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1.
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
2.
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
3.
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).

4.
Malaysian Journal of Microbiology ; : 245-252, 2020.
Artigo em Inglês | WPRIM | ID: wpr-964129

RESUMO

Aims@#Biocontrol of fungal plant pathogens using beneficial microorganisms is a safer alternative over synthetic fungicides. PHP12 is a bacterial strain isolated from healthy oil palm rhizosphere and is closely related to the recently described Burkholderia stagnalis, a member of the Burkholderia cepacia complex. This study aimed to characterize the antifungal activity spectrum of PHP12 and identify the antifungal compounds produced by the strain.@*Methodology and results@#The antifungal activity of PHP12 was characterized by growing fungal strains in the presence and absence of PHP12 and measuring the radius of the antifungal zone. PHP12 inhibited the growth of fungal pathogens including Ganoderma boninense, Curvularia oryzae, Phellinus noxius and Colletotrichum capsici. However, PHP12 did not inhibit the growth of Trichoderma asperellum, a known fungal biocontrol agent. The antifungal compounds of PHP12 were precipitated using ammonium sulfate and further purified with HPLC followed by identification using Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometric (LC/ESI-MS). The LC/ESI-MS analysis showed the presence of an oligopeptide with a molecular weight of 1210.63 Da. The peptide consists of heavily modified amino acids that are linked by a hexose residue. @*Conclusion, significance and impact of study@#Although characteristics of the antifungal compounds are similar to other antifungal peptides from Burkholderia such as occidiofungin, there have been no reports of antifungal peptides from B. stagnalis with the corresponding molecular weight or fragmentation profile. The novelty of the compound, as well as its antifungal spectrum, makes PHP12 an interesting strain to be investigated further as a biocontrol agent.


Assuntos
Fungicidas Industriais
5.
J. venom. anim. toxins incl. trop. dis ; 26: e20200023, 2020. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1135136

RESUMO

Endemic systemic mycoses remain a health challenge, since these opportunistic diseases are increasingly infecting immunosuppressed patients. The simultaneous use of antifungal compounds and other drugs to treat infectious or non-infectious diseases has led to several interactions and undesirable effects. Thus, new antifungal compounds should be investigated. The present study aimed to evaluate the activity of liriodenine extracted from Annona macroprophyllata on agents of systemic mycoses, with emphasis on the genus Paracoccidioides. Methods: The minimum inhibitory concentration (MIC) and minimum fungicide concentration (MFC) were determined by the microdilution method. The cellular alterations caused by liriodenine on a standard P. brasiliensis (Pb18) strain were evaluated by transmission and scanning electron microscopy. Results: Liriodenine was effective only in 3 of the 8 strains of the genus Paracoccidioides and in the Histoplasma capsulatum strain, in a very low concentration (MIC of 1.95 µg.mL-1); on yeasts of Candida spp. (MIC of 125 to 250 µg.mL-1), including C. krusei (250 µg.mL-1), which has intrinsic resistance to fluconazole; and in Cryptococcus neoformans and Cryptococcus gattii (MIC of 62.5 µg.mL-1). However, liriodenine was not effective against Aspergillus fumigatus at the studied concentrations. Liriodenine exhibited fungicidal activity against all standard strains and clinical isolates that showed to be susceptible by in vitro tests. Electron microscopy revealed cytoplasmic alterations and damage to the cell wall of P. brasiliensis (Pb18). Conclusion: Our results indicate that liriodenine is a promising fungicidal compound that should undergo further investigation with some chemical modifications.(AU)


Assuntos
Paracoccidioides , Microscopia Eletrônica , Testes de Sensibilidade Microbiana , Cryptococcus neoformans , Cryptococcus gattii , Micoses , Antifúngicos/isolamento & purificação
6.
Asian Pacific Journal of Tropical Medicine ; (12): 123-129, 2019.
Artigo em Inglês | WPRIM | ID: wpr-846890

RESUMO

Objective: To isolate and identify the antifungal compounds from Curcuma amada. Methods: The antifungal activity was measured by the diameter of colonies grown on Petri dish, microscopic observation, and CLSI microdilution methods. The antifungal compounds were isolated through bioactivity guided purification by using silica gel and high-performance liquid chromatography. Structural identification of the antifungal compounds was conducted using 1H NMR, 13C NMR, and liquid chromatography-tandem mass spectrometry. Results: The purified antifungal compounds were zederone and furanodienone. These two compounds showed dose-dependent antifungal activity against Fusarium solani sensu lato. The concentration required for 50% growth inhibition (IC50) of FSSL ranged from 115 to 129 μM and 82 to 91 μM for zederone and furanodienone, respectively. Conclusion: This study suggested that the isolated compounds from Curcuma amada could be promising natural antifungal agents to control the diseases caused by Fusarium solani sensu lato.

