extract C showed allelochemical activity, as inhibition of 65.5% in growth. This study confirms the efficiency of the OSMAC platform in producing extracts of different properties and compounds. Herein the A. conoidea was isolated for the first time as an endophytic microorganism.


Assuntos
Feromônios , Sordariales , Antioxidantes/farmacologia , Fungos , Compostos Orgânicos
5.
Rev. Soc. Bras. Med. Trop ; 55: e0018, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1406967

RESUMO

ABSTRACT Background: Aedes aegypti is the primary vector of viruses, such as Zika, chikungunya, yellow fever, and dengue. In this context, a biomonitored chemical study was conducted to evaluate the activity of the crude extract of the endophytic fungus Phomopsis sp. against the larvae of Aedes aegypti. Methods: Crude extract, fractions, and isolated substances were evaluated in in-vitro assays against third-stage larvae of Aedes aegypti. Results: We isolated 3-nitropropionic acid with an LC50 of 15.172 ppm and LC90 of 18.178 ppm after 24 hours of larval exposure. Conclusions: The results indicated that 3-nitropropionic acid exerted larvicidal activity.

6.
Fitoterapia ; 141: 104466, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31870948

RESUMO

Curvularia lunata, isolated from the capitula of Paepalanthus chiquitensis (Eriocaulaceae), was cultured in potato dextrose broth (PDB) medium. The ethyl acetate extract yielded two new spirocyclic γ-lactams (3 and 4), and five known compounds, namely: triticones E (1) and F (2), 5-O-methylcurvulinic acid (5), curvulinic acid (6) and curvulin (7). Their structures were elucidated by spectroscopic analysis and by the comparison with literature data. Besides, a computational study was used to elucidate the absolute configuration of the C - 3' in the compounds (3) and (4). The extract and the compounds (1 and 2), (6) and (7) were assayed against gram-positive and gram-negative bacteria and fluconazole-resistant yeast. The triticones (1) and (2) showed good antibacterial activity for Escherichia coli, with a minimum inhibitory concentration of 62.5 µg/mL.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Ascomicetos/química , Lactamas/química , Antibacterianos/química , Antifúngicos/química , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular
7.
Magn Reson Chem ; 57(8): 458-471, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30993742

RESUMO

Traditionally, the screening of metabolites in microbial matrices is performed by monocultures. Nonetheless, the absence of biotic and abiotic interactions generally observed in nature still limit the chemical diversity and leads to "poorer" chemical profiles. Nowadays, several methods have been developed to determine the conditions under which cryptic genes are activated, in an attempt to induce these silenced biosynthetic pathways. Among those, the one strain, many compounds (OSMAC) strategy has been applied to enhance metabolic production by a systematic variation of growth parameters. The complexity of the chemical profiles from OSMAC experiments has required increasingly robust and accurate techniques. In this sense, deconvolution-based 1 HNMR quantification have emerged as a promising methodology to decrease complexity and provide a comprehensive perspective for metabolomics studies. Our present work shows an integrated strategy for the increased production and rapid quantification of compounds from microbial sources. Specifically, an OSMAC design of experiments (DoE) was used to optimize the microbial production of bioactive fusaric acid, cytochalasin D and 3-nitropropionic acid, and Global Spectral Deconvolution (GSD)-based 1 HNMR quantification was carried out for their measurement. The results showed that OSMAC increased the production of the metabolites by up to 33% and that GSD was able to extract accurate NMR integrals even in heavily coalescence spectral regions. Moreover, GSD-1 HNMR quantification was reproducible for all species and exhibited validated results that were more selective and accurate than comparative methods. Overall, this strategy up-regulated important metabolites using a reduced number of experiments and provided fast analyte monitor directly in raw extracts.


