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1.
J Econ Entomol ; 109(2): 898-906, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26662735

RESUMO

Pentatomids (stink bugs) are major pests of soybean, Glycine max (L.) Merril. These pests reach high levels of infestation, cause severe damage to seeds by feeding, are linked to leaf retention, and are difficult to control. Host plant resistance is considered to be a valuable tool in integrated pest management and can assist in reducing the damage caused by stink bugs. This research evaluated the resistance of soybean genotypes in Brazil to the stink bug complex, the Neotropical brown stink bug, Euschistus heros (F.), redbanded stink bug, Piezodorus guildinii (Westwood), southern green stink bug, Nezara viridula (L.), green belly stink bug, Dichelops melacanthus (Dallas), and Edessa meditabunda (F.), by assessing infestation assay, yield reduction, seed damage, and leaf retention. Certain genotypes expressed different categories of resistance: least infested, low yield reduction, low levels of damage in seeds, and low levels of leaf retention. PI lines and IAC 78-2318 showed antixenotic resistance, and 'IAC 100' showed tolerance for the stink bug complex. This is the first study to evaluate several parameters of yield and seed quality using different soybean maturity groups under relatively high infestation by the three stink bugs species. The promising genotypes might be used in regions with a high incidence of stink bugs to manage their populations in combination with other integrated pest management practices.


Assuntos
Glycine max/genética , Herbivoria , Heterópteros , Animais , Genótipo
2.
Genet Mol Res ; 14(4): 13889-93, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26535704

RESUMO

Cavernicola pilosa is a triatomine species that lives in caves and feeds on bat blood. This vector has a wide geographical distribution, and is found in Brazil, Colombia, Panama, Peru, and Venezuela. Little is known about the reproductive biology of this species, because most previous studies have only characterized its morphology, morphometry, ecology, and epidemiology. Therefore, this study aimed to obtain preliminary data related to spermatogenesis in C. pilosa by conducting cytogenetic analysis. Analysis of the heterochromatic pattern of C. pilosa during the initial prophases revealed that heterochromatic blocks are only present in the sex chromosomes. Based on the analyses of the meiotic metaphase and prophases, we found that the sex determination system of C. pilosa is XY and the chromosomes are holocentric. C. pilosa spermatids are filamentous and have long flagella. It was not possible to detect corpuscle or filament heteropycnosis in spermatids of this species. The initial cytogenetic data presented in this study are important in characterizing the spermatogenesis and heterochromatic patterns of C. pilosa. Our results suggest that adaptation to troglodytism did not result in differences in spermatogenesis in this vector.


Assuntos
Análise Citogenética , Triatominae/genética , Animais , Heterocromatina , Metáfase , Poliploidia , Espermatogênese , Triatominae/crescimento & desenvolvimento
3.
Braz J Biol ; 83: e276493, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422255

RESUMO

This review article explores the potential of fermentations in the Amazon region as catalysts for economic and social development. It highlights the rich cultural and gastronomic diversity of the Amazon, focusing on indigenous fermented products. Two main products, tucupi and caxiri, are discussed in detail, emphasizing their significance in local cuisine and culture. The review examines the challenges and opportunities for industrial applications of these products, as well as their potential for social technology initiatives, particularly in the context of family farming. The sustainable production of native fermented products in the Amazon is seen as a means to preserve biodiversity, empower local communities, and promote cultural heritage. The article concludes that both industrial and social technologies have complementary roles in promoting economic growth, cultural preservation, and the well-being of the Amazon region, making it a promising hub for innovative and sustainable fermented food products on a global scale.


Assuntos
Biodiversidade , Tecnologia , Fermentação , Agricultura
4.
Braz J Biol ; 83: e275573, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126585

RESUMO

The emergence of bacterial resistance to antimicrobials poses a significant health threat. To address this issue, exploring the fungal diversity in freshwater environments in the Amazon Forest has potential in the search for new antimicrobials. This study aimed to investigate the production of antibacterial metabolites by aquatic fungi from Amazon lakes, specifically Lake Juá and Lake Maicá (Brazil-PA). The fungal isolates were obtained from wood fragments submerged in these lakes, and the ethyl acetate extracts were evaluated for antibacterial activity against Staphylococcus aureus ATCC 25923, S. aureus (MRSA), ATCC 43300, Escherichia coli ATCC 25922, and E. coli (ESBL) NCTC 13353. Additionally, toxicity of the extracts (EtOAc with antimicrobial activity) against human fibroblasts MRC-5 was investigated. The study identified 40 fungal strains with antimicrobial screening, and the ethyl acetate extracts of Fluviatispora C34, Helicascus C18, Monodictys C15, and Fusarium solani LM6281 exhibited antibacterial activity. F. solani LM6281 showed the lowest minimum inhibitory concentration (MIC) of 50 µg/mL against S. aureus strains and MIC of 100 µg/mL against E. coli strains including ESBL. The cytotoxicity (IC50) of the extract (EtOAc) of F. solani LM6281 was 34.5 µg/mL. Preliminary studies of the TLC culture and RNM-H from the extract (EtOAc) of F. solani suggested the presence of substances from the class of terpenes, quinones, phenolics, and flavonoids. This study highlights the potential of submerged wood fungi in the Amazon region to produce antibacterial substances, thus identifying them as sources of novel bioactive compounds with potential use in the pharmaceutical industry and regional bioeconomy.


