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1.
Arch Pharm (Weinheim) ; 355(4): e2100441, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35099085

RESUMO

Microbial strains isolated from extreme and understudied environments, such as caves, are still poorly investigated for the production of bioactive secondary metabolites. Investigation of the ethyl acetate extract from the growth medium produced by the soil-derived fungus Aspergillus sp. SDC28, isolated from a Brazilian cave, yielded two anthraquinones: versicolorin C (1) and versiconol (2). The complete assignment of nuclear magnetic resonance and mass spectroscopic data of 1 and 2 was performed for the first time. Moreover, the yet unreported absolute configuration of both compounds was unambiguously established by analysis of experimental and theoretical electronic circular dichroism data. Vibrational circular dichroism was also applied to confirm the absolute stereochemistry of 2. Compounds 1 and 2 showed cytotoxic activity against human ovarian cancer cells (OVCAR3).


Assuntos
Cavernas , Neoplasias Ovarianas , Antraquinonas/farmacologia , Apoptose , Aspergillus/química , Aspergillus/metabolismo , Brasil , Linhagem Celular Tumoral , Dicroísmo Circular , Feminino , Humanos , Estrutura Molecular , Oligodesoxirribonucleotídeos , Solo , Relação Estrutura-Atividade , Tionucleotídeos
2.
Braz J Microbiol ; 51(3): 989-997, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32333271

RESUMO

Fungi in the genus Trichoderma are notorious producers of secondary metabolites with diverse applications, such as antibacterial, antifungal, and plant growth-promoting properties. Peptaibols are linear peptides produced by such fungi, with more than 440 compounds described to date, including tricholongins, longibrachins, trichobrachins, and trichovirins. Peptaibols are synthesized by non-ribosomal peptide synthetases and they have several biological activities. Our research group isolated four peptaibols (6DP2, 6DP3, 6DP4, and 6DP5) with antifungal activity against the plant pathogen Colletotrichum gloeosporioides and the proteasome (a cancer chemotherapy target) from Trichoderma sp. P8BDA1F1, an endophytic fungus from Begonia venosa. The ethyl acetate extract of this endophyte showed activity of 6.01% and 75% against C. gloeosporioides and the proteasome, respectively. The isolated compounds were identified by MS/MS and compared to literature data, suggesting the presence of trilongins BI, BII, BIII, and BIV, which are peptaibols containing 20 amino acid residues. The minimum inhibitory concentration against C. gloeosporioides was 40 µM for trilongin BI, 320 µM for trilongin BII, 160 µM for trilongin BIII, and 310 µM for trilongin BIV. BI-BIV trilongins inhibited proteasome ChTL activity, with IC50 values of 6.5 ± 2.7; 4.7 ± 1.8; 6.3 ± 2.2; and 2.7 ± 0.5 µM, respectively. The compounds were tested ex vivo against the intracellular amastigotes of Leishmania (L.) infantum but showed no selectivity. It is the first report of trilongins BI-BIV with antifungal activity against C. gloeosporioides and the proteasome target.


Assuntos
Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Begoniaceae/microbiologia , Peptaibols/farmacologia , Trichoderma/química , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Colletotrichum/efeitos dos fármacos , Endófitos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Peptaibols/química , Peptaibols/isolamento & purificação , Filogenia , Inibidores de Proteassoma/farmacologia , Trichoderma/classificação , Trichoderma/genética , Trichoderma/isolamento & purificação
3.
J Nat Prod ; 83(1): 55-65, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31895573

RESUMO

A new method of screening was developed to generate 770 organic and water-soluble fractions from extracts of nine species of marine sponges, from the growth media of 18 species of marine-derived fungi, and from the growth media of 13 species of endophytic fungi. The screening results indicated that water-soluble fractions displayed significant bioactivity in cytotoxic, antibiotic, anti-Leishmania, anti-Trypanosoma cruzi, and inhibition of proteasome assays. Purification of water-soluble fractions from the growth medium of Penicillium solitum IS1-A provided the new glutamic acid derivatives solitumine A (1), solitumine B (2), and solitumidines A-D (3-6). The structures of compounds 1-6 have been established by analysis of spectroscopic data, chemical derivatizations, and vibrational circular dichroism calculations. Although no biological activity could be observed for compounds 1-6, the new structures reported for 1-6 indicate that the investigation of water-soluble natural products represents a relevant strategy in finding new secondary metabolites.


