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2.
PLoS Pathog ; 16(9): e1008800, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32913361

RESUMO

Soil-dwelling animals are at risk of pathogen infection in soils. When choosing nesting sites, animals could reduce this risk by avoiding contact with pathogens, yet there is currently little evidence. We tested this hypothesis using Solenopsis invicta as a model system. Newly mated queens of S. invicta were found to nest preferentially in soil containing more actinobacteria of Streptomyces and Nocardiopsis and to be attracted to two volatiles produced by these bacteria, geosmin and 2-methylisoborneol. Actinobacteria-rich soil was favored by S. invicta and this soil contained fewer putative entomopathogenic fungi than adjacent areas. Queens in such soil benefited from a higher survival rate. In culture, isolated actinobacteria inhibited entomopathogenic fungi, suggested that their presence may reduce the risk of fungal infection. These results indicated a soil-dwelling ant may choose nest sites presenting relatively low pathogen risk by detecting the odors produced by bacteria with anti-fungal properties.


Assuntos
Actinobacteria/fisiologia , Anti-Infecciosos/farmacologia , Formigas/fisiologia , Fungos/efeitos dos fármacos , Micoses/prevenção & controle , Comportamento de Nidação/efeitos dos fármacos , Compostos Orgânicos Voláteis/farmacologia , Animais , Formigas/microbiologia , Micoses/microbiologia , Microbiologia do Solo , Simbiose
3.
Nat Commun ; 11(1): 4864, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978392

RESUMO

The synthesis of customized glycoconjugates constitutes a major goal for biocatalysis. To this end, engineered glycosidases have received great attention and, among them, thioglycoligases have proved useful to connect carbohydrates to non-sugar acceptors. However, hitherto the scope of these biocatalysts was considered limited to strong nucleophilic acceptors. Based on the particularities of the GH3 glycosidase family active site, we hypothesized that converting a suitable member into a thioglycoligase could boost the acceptor range. Herein we show the engineering of an acidophilic fungal ß-xylosidase into a thioglycoligase with broad acceptor promiscuity. The mutant enzyme displays the ability to form O-, N-, S- and Se- glycosides together with sugar esters and phosphoesters with conversion yields from moderate to high. Analyses also indicate that the pKa of the target compound was the main factor to determine its suitability as glycosylation acceptor. These results expand on the glycoconjugate portfolio attainable through biocatalysis.


Assuntos
Tolerância a Medicamentos/fisiologia , Fungos/enzimologia , Fungos/metabolismo , Xilosidases/química , Xilosidases/metabolismo , Biocatálise , Domínio Catalítico , Fungos/efeitos dos fármacos , Glicoconjugados/metabolismo , Glicosídeo Hidrolases/metabolismo , Glicosídeos/química , Glicosilação , Concentração de Íons de Hidrogênio , Cinética , Modelos Moleculares , Mutagênese , Especificidade por Substrato , Talaromyces/enzimologia , Talaromyces/genética , Xilosidases/genética
4.
Ecotoxicol Environ Saf ; 202: 110959, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800231

RESUMO

Long-term field experiments were performed to evaluate the phytotoxic properties of fungal metabolites in oil-contaminated soil and to assess the impact of contamination on the allelopathic activity of soil mycobiota. Two contrasting soils of Northwest Russia (sandy and loamy podzols) exposed to oil contamination underwent changes in abundance and allelopathic activities of soil fungi. Shifts within the microbial community caused by oil contamination affected not only oil-decomposition rates but also ecotoxicity of contaminated soil. There were significant differences in soil toxicity dynamics between sandy and loamy podzols. Four years after contamination, ecotoxicity of loamy podzol decreased, whereas sandy podzol remained highly toxic even nine years after contamination. The abundance and allelopathic activity of fungi is correlated with hydrocarbon degradation dynamics. The soil fungal community demonstrated high allelopathic activity which decreased over time in fertile loamy podzolic soil, whereas in poor sandy podzolic soil it remained high over the nine-year monitoring period. The results illustrate how oil contamination may influence allelopathic interactions in soil and demonstrate the advantage of using fungal metabolite toxicity test for testing of oil-contaminated soil samples.