Assuntos
Antibacterianos , Fungos , Madeira , Humanos , Antibacterianos/farmacologia , Brasil , Escherichia coli , Fungos/química , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Madeira/microbiologia
5.
J Fluoresc ; 22(4): 1151-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22488046

RESUMO

Cellular membranes have relevant roles in processes related to proteases like human kallikreins and cathepsins. As enzyme and substrate may interact with cell membranes and associated co-factors, it is important to take into account the behavior of peptide substrates in the lipid environment. In this paper we report an study based on energy transfer in two bradykinin derived peptides labeled with the donor-acceptor pair Abz/Eddnp (ortho-aminobenzoic acid/N-[2,4-dinitrophenyl]-ethylenediamine). Time-resolved fluorescence experiments were performed in phosphate buffer and in the presence of large unilamelar vesicles of phospholipids, and of micelles of sodium dodecyl sulphate (SDS). The decay kinetics were analyzed using the program CONTIN to obtain end-to-end distance distribution functions f(r). Despite of the large difference in the number of residues the end-to-end distance of the longer peptide (9 amino acid residues) is only 20 % larger than the values obtained for the shorter peptide (5 amino acid residues). The proline residue, in position 4 of the bradykinin sequence promotes a turn in the longer peptide chain, shortening its end-to-end distance. The surfactant SDS has a strong disorganizing effect, substantially broadening the distance distributions, while temperature increase has mild effects in the flexibility of the chains, causing small increase in the distribution width. The interaction with phospholipid vesicles stabilizes more compact conformations, decreasing end-to-end distances in the peptides. Anisotropy experiments showed that rotational diffusion was not severely affected by the interaction with the vesicles, suggesting a location for the peptides in the surface region of the bilayer, a result consistent with small effect of lipid phase transition on the peptides conformations.


Assuntos
Bradicinina/química , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Fosfolipídeos/metabolismo , Lipossomas Unilamelares/metabolismo , Sequência de Aminoácidos , Dimiristoilfosfatidilcolina/metabolismo , Cinética , Micelas , Fosfatidilgliceróis/metabolismo , Ligação Proteica , Espectrometria de Fluorescência , Água/química
6.
Braz J Biol ; 83: e242830, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34161455

RESUMO

Pesticide residues that contaminate the environment circulate within the hydrological cycle can accumulate within the food chain and cause problems to both environmental and human health. Microbes, however, are well known for their metabolic versatility and the ability to degrade chemically stable substances, including recalcitrant xenobiotics. The current study focused on bio-prospecting within Amazonian rainforest soils to find novel strains fungi capable of efficiently degrading the agriculturally and environmentally ubiquitous herbicide, glyphosate. Of 50 fungal strains isolated (using culture media supplemented with glyphosate as the sole carbon-substrate), the majority were Penicillium strains (60%) and the others were Aspergillus and Trichoderma strains (26 and 8%, respectively). All 50 fungal isolates could use glyphosate as a phosphorous source. Eight of these isolates grew better on glyphosate-supplemented media than on regular Czapek Dox medium. LC-MS revealed that glyphosate degradation by Penicillium 4A21 resulted in sarcosine and aminomethylphosphonic acid.


Assuntos
Herbicidas , Penicillium , Trichoderma , Aspergillus , Biodegradação Ambiental , Fungos , Glicina/análogos & derivados , Herbicidas/toxicidade , Humanos , Organofosfonatos , Solo , Microbiologia do Solo , Glifosato
7.
Braz J Biol ; 82: e241863, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133562

RESUMO

Since the classic studies of Alexander Flemming, Penicillium strains have been known as a rich source of antimicrobial substances. Recent studies have identified novel metabolites produced by Penicillium sclerotiorum that have antibacterial, antifouling and pharmaceutical activities. Here, we report the isolation of a P. sclerotiorum (LM 5679) from Amazonian soil and carry out a culture-based study to determine whether it can produce any novel secondary metabolite(s) that are not thus-far reported for this genus. Using a submerged culture system, secondary metabolites were recovered by solvent extract followed by thin-layer chromatography, nuclear magnetic resonance, and mass spectroscopy. One novel secondary metabolite was isolated from P. sclerotiorum (LM 5679); the phenolic compound 5-pentadecyl resorcinol widely known as an antifungal, that is produced by diverse plant species. This metabolite was not reported previously in any Penicillium species and was only found once before in fungi (that time, in a Fusarium). Here, we discuss the known activities of 5-pentadecyl resorcinol in the context of its mode-of-action as a hydrophobic (chaotropicity-mediated) stressor.