Assuntos
Técnicas de Cultura de Células/métodos , Citocalasina D/metabolismo , Ácido Fusárico/biossíntese , Metabolômica/métodos , Nitrocompostos/metabolismo , Propionatos/metabolismo , Ascomicetos/isolamento & purificação , Ascomicetos/metabolismo , Citocalasina D/análise , Ácido Fusárico/análise , Nitrocompostos/análise , Propionatos/análise , Espectroscopia de Prótons por Ressonância Magnética
8.
Molecules ; 19(11): 19243-52, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25421415

RESUMO

In this study, eight endophytic fungi were isolated from the leaves, stems and roots of Michelia champaca. The isolates were screened and evaluated for their antifungal, anticancer and acetylcholinesterase (AChE) inhibitory activities. All of the extracts exhibited potent activity against two evaluated phytopathogenic fungi. Chemical investigation of EtOAc extracts of the endophytic fungus Colletotrichum gloeosporioides resulted in the isolation of one new compound, 2-phenylethyl 1H-indol-3-yl-acetate (1), and seven known compounds: uracil (2), cyclo-(S*-Pro-S*-Tyr) (3), cyclo-(S*-Pro-S*-Val) (4), 2(2-aminophenyl)acetic acid (5), 2(4-hydroxyphenyl)acetic acid (6), 4-hydroxy- benzamide (7) and 2(2-hydroxyphenyl)acetic acid (8). All of the compound structures were elucidated using 1D and 2D NMR and MS analyses. The antifungal and AChE inhibitory activities of compounds 1-8 were evaluated in vitro. Compound 1 exhibited promising activity against Cladosporium cladosporioides and C. sphaerospermum that was comparable to that of the positive control nystatin.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Colletotrichum/química , Fungos/efeitos dos fármacos , Magnoliaceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Cladosporium/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química
9.
Molecules ; 19(5): 6597-608, 2014 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-24858094

RESUMO

Chemical investigation of an acetonitrile fraction from the endophytic fungus Phomopsis sp. led to the isolation of the new natural product 2-hydroxy-alternariol (7) together with the known compounds cytochalasins J (1) and H (2), 5'-epialtenuene (3) and the mycotoxins alternariol monomethyl ether (AME, 4), alternariol (AOH, 5) and cytosporone C (6). The structure of the new compound was elucidated by using 1-D and 2-D NMR (nuclear magnetic resonance) and high resolution mass spectrometry. The cytochalasins J (1) and H (2) and AOH (5) exhibited potent inhibition of the total ROS (reactive oxygen species) produced by stimulated human neutrophils and acted as potent potential anti-inflammatory agents. Moreover, cytochalasin H (2) demonstrated antifungal and acetylcholinesterase enzyme (AChE) inhibition in vitro.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antifúngicos/farmacologia , Ascomicetos/metabolismo , Anti-Inflamatórios não Esteroides/química , Antifúngicos/química , Antioxidantes/química , Antioxidantes/farmacologia , Ascomicetos/química , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Citocalasinas/química , Citocalasinas/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Endófitos/metabolismo , Humanos , Lactonas , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Micotoxinas/química , Micotoxinas/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Metabolismo Secundário , Senna/microbiologia , Sesquiterpenos/química , Sesquiterpenos/farmacologia
10.
Braz. j. microbiol ; 44(3): 923-926, July-Sept. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-699782

RESUMO

A sensitive and efficient colorimetric method was optimized for detection of esterase enzymes produced by endophytic fungi for development of High-Throughput Screening (HTS). The fungi were isolated and obtained previously from plant species of Cerrado and Atlantic Forest located in areas of environmental preservation in the State of Sao Paulo / Brazil, as part of the project "Chemical and biological prospecting endophytic fungi associated to plant species of Cerrado and Atlantic Forest". The compounds ethyl butyrate, ethyl acetate and methyl propionate were used as standards esters which were hydrolyzed by extracellular enzyme from endophytic fungi (EC. 3.1.1.1 -carboxylesterases) for production of carboxylic acids. Thus, the reduction of the pH increases the protonated indicator concentration (bromothymol blue), changing the color of the reaction medium (from blue to yellow), that can be observed and measured by spectrophotometry at 616 nm. The methodology with acid-base indicator was performed on 13 microorganisms, aiming Periconia atropurpurea asapotential source of esterase for biotransformation of short chain esters. The results also evidenced that this methodology showed to be efficient, fast, cheap, having low consumption of reagents and easy development, and can be applied to screen carboxylic-ester hydrolases in a large number of microorganisms.


Assuntos
Colorimetria/métodos , Endófitos/enzimologia , Esterases/análise , Fungos/enzimologia , Acetatos/metabolismo , Brasil , Butiratos/metabolismo , Fungos/isolamento & purificação , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Plantas/microbiologia , Propionatos/metabolismo
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