Assuntos
Fungos/efeitos dos fármacos , Hidrocarbonetos/toxicidade , Micotoxinas/toxicidade , Petróleo/toxicidade , Microbiologia do Solo , Poluentes do Solo/análise , Animais , Biodegradação Ambiental , Daphnia/efeitos dos fármacos , Daphnia/crescimento & desenvolvimento , Ecotoxicologia , Fungos/metabolismo , Hidrocarbonetos/análise , Micotoxinas/metabolismo , Petróleo/análise , Federação Russa , Solo/química , Testes de Toxicidade , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento
5.
BMC Microbiol ; 20(1): 265, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32847510

RESUMO

BACKGROUND: Acetic acid has been used to clean and disinfect surfaces in the household for many decades. The antimicrobial efficacy of cleaning procedures can be considered particularly important for young, old, pregnant, immunocompromised people, but may also concern other groups, particularly with regards to the COVID-19 pandemics. This study aimed to show that acetic acid exhibit an antibacterial and antifungal activity when used for cleaning purposes and is able to destroy certain viruses. Furthermore, a disinfecting effect of laundry in a simulated washing cycle has been investigated. RESULTS: At a concentration of 10% and in presence of 1.5% citric acid, acetic acid showed a reduction of > 5-log steps according to the specifications of DIN EN 1040 and DIN EN 1275 for the following microorganisms: P. aeruginosa, E. coli, S. aureus, L. monocytogenes, K. pneumoniae, E. hirae and A. brasiliensis. For MRSA a logarithmic reduction of 3.19 was obtained. Tests on surfaces according to DIN EN 13697 showed a complete reduction (> 5-log steps) for P. aeruginosa, E. coli, S. aureus, E. hirae, A. brasiliensis and C. albicans at an acetic acid concentration of already 5%. Virucidal efficacy tests according to DIN EN 14476 and DIN EN 16777 showed a reduction of ≥4-log-steps against the Modified Vaccinia virus Ankara (MVA) for acetic acid concentrations of 5% or higher. The results suggest that acetic acid does not have a disinfecting effect on microorganisms in a dosage that is commonly used for cleaning. However, this can be achieved by increasing the concentration of acetic acid used, especially when combined with citric acid. CONCLUSIONS: Our results show a disinfecting effect of acetic acid in a concentration of 10% and in presence of 1.5% citric acid against a variety of microorganisms. A virucidal effect against enveloped viruses could also be proven. Furthermore, the results showed a considerable antimicrobial effect of acetic acid when used in domestic laundry procedures.


Assuntos
Ácido Acético/farmacologia , Anti-Infecciosos/farmacologia , Betacoronavirus/efeitos dos fármacos , Ácido Cítrico/farmacologia , Infecções por Coronavirus/prevenção & controle , Desinfetantes/farmacologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Bactérias/efeitos dos fármacos , Desinfecção/métodos , Fungos/efeitos dos fármacos , Humanos , Norovirus/efeitos dos fármacos
6.
PLoS One ; 15(8): e0237263, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764812