Assuntos
Penicillium , Antibacterianos , Antifúngicos , Resorcinóis
8.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469026

RESUMO

Abstract Pesticide residues that contaminate the environment circulate within the hydrological cycle can accumulate within the food chain and cause problems to both environmental and human health. Microbes, however, are well known for their metabolic versatility and the ability to degrade chemically stable substances, including recalcitrant xenobiotics. The current study focused on bio-prospecting within Amazonian rainforest soils to find novel strains fungi capable of efficiently degrading the agriculturally and environmentally ubiquitous herbicide, glyphosate. Of 50 fungal strains isolated (using culture media supplemented with glyphosate as the sole carbon-substrate), the majority were Penicillium strains (60%) and the others were Aspergillus and Trichoderma strains (26 and 8%, respectively). All 50 fungal isolates could use glyphosate as a phosphorous source. Eight of these isolates grew better on glyphosate-supplemented media than on regular Czapek Dox medium. LC-MS revealed that glyphosate degradation by Penicillium 4A21 resulted in sarcosine and aminomethylphosphonic acid.


Resumo Resíduos de agrotóxicos que contaminam o meio ambiente circulam no ciclo hidrológico, podendo se acumular na cadeia alimentar e causar problemas tanto à saúde ambiental quanto humana. Por sua vez, microrganismos são bem conhecidos por sua versatilidade metabólica e capacidade de degradar substâncias quimicamente estáveis, incluindo xenobióticos recalcitrantes. O estudo atual se concentrou na bioprospecção nos solos da floresta amazônica para encontrar novas linhagens de fungos capazes de degradar com eficiência o herbicida onipresente na agricultura e no meio ambiente, o glifosato. Entre os 50 fungos isolados (usando meio de cultura suplementado com glifosato como única fonte de carbono), a maioria eram isolados do gênero Penicillium (60%) e os outros eram isolados de Aspergillus e Trichoderma (26 e 8%, respectivamente). Todos os 50 isolados de fungos foram capazes de usar glifosato como fonte de fósforo. Oito desses isolados cresceram melhor em meio suplementado com glifosato do que em meio Czapek Dox regular. LC-MS revelou que a degradação do glifosato por Penicillium 4A21 resultou nos metabólitos sarcosina e ácido aminometilfosfônico.

9.
Braz. j. biol ; 83: e242830, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278540

RESUMO

Abstract Pesticide residues that contaminate the environment circulate within the hydrological cycle can accumulate within the food chain and cause problems to both environmental and human health. Microbes, however, are well known for their metabolic versatility and the ability to degrade chemically stable substances, including recalcitrant xenobiotics. The current study focused on bio-prospecting within Amazonian rainforest soils to find novel strains fungi capable of efficiently degrading the agriculturally and environmentally ubiquitous herbicide, glyphosate. Of 50 fungal strains isolated (using culture media supplemented with glyphosate as the sole carbon-substrate), the majority were Penicillium strains (60%) and the others were Aspergillus and Trichoderma strains (26 and 8%, respectively). All 50 fungal isolates could use glyphosate as a phosphorous source. Eight of these isolates grew better on glyphosate-supplemented media than on regular Czapek Dox medium. LC-MS revealed that glyphosate degradation by Penicillium 4A21 resulted in sarcosine and aminomethylphosphonic acid.


Resumo Resíduos de agrotóxicos que contaminam o meio ambiente circulam no ciclo hidrológico, podendo se acumular na cadeia alimentar e causar problemas tanto à saúde ambiental quanto humana. Por sua vez, microrganismos são bem conhecidos por sua versatilidade metabólica e capacidade de degradar substâncias quimicamente estáveis, incluindo xenobióticos recalcitrantes. O estudo atual se concentrou na bioprospecção nos solos da floresta amazônica para encontrar novas linhagens de fungos capazes de degradar com eficiência o herbicida onipresente na agricultura e no meio ambiente, o glifosato. Entre os 50 fungos isolados (usando meio de cultura suplementado com glifosato como única fonte de carbono), a maioria eram isolados do gênero Penicillium (60%) e os outros eram isolados de Aspergillus e Trichoderma (26 e 8%, respectivamente). Todos os 50 isolados de fungos foram capazes de usar glifosato como fonte de fósforo. Oito desses isolados cresceram melhor em meio suplementado com glifosato do que em meio Czapek Dox regular. LC-MS revelou que a degradação do glifosato por Penicillium 4A21 resultou nos metabólitos sarcosina e ácido aminometilfosfônico.