Assuntos
Glutamatos/química , Regiões Antárticas , Fungos/química , Estrutura Molecular , Penicillium/química , Água
4.
Braz. j. microbiol ; 49(4): 840-847, Oct.-Dec. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-974284

RESUMO

ABSTRACT Anthracnose is a crop disease usually caused by fungi in the genus Colletotrichum or Gloeosporium. These are considered one of the main pathogens, causing significant economic losses, such as in peppers and guarana. The current forms of control include the use of resistant cultivars, sanitary pruning and fungicides. However, even with the use of some methods of controlling these cultures, the crops are not free of anthracnose. Additionally, excessive application of fungicides increases the resistance of pathogens to agrochemicals and cause harm to human health and the environment. In order to find natural antifungal agents against guarana anthracnose, endophytic fungi were isolated from Amazon guarana. The compounds piliformic acid and cytochalasin D were isolated by chromatographic techniques from two Xylaria spp., guided by assays with Colletotrichum gloeosporioides. The isolated compounds were identified by spectrometric techniques, as NMR and mass spectrometry. This is the first report that piliformic acid and cytochalasin D have antifungal activity against C. gloeosporioides with MIC 2.92 and 2.46 µmol mL-1 respectively. Captan and difenoconazole were included as positive controls (MIC 16.63 and 0.02 µmol mL-1, respectively). Thus, Xylaria species presented a biotechnological potential and production of different active compounds which might be promising against anthracnose disease.


Assuntos
Doenças das Plantas/prevenção & controle , Xylariales/química , Paullinia/microbiologia , Endófitos/química , Fungicidas Industriais/farmacologia , Filogenia , Doenças das Plantas/microbiologia , Espectrometria de Massas , Xylariales/isolamento & purificação , Xylariales/genética , Xylariales/metabolismo , Estrutura Molecular , Colletotrichum/efeitos dos fármacos , Colletotrichum/fisiologia , Endófitos/isolamento & purificação , Endófitos/genética , Endófitos/metabolismo , Fungicidas Industriais/isolamento & purificação , Fungicidas Industriais/química
5.
Braz J Microbiol ; 49(4): 840-847, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29631892

RESUMO

Anthracnose is a crop disease usually caused by fungi in the genus Colletotrichum or Gloeosporium. These are considered one of the main pathogens, causing significant economic losses, such as in peppers and guarana. The current forms of control include the use of resistant cultivars, sanitary pruning and fungicides. However, even with the use of some methods of controlling these cultures, the crops are not free of anthracnose. Additionally, excessive application of fungicides increases the resistance of pathogens to agrochemicals and cause harm to human health and the environment. In order to find natural antifungal agents against guarana anthracnose, endophytic fungi were isolated from Amazon guarana. The compounds piliformic acid and cytochalasin D were isolated by chromatographic techniques from two Xylaria spp., guided by assays with Colletotrichum gloeosporioides. The isolated compounds were identified by spectrometric techniques, as NMR and mass spectrometry. This is the first report that piliformic acid and cytochalasin D have antifungal activity against C. gloeosporioides with MIC 2.92 and 2.46µmolmL-1 respectively. Captan and difenoconazole were included as positive controls (MIC 16.63 and 0.02µmolmL-1, respectively). Thus, Xylaria species presented a biotechnological potential and production of different active compounds which might be promising against anthracnose disease.


Assuntos
Endófitos/química , Fungicidas Industriais/farmacologia , Paullinia/microbiologia , Doenças das Plantas/prevenção & controle , Xylariales/química , Colletotrichum/efeitos dos fármacos , Colletotrichum/fisiologia , Endófitos/genética , Endófitos/isolamento & purificação , Endófitos/metabolismo , Fungicidas Industriais/química , Fungicidas Industriais/isolamento & purificação , Espectrometria de Massas , Estrutura Molecular , Filogenia , Doenças das Plantas/microbiologia , Xylariales/genética , Xylariales/isolamento & purificação , Xylariales/metabolismo
6.
Curr Microbiol ; 75(4): 441-449, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29159690

RESUMO

Tropical plants represent hotspots of endophytic fungal species diversity. Based on culture-dependent methods, we evaluated the endophytic fungal communities in leaves of three plant species found in the Brazilian Atlantic Rainforest: Begonia fischeri, Begonia olsoniae, and Begonia venosa. These species are found in two distant sites: a continental region and an insular area. A total of 426 fungal endophytes in 19 genera were isolated in pure culture including Colletotrichum (51.6% of isolates) and Diaporthe (22.5%) as the most abundant, followed by Phyllosticta (3.5%), Neopestalotiopsis (1.8%), Stagonospora (1.8%), and Nigrospora (1.6%) among the genera found in minor abundance. The diversity and composition of fungal taxa differed across plant hosts. Richness and diversity of fungi were higher in B. fischeri in comparison to B. olsoniae and B. venosa. Discriminatory analysis revealed that fungal communities are structured according to hosts, which means that each plant species had its distinct endophytic communities, but dominated by common fungal taxa. This is the first study to report fungal endophytes in begonia leaves and characterize their communities.