RESUMO

BACKGROUND: Chronic infected wounds are generally difficult to manage and treatment can be particularly challenging in resource-limited settings where diagnostic testing is not readily available. In this study, the epidemiology of microbial pathogens in chronically infected wounds in rural Ghana was assessed to support therapeutic choices for physicians. METHODS: Culture-based bacterial diagnostics including antimicrobial resistance testing were performed on samples collected from patients with chronic wounds at a hospital in Asante Akim North Municipality, Ghana. Fungal detection was performed by broad-range fungal PCR and sequencing of amplicons. RESULTS: In total, 105 patients were enrolled in the study, from which 207 potential bacterial pathogens were isolated. Enterobacteriaceae (n = 84, 41%) constituted the most frequently isolated group of pathogens. On species level, Pseudomonas aeruginosa (n = 50, 24%) and Staphylococcus aureus (n = 28, 14%) were predominant. High resistance rates were documented, comprising 29% methicillin resistance in S. aureus as well as resistance to 3rd generation cephalosporins and fluoroquinolones in 33% and 58% of Enterobacteriaceae, respectively. One P. aeruginosa strain with carbapenem resistance was identified. The most frequently detected fungi were Candida tropicalis. CONCLUSIONS: The pathogen distribution in chronic wounds in rural Ghana matched the internationally observed patterns with a predominance of P. aeruginosa and S. aureus. Very high resistance rates discourage antibiotic therapy but suggest an urgent need for microbiological diagnostic approaches, including antimicrobial resistance testing to guide the management of patients with chronic wounds in Ghana.


Assuntos
Antibacterianos/farmacologia , Bactérias/isolamento & purificação , Fungos/isolamento & purificação , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Adulto , Idoso , Animais , Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Candida tropicalis/isolamento & purificação , Farmacorresistência Bacteriana , Farmacorresistência Fúngica , Feminino , Fungos/efeitos dos fármacos , Gana/epidemiologia , Hospitais de Distrito , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Infecção dos Ferimentos/epidemiologia , Adulto Jovem
7.
Bull Environ Contam Toxicol ; 105(4): 620-625, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32857223

RESUMO

Due to their ecological importance, fungi are suitable indicator organisms for anthropogenic stress. To estimate fungal biomass, the fungal membrane molecule ergosterol is often quantified as a proxy. Estimates based on ergosterol may, however, be distorted by exposure to demethylase inhibiting (DMI) fungicides, interfering with sterol synthesis. To test this hypothesis, we exposed ten fungal species to the DMI fungicide tebuconazole and measured concentrations of ergosterol and DNA per unit dry mass of the fungal hyphae. The latter served as alternative biomass proxy that is not specifically targeted by tebuconazole. Effects of tebuconazole on ergosterol concentrations were species-specific, while concentrations were on average reduced by 13%. In contrast, DNA concentrations were on average increased by 13%. We demonstrate that DMI fungicides - at close to field relevant levels - can distort fungal biomass estimation, complicating the use of this endpoint for environmental management.


Assuntos
Fungos/efeitos dos fármacos , Fungicidas Industriais/toxicidade , Triazóis/toxicidade , Biomarcadores , Biomassa , Ergosterol
8.
PLoS One ; 15(8): e0237567, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797097

RESUMO

Distinct morphological MgO nanoparticles (MgONPs) were synthesized using biomasses of Saussurea costus roots. The biomass of two varieties of Saussurea costus (Qustal hindi and Qustal bahri) were used in the green synthesis of MgONPs. The physical and chemical features of nanoparticles were confirmed by spectroscopic and microscopic techniques. The surface morphology of the obtained nanoparticles was detected at different magnifications by SEM and TEM microscopy and the size of nanoparticles were found to be 30 and 34 nm for Qustal hindi and Qustal bahri, respectively. The antimicrobial activity of the prepared MgONPs was screened against six pathogenic strains. The synthesized nanoparticles by Qustal bahri biomass exerted significant inhibition zones 15, 16, 18, 17, 14, and 10 mm against E. coli, P. aeruginosa, C. tropicalis and C. glabrata, S. aureus and B. subtilis as compared to those from Qustal hindi 12, 8 and 17 mm against B. subtilis, E. coli and C. tropicalis, respectively. MgONPs showed a potential cytotoxicity effect against MCF-7 breast cancer cell lines. Cellular investigations of MgONPs revealed that the prepared nanoparticles by Qustal bahri exhibited high cytotoxicity against MCF-7 cancer cell lines. IC50 values in MCF-7 cells were found to be 67.3% and 52.1% for MgONPs of Saussurea costus biomasses, respectively. Also, the photocatalytic activity of MgONPs of each Saussurea costus variety was comparatively studied. They exhibited an enhanced photocatalytic degradation of methylene blue after UV irradiation for 1 h as 92% and 59% for those prepared by Qustal bahri and Qustal hindi, respectively. Outcome of results revealed that the biosynthesized MgONPs showed promising biomedical potentials.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Óxido de Magnésio/farmacologia , Azul de Metileno/química , Saussurea/química , Anti-Infecciosos/química , Antineoplásicos/química , Bactérias/efeitos dos fármacos , Biomassa , Catálise , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Fungos/efeitos dos fármacos , Química Verde , Humanos , Células MCF-7 , Óxido de Magnésio/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Processos Fotoquímicos , Extratos Vegetais/química , Raízes de Plantas/química
9.
Int J Nanomedicine ; 15: 3983-3999, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606660