Assuntos
Humanos , Penicillium , Trichoderma , Herbicidas/toxicidade , Aspergillus , Solo , Microbiologia do Solo , Biodegradação Ambiental , Organofosfonatos , Fungos , Glicina/análogos & derivados
10.
Braz. j. biol ; 83: 1-7, 2023. graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468810

RESUMO

Pesticide residues that contaminate the environment circulate within the hydrological cycle can accumulate within the food chain and cause problems to both environmental and human health. Microbes, however, are well known for their metabolic versatility and the ability to degrade chemically stable substances, including recalcitrant xenobiotics. The current study focused on bio-prospecting within Amazonian rainforest soils to find novel strains fungi capable of efficiently degrading the agriculturally and environmentally ubiquitous herbicide, glyphosate. Of 50 fungal strains isolated (using culture media supplemented with glyphosate as the sole carbon-substrate), the majority were Penicillium strains (60%) and the others were Aspergillus and Trichoderma strains (26 and 8%, respectively). All 50 fungal isolates could use glyphosate as a phosphorous source. Eight of these isolates grew better on glyphosate-supplemented media than on regular Czapek Dox medium. LC-MS revealed that glyphosate degradation by Penicillium 4A21 resulted in sarcosine and aminomethylphosphonic acid.


Resíduos de agrotóxicos que contaminam o meio ambiente circulam no ciclo hidrológico, podendo se acumular na cadeia alimentar e causar problemas tanto à saúde ambiental quanto humana. Por sua vez, microrganismos são bem conhecidos por sua versatilidade metabólica e capacidade de degradar substâncias quimicamente estáveis, incluindo xenobióticos recalcitrantes. O estudo atual se concentrou na bioprospecção nos solos da floresta amazônica para encontrar novas linhagens de fungos capazes de degradar com eficiência o herbicida onipresente na agricultura e no meio ambiente, o glifosato. Entre os 50 fungos isolados (usando meio de cultura suplementado com glifosato como única fonte de carbono), a maioria eram isolados do gênero Penicillium (60%) e os outros eram isolados de Aspergillus e Trichoderma (26 e 8%, respectivamente). Todos os 50 isolados de fungos foram capazes de usar glifosato como fonte de fósforo. Oito desses isolados cresceram melhor em meio suplementado com glifosato do que em meio Czapek Dox regular. LC-MS revelou que a degradação do glifosato por Penicillium 4A21 resultou nos metabólitos sarcosina e ácido aminometilfosfônico.


Assuntos
Animais , Aspergillus , Herbicidas/toxicidade , Microbiologia do Solo , Penicillium , Trichoderma
11.
Braz. J. Biol. ; 83: 1-7, 2023. graf, tab
Artigo em Inglês | VETINDEX | ID: vti-765387

RESUMO

Pesticide residues that contaminate the environment circulate within the hydrological cycle can accumulate within the food chain and cause problems to both environmental and human health. Microbes, however, are well known for their metabolic versatility and the ability to degrade chemically stable substances, including recalcitrant xenobiotics. The current study focused on bio-prospecting within Amazonian rainforest soils to find novel strains fungi capable of efficiently degrading the agriculturally and environmentally ubiquitous herbicide, glyphosate. Of 50 fungal strains isolated (using culture media supplemented with glyphosate as the sole carbon-substrate), the majority were Penicillium strains (60%) and the others were Aspergillus and Trichoderma strains (26 and 8%, respectively). All 50 fungal isolates could use glyphosate as a phosphorous source. Eight of these isolates grew better on glyphosate-supplemented media than on regular Czapek Dox medium. LC-MS revealed that glyphosate degradation by Penicillium 4A21 resulted in sarcosine and aminomethylphosphonic acid.(AU)


Resíduos de agrotóxicos que contaminam o meio ambiente circulam no ciclo hidrológico, podendo se acumular na cadeia alimentar e causar problemas tanto à saúde ambiental quanto humana. Por sua vez, microrganismos são bem conhecidos por sua versatilidade metabólica e capacidade de degradar substâncias quimicamente estáveis, incluindo xenobióticos recalcitrantes. O estudo atual se concentrou na bioprospecção nos solos da floresta amazônica para encontrar novas linhagens de fungos capazes de degradar com eficiência o herbicida onipresente na agricultura e no meio ambiente, o glifosato. Entre os 50 fungos isolados (usando meio de cultura suplementado com glifosato como única fonte de carbono), a maioria eram isolados do gênero Penicillium (60%) e os outros eram isolados de Aspergillus e Trichoderma (26 e 8%, respectivamente). Todos os 50 isolados de fungos foram capazes de usar glifosato como fonte de fósforo. Oito desses isolados cresceram melhor em meio suplementado com glifosato do que em meio Czapek Dox regular. LC-MS revelou que a degradação do glifosato por Penicillium 4A21 resultou nos metabólitos sarcosina e ácido aminometilfosfônico.(AU)


Assuntos
Animais , Microbiologia do Solo , Aspergillus , Penicillium , Trichoderma , Herbicidas/toxicidade
12.
Braz. j. biol ; 82: 1-9, 2022. ilus, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468536

RESUMO

Since the classic studies of Alexander Flemming, Penicillium strains have been known as a rich source of antimicrobial substances. Recent studies have identified novel metabolites produced by Penicillium sclerotiorum that have antibacterial, antifouling and pharmaceutical activities. Here, we report the isolation of a P. sclerotiorum (LM 5679) from Amazonian soil and carry out a culture-based study to determine whether it can produce any novel secondary metabolite(s) that are not thus-far reported for this genus. Using a submerged culture system, secondary metabolites were recovered by solvent extract followed by thin-layer chromatography, nuclear magnetic resonance, and mass spectroscopy. One novel secondary metabolite was isolated from P. sclerotiorum (LM 5679); the phenolic compound 5-pentadecyl resorcinol widely known as an antifungal, that is produced by diverse plant species. This metabolite was not reported previously in any Penicillium species and was only found once before in fungi (that time, in a Fusarium). Here, we discuss the known activities of 5-pentadecyl resorcinol in the context of its mode-of-action as a hydrophobic (chaotropicity-mediated) stressor.