7.
Asian Pacific Journal of Tropical Medicine ; (12): 123-129, 2019.
Artigo em Chinês | WPRIM | ID: wpr-951251

RESUMO

Objective: To isolate and identify the antifungal compounds from Curcuma amada. Methods: The antifungal activity was measured by the diameter of colonies grown on Petri dish, microscopic observation, and CLSI microdilution methods. The antifungal compounds were isolated through bioactivity guided purification by using silica gel and high-performance liquid chromatography. Structural identification of the antifungal compounds was conducted using

8.
Rev. colomb. biotecnol ; 17(2): 22-32, jul.-dic. 2015. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-769069

RESUMO

El kéfir de agua (KA) es una bebida fermentada medianamente ácida elaborada con soluciones azucaradas y fermentada por un consorcio de microorganismos, principalmente bacterias ácido lácticas (BAL) y levaduras (LEV), embebidas en un polisacárido llamado gránulo de KA. La presencia de hongos y sus toxinas es un problema de la producción de alimentos, como Aspergillus ochraceus y sus micotoxinas especialmente en café y vino. Entre algunas alternativas que se han evaluado para su inhibición se incluyen las bacterias ácido lácticas y productos fermentados en general. El objetivo principal de esta investigación fue evaluar la capacidad del KA en inhibir o retrasar el crecimiento de A. ochraceus. Se emplearon 8 sobrenadantes libres de células (SLC) obtenidos de diferentes fermentaciones de panela con gránulos de KA y con diferentes concentraciones de ácidos orgánicos (láctico y acético). Se hicieron fermentaciones con gránulos de KA en solución de panela por periodos de 32,5 h, a 25, 30 y 37 °C. Se determinaron la cinética de acidificación; el incremento de biomasa y se hizo el recuento de los grupos de microorganismos que componen el gránulo. A 25 °C se determinó el mayor aumento de biomasa (92%). La temperatura de fermentación afectó el recuento de los microorganismos que conforman el gránulo, principalmente las BAL, disminuyendo su cantidad a la máxima temperatura de fermentación (37 °C) (1x10ˆ6 UFC ml-1), comparado con la mínima temperatura (25 °C) (6x10ˆ7 UFC ml-1). El fermento que presentó mayor actividad antifúngica fue el SLC5 (pH: 3,2; temperatura de fermentación: 30 °C). El poder inhibitorio se atribuyó a los ácidos orgánicos producidos durante la fermentación, aunque no se puede descartar que hayan actuado otras sustancias no cuantificadas. Se pudo comprobar que el KA puede fermentar y aumentar su biomasa en un sustrato como el agua de panela y que sus SLC tienen la capacidad de reducir el crecimiento de A. ochraceus.


Water kéfir (WK) is a moderately sour fermented beverage elaborated in sugar-containing solutions through fermentation by a microorganism consortium, principally lactic acid bacteria (LAB) and yeasts, embedded in a matrix of polysaccharide so-called WK grains. The presence of fungi and their toxins it is a problem for the food industry, such as Aspergillus ochraceus and their mycotoxin production especially in coffee and wine. Some alternatives that have been evaluated for their inhibition include lactic acid bacteria and generally fermented products. The main objective was to evaluate the capacity of WK to ferment a Colombian beverage made with Panela and to assess capability of this product to retard the germination of a common toxigenic fungi like Aspergillus ochraceus. 8 cell-free supernatants (CFS) were obtained from separate fermentations and with different organic acids (OA) concentrations (e. g., lactic and acetic). Different fermentations were conducted with WK in Panela broth during 32.5 h periods at 25, 30, and 37°C. We determined the kinetics of acidification of WK along with the corresponding increment in biomass and conducted a quantitation of microorganisms groups that composed the grain. The greatest biomass increase occurred at 25 °C (92%); but the fermentation temperature affected the composition of microorganisms conforming the grain, with the quantity of LAB decreasing at the highest fermentation temperatures (37 °C) (1x10ˆ6cfu ml-1), compared with the minimum temperature (25 °C) (6x10ˆ7 cfu ml-1). The CFS5 (pH 3.2; fermentation temperature 30 °C) exhibited the greatest antifungal activity. We attribute the inhibitory power of these ferments to the OA produced during fermentation, although we cannot discard the possibility of the action of other substances not specifically quantified. We concluded that WK can grow and fermentate Panela broth and that its CFS can exert an antifungal effect against A. ochraceus.

9.
Mycobiology ; : 59-66, 2012.
Artigo em Inglês | WPRIM | ID: wpr-729355

RESUMO

Antagonistic microorganisms against Rhizoctonia solani were isolated and their antifungal activities were investigated. Two hundred sixteen bacterial isolates were isolated from various soil samples and 19 isolates were found to antagonize the selected plant pathogenic fungi with varying degrees. Among them, isolate C9 was selected as an antagonistic microorganism with potential for use in further studies. Treatment with the selected isolate C9 resulted in significantly reduced incidence of stem-segment colonization by R. solani AG2-2(IV) in Zoysia grass and enhanced growth of grass. Through its biochemical, physiological, and 16S rDNA characteristics, the selected bacterium was identified as Bacillus subtilis subsp. subtilis. Mannitol (1%) and soytone (1%) were found to be the best carbon and nitrogen sources, respectively, for use in antibiotic production. An antibiotic compound, designated as DG4, was separated and purified from ethyl acetate extract of the culture broth of isolate C9. On the basis of spectral data, including proton nuclear magneric resonance (1H NMR), carbon nuclear magneric resonance (13C NMR), and mass analyses, its chemical structure was established as a stereoisomer of acetylbutanediol. Application of the ethyl acetate extract of isolate C9 to several plant pathogens resulted in dose-dependent inhibition. Treatment with the purified compound (an isomer of acetylbuanediol) resulted in significantly inhibited growth of tested pathogens. The cell free culture supernatant of isolate C9 showed a chitinase effect on chitin medium. Results from the present study demonstrated the significant potential of the purified compound from isolate C9 for use as a biocontrol agent as well as a plant growth promoter with the ability to trigger induced systemic resistance of plants.


Assuntos
Acetatos , Bacillus , Bacillus subtilis , Butileno Glicóis , Carbono , Quitina , Quitinases , Colo , DNA Ribossômico , Fungos , Incidência , Manitol , Nitrogênio , Plantas , Poaceae , Prótons , Rhizoctonia , Solo , Estereoisomerismo
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