RESUMO

Introduction: In recent years, the use of cost-effective, multifunctional, environmentally friendly and simple prepared nanomaterials/nanoparticles have been emerged considerably. In this manner, different synthesizing methods were reported and optimized, but there is still lack of a comprehensive method with multifunctional properties. Materials and Methods: In this study, we aim to synthesis the copper oxide nanoparticles using Achillea millefolium leaf extracts for the first time. Catalytic activity was investigated by in situ azide alkyne cycloaddition click and also A3 coupling reaction, and optimized in terms of temperature, solvent, and time of the reaction. Furthermore, the photocatalytic activity of the synthesized nanoparticles was screened in terms of degradation methylene blue dye. Biological activity of the synthesized nanoparticles was evaluated in terms of antibacterial and anti-fungal assessments against Staphylococcus aureus, M. tuberculosis, E. coli, K. pneumoniae, P. mirabili, C. diphtheriae and S. pyogenes bacteria's and G. albicans, A. flavus, M. canis and G. glabrata fungus. In the next step, the biosynthesized CuO-NPs were screened by MTT and NTU assays. Results: Based on our knowledge, this is a comprehensive study on the catalytic and biological activity of copper oxide nanoparticles synthesizing from Achillea millefolium, which presents great and significant results (in both catalytic and biological activities) based on a simple and green procedure. Conclusion: Comprehensive biomedical and catalytic investigation of the biosynthesized CuO-NPs showed the mentioned method leads to synthesis of more eco-friendly nanoparticles. The in vitro studies showed promising and considerable results, and due to the great stability of these nanoparticles in a green media, effective biological activity considered as an advantageous.


Assuntos
Tecnologia Biomédica , Cobre/farmacologia , Nanopartículas Metálicas/química , Achillea/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Catálise , Sobrevivência Celular/efeitos dos fármacos , Reação de Cicloadição , Fungos/efeitos dos fármacos , Células Hep G2 , Humanos , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Solventes/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Difração de Raios X
10.
Arch Microbiol ; 202(9): 2509-2516, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32642829

RESUMO

Saccharothrix algeriensis NRRL B-24137 is an actinobacterium isolated from Algerian Saharan soil. This strain has the ability to produce several dithiolopyrrolone antibiotic derivatives depending on the precursors added to the culture medium. This group of antibiotics is known for their potent antimicrobial and anticancer activities. Holomycin is a member of the dithiolopyrrolone group of antibiotics, and has already been isolated from several species of actinobacteria belonging to the genus Streptomyces and also from some Gram-negative bacteria. In this study, holomycin was produced for the first time in the culture broth of a non-Streptomyces actinobacteria. This antibiotic was induced by adding 5 mM of L-cystine as precursor to the semi-synthetic fermentation broth of Sa. algeriensis NRRL B-24137 and then fully identified after HPLC purification. The minimum inhibitory concentrations (MIC) of holomycin were determined against several pathogenic microorganisms, including Escherichia coli ATCC 10536 Klebsiella pneumoniae CIP 82.91, Listeria monocytogenes CIP 82110, Staphylococcus aureus CIP 7625, Aspergillus carbonarius M333, Fusarium culmorum FC1, Candida albicans IPA 200. This antibiotic showed a broad-spectrum antimicrobial activity, inhibiting a variety of Gram-positive and Gram-negative bacteria, and micro-fungi.