Desde os estudos clássicos de Alexander Flemming, as cepas de Penicillium são conhecidas como uma fonte rica em substâncias antimicrobianas. Estudos recentes identificaram novos metabólitos produzidos pela espécie Penicillium sclerotiorum com atividades antibacteriana, anti-incrustante e farmacêutica. Aqui, relatamos o isolamento de uma colônia de P. sclerotiorum (LM 5679) do solo amazônico e relatamos também o estudo baseado em cultura para determinar se ele pode produzir qualquer novo metabólito (s) secundário (s) que não foram relatados até agora para este gênero. Usando um sistema de cultura submerso, os metabólitos secundários foram recuperados por extrato de solvente seguido por cromatografia em camada delgada, ressonância magnética nuclear e espectroscopia de massa. Um novo metabólito secundário foi isolado de P. sclerotiorum (LM 5679); o composto fenólico 5-pentadecil resorcinol que é amplamente conhecido como um antifúngico que é produzido por diversas espécies de plantas. Este metabólito não foi relatado anteriormente em nenhuma espécie de Penicillium, e foi encontrado apenas uma vez em fungos (Fusarium). Aqui, discutimos as atividades conhecidas do 5-pentadecil resorcinol no contexto de seu modo de ação como um estressor hidrofóbico (mediado pela caotropicidade).


Assuntos
Antifúngicos/isolamento & purificação , Compostos Fenólicos/análise , Penicillium/química , Fusarium
13.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468723

RESUMO

Abstract Since the classic studies of Alexander Flemming, Penicillium strains have been known as a rich source of antimicrobial substances. Recent studies have identified novel metabolites produced by Penicillium sclerotiorum that have antibacterial, antifouling and pharmaceutical activities. Here, we report the isolation of a P. sclerotiorum (LM 5679) from Amazonian soil and carry out a culture-based study to determine whether it can produce any novel secondary metabolite(s) that are not thus-far reported for this genus. Using a submerged culture system, secondary metabolites were recovered by solvent extract followed by thin-layer chromatography, nuclear magnetic resonance, and mass spectroscopy. One novel secondary metabolite was isolated from P. sclerotiorum (LM 5679); the phenolic compound 5-pentadecyl resorcinol widely known as an antifungal, that is produced by diverse plant species. This metabolite was not reported previously in any Penicillium species and was only found once before in fungi (that time, in a Fusarium). Here, we discuss the known activities of 5-pentadecyl resorcinol in the context of its mode-of-action as a hydrophobic (chaotropicity-mediated) stressor.


Resumo Desde os estudos clássicos de Alexander Flemming, as cepas de Penicillium são conhecidas como uma fonte rica em substâncias antimicrobianas. Estudos recentes identificaram novos metabólitos produzidos pela espécie Penicillium sclerotiorum com atividades antibacteriana, anti-incrustante e farmacêutica. Aqui, relatamos o isolamento de uma colônia de P. sclerotiorum (LM 5679) do solo amazônico e relatamos também o estudo baseado em cultura para determinar se ele pode produzir qualquer novo metabólito (s) secundário (s) que não foram relatados até agora para este gênero. Usando um sistema de cultura submerso, os metabólitos secundários foram recuperados por extrato de solvente seguido por cromatografia em camada delgada, ressonância magnética nuclear e espectroscopia de massa. Um novo metabólito secundário foi isolado de P. sclerotiorum (LM 5679); o composto fenólico 5-pentadecil resorcinol que é amplamente conhecido como um antifúngico que é produzido por diversas espécies de plantas. Este metabólito não foi relatado anteriormente em nenhuma espécie de Penicillium, e foi encontrado apenas uma vez em fungos (Fusarium). Aqui, discutimos as atividades conhecidas do 5-pentadecil resorcinol no contexto de seu modo de ação como um estressor hidrofóbico (mediado pela caotropicidade).