Assuntos
Begoniaceae/microbiologia , Endófitos/isolamento & purificação , Fungos/isolamento & purificação , Biodiversidade , Brasil , Endófitos/classificação , Endófitos/genética , Fungos/classificação , Fungos/genética , Filogenia , Floresta Úmida
7.
Org Lett ; 17(21): 5152-5, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26444492

RESUMO

The structure of the fungal metabolite roussoellatide (1) has been established by spectroscopic and X-ray diffraction analyses. Results from feeding experiments with [1-(13)C]acetate, [2-(13)C]acetate, and [1,2-(13)C]acetate were consistent with a biosynthetic pathway to the unprecedented skeleton of 1 involving Favorskii rearrangements in separate pentaketides, subsequently joined via an intermolecular Diels-Alder reaction.


Assuntos
Ascomicetos/química , Hidrocarbonetos Clorados/síntese química , Policetídeos/síntese química , Cristalografia por Raios X , Reação de Cicloadição , Hidrocarbonetos Clorados/química , Biologia Marinha , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Policetídeos/química
8.
Rev. bras. farmacogn ; 24(6): 651-659, Nov-Dec/2014. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: lil-741839

RESUMO

In the present investigation we report the antibacterial activity of halistanol sulfate A isolated from the sponge Petromica ciocalyptoides, as well as of rodriguesines A and B isolated from the ascidian Didemnum sp., against the caries etiologic agent Streptococcus mutans. The transcription levels of S. mutans virulence genes gtfB, gtfC and gbpB, as well as of housekeeping genes groEL and 16S, were evaluated by sqRT-PCR analysis of S. mutans planktonic cells. There were no alterations in the expression levels of groEL and 16S after antimicrobial treatment with halistanol sulfate A and with rodriguesines A and B, but the expression of the genes gtfB, gtfC and gbpB was down-regulated. Halistanol sulfate A displayed the most potent antimicrobial effect against S. mutans, with inhibition of biofilm formation and reduction of biofilm-associated gene expression in planktonic cells. Halistanol sulfate A also inhibited the initial oral bacteria colonizers, such as Streptococcus sanguinis, but at much higher concentrations. The results obtained indicate that halistanol sulfate A may be considered a potential scaffold for drug development in Streptococcus mutans antibiofilm therapy, the main etiologic agent of human dental caries. .

9.
Rev. bras. farmacogn ; 17(3): 287-318, jul.-set. 2007. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-465467

RESUMO

Herein we present the results of a screening with 349 crude extracts of Brazilian marine sponges, ascidians, bryozoans and octocorals, against 16 strains of susceptible and antibiotic-resistant bacteria, one yeast (Candida albicans), Mycobacterium tuberculosis H37Rv, three cancer cell lines MCF-7 (breast), B16 (murine melanoma ) and HCT8 (colon), and Leishmania tarentolae adenine phosphoribosyl transferase (L-APRT) enzyme. Less than 15 percent of marine sponge crude extracts displayed antibacterial activity, both against susceptible and antibiotic-resistant bacteria. Up to 40 percent of marine sponge crude extracts displayed antimycobacterial activity against M. tuberculosis H37Rv. Cytotoxicity was observed for 18 percent of marine sponge crude extracts. Finally, less than 3 percent of sponge extracts inhibited L-APRT. Less than 10 percent of ascidian crude extracts displayed antibacterial activity. More than 25 percent of ascidian crude extracts were active against M. tuberculosis and the three cancer cell lines. Only two crude extracts from the ascidian Polysyncraton sp. collected in different seasons (1995 and 1997) displayed activity against L-APRT. Less than 2 percent of bryozoan and octocoral crude extracts presented antibacterial activity, but a high percentage of crude extracts from bryozoan and octororal displayed cytotoxic (11 percent and 30 percent, respectively) and antimycobacterial (60 percent) activities. The extract of only one species of bryozoan, Bugula sp., presented inhibitory activity against L-APRT. Overall, the crude extracts of marine invertebrates herein investigated presented a high level of cytotoxic and antimycobacterial activities, a lower level of antibacterial activity and only a small number of crude extracts inhibited L-APRT. Taxonomic analysis of some of the more potently active crude extracts showed the occurrence of biological activity in taxa that have been previously chemically investigated. These...