14.
Braz. j. biol ; 82: e241863, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278488

RESUMO

Since the classic studies of Alexander Flemming, Penicillium strains have been known as a rich source of antimicrobial substances. Recent studies have identified novel metabolites produced by Penicillium sclerotiorum that have antibacterial, antifouling and pharmaceutical activities. Here, we report the isolation of a P. sclerotiorum (LM 5679) from Amazonian soil and carry out a culture-based study to determine whether it can produce any novel secondary metabolite(s) that are not thus-far reported for this genus. Using a submerged culture system, secondary metabolites were recovered by solvent extract followed by thin-layer chromatography, nuclear magnetic resonance, and mass spectroscopy. One novel secondary metabolite was isolated from P. sclerotiorum (LM 5679); the phenolic compound 5-pentadecyl resorcinol widely known as an antifungal, that is produced by diverse plant species. This metabolite was not reported previously in any Penicillium species and was only found once before in fungi (that time, in a Fusarium). Here, we discuss the known activities of 5-pentadecyl resorcinol in the context of its mode-of-action as a hydrophobic (chaotropicity-mediated) stressor.


Desde os estudos clássicos de Alexander Flemming, as cepas de Penicillium são conhecidas como uma fonte rica em substâncias antimicrobianas. Estudos recentes identificaram novos metabólitos produzidos pela espécie Penicillium sclerotiorum com atividades antibacteriana, anti-incrustante e farmacêutica. Aqui, relatamos o isolamento de uma colônia de P. sclerotiorum (LM 5679) do solo amazônico e relatamos também o estudo baseado em cultura para determinar se ele pode produzir qualquer novo metabólito (s) secundário (s) que não foram relatados até agora para este gênero. Usando um sistema de cultura submerso, os metabólitos secundários foram recuperados por extrato de solvente seguido por cromatografia em camada delgada, ressonância magnética nuclear e espectroscopia de massa. Um novo metabólito secundário foi isolado de P. sclerotiorum (LM 5679); o composto fenólico 5-pentadecil resorcinol que é amplamente conhecido como um antifúngico que é produzido por diversas espécies de plantas. Este metabólito não foi relatado anteriormente em nenhuma espécie de Penicillium, e foi encontrado apenas uma vez em fungos (Fusarium). Aqui, discutimos as atividades conhecidas do 5-pentadecil resorcinol no contexto de seu modo de ação como um estressor hidrofóbico (mediado pela caotropicidade).


Assuntos
Penicillium , Resorcinóis , Antibacterianos , Antifúngicos
15.
Braz. J. Biol. ; 82: 1-9, 2022. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-33406

RESUMO

Since the classic studies of Alexander Flemming, Penicillium strains have been known as a rich source of antimicrobial substances. Recent studies have identified novel metabolites produced by Penicillium sclerotiorum that have antibacterial, antifouling and pharmaceutical activities. Here, we report the isolation of a P. sclerotiorum (LM 5679) from Amazonian soil and carry out a culture-based study to determine whether it can produce any novel secondary metabolite(s) that are not thus-far reported for this genus. Using a submerged culture system, secondary metabolites were recovered by solvent extract followed by thin-layer chromatography, nuclear magnetic resonance, and mass spectroscopy. One novel secondary metabolite was isolated from P. sclerotiorum (LM 5679); the phenolic compound 5-pentadecyl resorcinol widely known as an antifungal, that is produced by diverse plant species. This metabolite was not reported previously in any Penicillium species and was only found once before in fungi (that time, in a Fusarium). Here, we discuss the known activities of 5-pentadecyl resorcinol in the context of its mode-of-action as a hydrophobic (chaotropicity-mediated) stressor.(AU)


Desde os estudos clássicos de Alexander Flemming, as cepas de Penicillium são conhecidas como uma fonte rica em substâncias antimicrobianas. Estudos recentes identificaram novos metabólitos produzidos pela espécie Penicillium sclerotiorum com atividades antibacteriana, anti-incrustante e farmacêutica. Aqui, relatamos o isolamento de uma colônia de P. sclerotiorum (LM 5679) do solo amazônico e relatamos também o estudo baseado em cultura para determinar se ele pode produzir qualquer novo metabólito (s) secundário (s) que não foram relatados até agora para este gênero. Usando um sistema de cultura submerso, os metabólitos secundários foram recuperados por extrato de solvente seguido por cromatografia em camada delgada, ressonância magnética nuclear e espectroscopia de massa. Um novo metabólito secundário foi isolado de P. sclerotiorum (LM 5679); o composto fenólico 5-pentadecil resorcinol que é amplamente conhecido como um antifúngico que é produzido por diversas espécies de plantas. Este metabólito não foi relatado anteriormente em nenhuma espécie de Penicillium, e foi encontrado apenas uma vez em fungos (Fusarium). Aqui, discutimos as atividades conhecidas do 5-pentadecil resorcinol no contexto de seu modo de ação como um estressor hidrofóbico (mediado pela caotropicidade).(AU)


Assuntos
Penicillium/química , Antifúngicos/isolamento & purificação , Compostos Fenólicos/análise , Fusarium
16.
Ars vet ; 37(1): 05-09, 2021.
Artigo em Português | VETINDEX | ID: biblio-1463570

RESUMO

O tratamento do leite em ultra alta temperatura (UAT) possibilita a eliminação de patógenos e aumento do tempo de prateleira, no entanto, bactérias psicrotróficas são associadas a efeitos negativos no produto, como lipólise, rancificação e a geleificação. Resultado da resistência de alguns esporos ao processamento, e à possível atividade residual de enzimas termorresistentes. Assim, o objetivo deste estudo foi enumerar bactérias psicrotróficas e realizar a prova de lactofermentação em leites UAT comercializados na região de Curitiba, Paraná. Foram adquiridas 60 amostras de duas marcas (30 da marca A e 30 da marca B) quinzenalmente em três diferentes momentos. Em cada momento 10 amostras de um mesmo lote eram separadas em dois grupos (D0 e D7), sendo D0: cinco amostras avaliadas no dia da compra, e D7: cinco amostras avaliadas após incubação a 37± 1ºC/7 dias e analisadas quanto à enumeração de bactérias psicrotróficas, coloração de Gram e prova da lactofermentação. Em D0, uma (3,4%) amostra (marca A) apresentou crescimento de psicrotróficos (2,50 x 105 UFC/mL), Gram negativos. As amostras da marca B não apresentaram crescimento microbiano. Vinte e cinco (83,3%) amostras não formaram coágulo, e cinco (16,7%) produziram coágulo esponjoso. Em D7, nenhuma amostra apresentou contagem bacteriana, 20 (66,7%) não produziram coágulo e 10 (33,3%) produziram coágulo esponjoso. O processo UAT utilizado pela marca A não garantiu efetividade na redução de bactérias psicrotróficas, e o resultado do teste de lactofermentação indica a possível contaminação por coliformes em ambas as marcas. Ainda, a ausência de coágulos em diversas amostras pode ser um indicativo do uso de conservantes, o que é considerado fraude.


The beneficial effects of ultra-pasteurization milk treatment include elimination of milk pathogens, besides increasing the product's shelf-life, however, psychrotrophic bacteria are associated with several negative effects in the final product such as lipolysis, rancidification and gelation. This results from heat-resistant spores and its possible residual extracellular heat-resistant enzymes activity. With that in mind, this paper aimed to quantify psychrotrophic bacteria and perform a milk clotting test in UHT milk sold in Curitiba, Paraná. 60 samples from two brands were acquired (30 from A brand and 30 from B brand) each 15 days in different moments. Each time, 10 samples from a same batch were separated in two groups (D0 and D7), being D0: five samples analyzed in the purchase day, and D7: five samples analyzed after incubation at 37± 1ºC/7 days and evaluated regarding enumeration of psychrotrophic bacteria, Gram staining and milk clotting test. The heat-treating process effectiveness was evaluated by analyzing 30 samples from each brand, A and B, totalizing 60, being 10 from each different production batches, through the surface inoculation method in PCA, milk clotting test and classification of the isolated colonies by the Gram method. In D0, one (3,4%) sample (from A brand) resulted in Gram negative psychrotrophic growing (2,50 x 105 UFC/mL) . Samples from B brand did not result in bacterial growth. 25 samples (83,3%) did not clot, and five (16,7%) produced sponge clots. In D7, none of the samples presented bacterial growth, 20 (66,7%) did not clot and 10 (33,3%) produced sponge clots. Mesophilic bacterial culture was not done. The A brand UHT process did not grant sterilization regarding psychrotrophic bacteria, and the milk clotting results indicate possible coliforms contamination in both brands. Furthermore, clot absence in several samples could indicate preservatives usage, which is considered fraud.


Assuntos
Leite/fisiologia , Leite/química , Temperatura Alta , Técnicas Microbiológicas
17.
Ars Vet. ; 37(1): 05-09, 2021.
Artigo em Português | VETINDEX | ID: vti-30669

RESUMO

O tratamento do leite em ultra alta temperatura (UAT) possibilita a eliminação de patógenos e aumento do tempo de prateleira, no entanto, bactérias psicrotróficas são associadas a efeitos negativos no produto, como lipólise, rancificação e a geleificação. Resultado da resistência de alguns esporos ao processamento, e à possível atividade residual de enzimas termorresistentes. Assim, o objetivo deste estudo foi enumerar bactérias psicrotróficas e realizar a prova de lactofermentação em leites UAT comercializados na região de Curitiba, Paraná. Foram adquiridas 60 amostras de duas marcas (30 da marca A e 30 da marca B) quinzenalmente em três diferentes momentos. Em cada momento 10 amostras de um mesmo lote eram separadas em dois grupos (D0 e D7), sendo D0: cinco amostras avaliadas no dia da compra, e D7: cinco amostras avaliadas após incubação a 37± 1ºC/7 dias e analisadas quanto à enumeração de bactérias psicrotróficas, coloração de Gram e prova da lactofermentação. Em D0, uma (3,4%) amostra (marca A) apresentou crescimento de psicrotróficos (2,50 x 105 UFC/mL), Gram negativos. As amostras da marca B não apresentaram crescimento microbiano. Vinte e cinco (83,3%) amostras não formaram coágulo, e cinco (16,7%) produziram coágulo esponjoso. Em D7, nenhuma amostra apresentou contagem bacteriana, 20 (66,7%) não produziram coágulo e 10 (33,3%) produziram coágulo esponjoso. O processo UAT utilizado pela marca A não garantiu efetividade na redução de bactérias psicrotróficas, e o resultado do teste de lactofermentação indica a possível contaminação por coliformes em ambas as marcas. Ainda, a ausência de coágulos em diversas amostras pode ser um indicativo do uso de conservantes, o que é considerado fraude.(AU)