No presente estudo apresentamos resultados da triagem biológica realizada com 349 extratos obtidos de esponjas marinhas, ascídias, briozoários e octocorais do Brasil, em testes contra 16 linhagens de bactérias comuns e resistentes à antibióticos, uma levedura (Candida albicans), Mycobacterium tuberculosis H37Rv, três linhagens de células tumorais MCF-7 (mama), B16 (melanoma murínico) e HCT8 (cólon), e de inibição da enzima adenina fosforribosil transferase de Leishmania tarentolae (L-APRT). Menos de 15 por cento dos extratos de esponja marinhas apresentaram atividade antibacteriana, contra linhagens resistentes ou não a antibióticos. Quase 40 por cento dos extratos de esponjas marinhas apresentaram atividade antimicobacteriana contra Mycobacterium tuberculosis H37Rv. Foi observada citotoxicidade para 18 por cento dos extratos de esponjas marinhas. Finalmente, menos de 3 por cento dos extratos de esponjas apresentaram atividade inibitória da enzima L-APRT. Menos de 10 por cento dos extratos de ascídias apresentaram atividade antibacteriana. Mais de 25 por cento dos extratos de ascídias apresentaram atividade contra M. tuberculosis e as três linhagens de células tumorais. Somente dois extratos obtidos da ascídia Polysyncraton sp. coletada em duas diferentes épocas (1995 e 1997) apresentaram atividade contra L-APRT. Menos de 2 por cento dos extratos de briozoários e octocorais apresentaram atividade antibacteriana, mas uma alta percentagem de extratos destes animais apresentaram atividades citotóxica (11 por cento e 30 por cento, respectivamente) e antimicobacteriana (60 por cento). O extrato de somente uma espécie de briozoário, Bugula sp., apresentou atividade inibitória da enzima L-APRT. A análise taxonômica de algumas espécies de invertebrados que forneceram alguns dos extratos mais ativos, indicou a ocorrência de atividade biológica em espécies pertencentes a grupos taxonômicos que já foram anteriormente investigados do ponto de vista...


Assuntos
Briozoários , Técnicas In Vitro , Inibidores Enzimáticos/farmacologia , Poríferos , Urocordados
10.
J Antibiot (Tokyo) ; 59(9): 553-63, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17136888

RESUMO

Chemical investigation of the cytotoxic and anti-tuberculosis active butanone extract obtained from the growth media of the marine-derived fungus Beauveria felina led to the isolation of two new destruxins, [beta-Me-Pro] destruxin E chlorohydrin (1) and pseudodestruxin C (3), along with five known cyclic depsipeptides. The structures of the new destruxin derivatives were established by analysis of spectroscopic data, while the absolute configuration of the common amino acid residues was established by Marfey's analysis. The absolute configuration of the 2(R),4(S)-5-chloro-2,4-dihydroxypentanoic acid residue in 1 could be established by application of a J-based configuration method followed by derivatization with R-MPA-Cl and NMR analysis.


Assuntos
Beauveria/química , Depsipeptídeos/química , Depsipeptídeos/isolamento & purificação , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Micotoxinas/isolamento & purificação , Aminoácidos/análise , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/isolamento & purificação , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antituberculose/química , Antibióticos Antituberculose/isolamento & purificação , Antibióticos Antituberculose/farmacologia , Linhagem Celular Tumoral , Depsipeptídeos/farmacologia , Proteínas Fúngicas/farmacologia , Humanos , Camundongos , Estrutura Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Micotoxinas/química , Análise Espectral
11.
J Org Chem ; 71(23): 8685-90, 2006 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-17080994

RESUMO

Three new disulfated meroterpenoids, ilhabelanol (1), ilhabrene (2), and isoakaterpin (3), have been isolated from extracts of the Brazilian marine sponge Callyspongia sp. Isoakaterpin (3) inhibits Leishmania spp. adenosine phosphoribosyl transferase with an IC50 of 1.05 microM. The structures of 1, 2, and 3 were elucidated by analysis of one- and two-dimensional NMR data. Ilhabelanol (1) and ilhabrene (2) both have unprecedented meroterpenoid carbon skeletons.


Assuntos
Adenina Fosforribosiltransferase/antagonistas & inibidores , Callyspongia/química , Inibidores Enzimáticos/química , Terpenos/química , Animais , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Leishmania/enzimologia , Conformação Molecular , Estereoisomerismo , Relação Estrutura-Atividade , Terpenos/isolamento & purificação , Terpenos/farmacologia
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