The beneficial effects of ultra-pasteurization milk treatment include elimination of milk pathogens, besides increasing the product's shelf-life, however, psychrotrophic bacteria are associated with several negative effects in the final product such as lipolysis, rancidification and gelation. This results from heat-resistant spores and its possible residual extracellular heat-resistant enzymes activity. With that in mind, this paper aimed to quantify psychrotrophic bacteria and perform a milk clotting test in UHT milk sold in Curitiba, Paraná. 60 samples from two brands were acquired (30 from A brand and 30 from B brand) each 15 days in different moments. Each time, 10 samples from a same batch were separated in two groups (D0 and D7), being D0: five samples analyzed in the purchase day, and D7: five samples analyzed after incubation at 37± 1ºC/7 days and evaluated regarding enumeration of psychrotrophic bacteria, Gram staining and milk clotting test. The heat-treating process effectiveness was evaluated by analyzing 30 samples from each brand, A and B, totalizing 60, being 10 from each different production batches, through the surface inoculation method in PCA, milk clotting test and classification of the isolated colonies by the Gram method. In D0, one (3,4%) sample (from A brand) resulted in Gram negative psychrotrophic growing (2,50 x 105 UFC/mL) . Samples from B brand did not result in bacterial growth. 25 samples (83,3%) did not clot, and five (16,7%) produced sponge clots. In D7, none of the samples presented bacterial growth, 20 (66,7%) did not clot and 10 (33,3%) produced sponge clots. Mesophilic bacterial culture was not done. The A brand UHT process did not grant sterilization regarding psychrotrophic bacteria, and the milk clotting results indicate possible coliforms contamination in both brands. Furthermore, clot absence in several samples could indicate preservatives usage, which is considered fraud.(AU)


Assuntos
Leite/química , Leite/fisiologia , Temperatura Alta , Técnicas Microbiológicas , Técnicas Microbiológicas
19.
Biochim Biophys Acta ; 1474(2): 251-61, 2000 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-10742606

RESUMO

Förster resonance energy transfer (FRET) was used to study the conformational dynamics of bradykinin related peptides. The fluorescent probe aminobenzoic acid (Abz) bound to the amino terminal of bradykinin maintained its fluorescence characteristics, like high quantum yield and excited state decay dominated by a lifetime of 8.3 ns. The binding of the acceptor group N-[2, 4-dinitrophenyl]-ethylenediamine (EDDnp) to the carboxy terminal of Abz labeled bradykinin resulted in a drastic decrease of the fluorescence intensity and in a fastening of the excited state decay. The change of the decay kinetics to an heterogeneous process, precludes the use of energy transfer models based on a single fixed distance between donor and acceptor. The computational package CONTIN was employed to the analysis of time-resolved fluorescence data, allowing the recovery of a distance distribution between donor and acceptor corresponding to the end-to-end distance of the labeled peptide. The distance distribution reflects the occurrence of distinct conformations for the peptide, that coexist in equilibrium during the fluorescence lifetime. We observed three distance populations for bradykinin in water, that merged to two populations when the solvent was trifluoroethanol (TFE). The results were consistent with those obtained from circular dichroism spectroscopy, that showed structural flexibility in water and the presence of more defined secondary structure in TFE. We also studied several peptides related to bradykinin, and the results emphasized the formation of turns involving the proline residues and the decrease of conformational flexibility induced by using TFE as the solvent.


Assuntos
Bradicinina/química , Sequência de Aminoácidos , Dicroísmo Circular , Transferência de Energia , Polarização de Fluorescência , Corantes Fluorescentes
20.
Arq Neuropsiquiatr ; 44(4): 383-90, 1986 Dec.
Artigo em Português | MEDLINE | ID: mdl-3606431

RESUMO

The authors report a case of right midbrain and high pons haemorrhage with complete external ophthalmoplegia, except bilateral convergence, voluntary and automatic-reflex abduction of the left eye and adduction of this eye with vestibulo-ocular reflex ("one-and-a-half syndrome"). There is voluntary-automatic dissociation of the eyelids motricity and the vertical gaze. Still, there is sensitive-motor hemiplegia at left and asterixis.


Assuntos
Hemorragia Cerebral/complicações , Mesencéfalo/irrigação sanguínea , Oftalmoplegia/etiologia , Ponte/irrigação sanguínea , Hemorragia Cerebral/diagnóstico por imagem , Movimentos Oculares , Feminino , Humanos , Pessoa de Meia-Idade , Oftalmoplegia/fisiopatologia , Reflexo Vestíbulo-Ocular , Tomografia Computadorizada por Raios X
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