Assuntos
Actinobacteria/metabolismo , Cistina/metabolismo , Lactamas/metabolismo , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Meios de Cultura/química , Fermentação , Fungos/efeitos dos fármacos , Lactamas/farmacologia , Testes de Sensibilidade Microbiana
11.
Arch Microbiol ; 202(9): 2525-2532, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32653933

RESUMO

The adverse effects of chemical pesticides on human health and environment cannot be ignored, hence it seems that novel alternative compounds should be applied to control plant pathogens. Among various alternative sources, natural compounds such as plant essential oils, plant extracts and recombinant antimicrobial peptides are of significance. The aim of the present study was to investigate antimicrobial activity of plants essential oils and plant extracts of six medicinal plants (Lippia citriodora, Ferula gummosa, Bunium persicum, Mentha piperita, Plantago major and Salvadora persica) along with a chimera peptide of camel lactoferrin, which is the most important antimicrobial component of camel milk, against Pseudomonas tolaasii and Trichoderma harzianum as pathogens of white button mushroom. The antibacterial activity test was conducted under in vitro conditions through disc diffusion method. The results showed that chimera camel lactoferrin peptide, with the highest amount of inhibitory zone (14.63 mm in 20 µg/mL concentration), has a significant difference in antibacterial activity compared to other treatments. Ferula gummosa conferred no antibacterial activity. Also, the results of antifungal effects indicated that plant essential oils and extracts have more antifungal activity than recombinant peptide. Generally, L. citriodora, B. persicum, M. piperita treatments could completely prevent growth of fungal in in vitro conditions. Therefore, using the mentioned plants can be a good replacement for reducing the chemical pesticides against pathogenic agents of button mushroom, without any adverse effects on environment and human health.


Assuntos
Lactoferrina/farmacologia , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Pseudomonas/efeitos dos fármacos , Trichoderma/efeitos dos fármacos , Agaricus , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antifúngicos/farmacologia , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Leite/química , Óleos Vegetais/farmacologia , Plantas Medicinais/química
12.
Ecotoxicol Environ Saf ; 201: 110847, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32554203

RESUMO

Bauxite residues (BR), commonly named red muds, are the saline-sodic waste produced during the extraction of alumina from bauxite. In this study, four kinds of BR were mixed at increasing concentrations with two soils in a mesososm experiment. Unamended BR from Provence (PRO) and Guinea (GUI) bauxite were selected, and Modified Bauxite Residues from PRO and GUI (MBR-PRO and MBR-GUI) were obtained by gypsum application and repeated leaching, in order to reduce their pH, electrical conductivity (EC) and exchangeable sodium percentage (ESP). Several indicators of microbial community functions and structure (growth of culturable bacteria; enzymatic activities; C-sourced substrates degradation (Biolog®); bacteria and fungi PCR-RFLP fingerprints) were measured after 35 days of incubation. Results showed that PRO residue had stronger negative effects than GUI on all the tested indicators. Residues modified by gypsum addition (MBR-PRO, MBR-GUI) were equally or sometimes less harmful compared to unamended residues. Microbial activities (bacterial growth and enzyme activities) were more inhibited than the diversity of microbial functions (Biolog®), and the structure of bacterial and fungal communities was not affected by increasing concentrations of bauxite residues. EC and ESP were the main factors explaining the inhibition of microbial activities, although the origin of bauxite residue is of great importance too.


Assuntos
Óxido de Alumínio/toxicidade , Sulfato de Cálcio/toxicidade , Microbiota/efeitos dos fármacos , Microbiologia do Solo , Poluentes do Solo/toxicidade , Solo/química , Óxido de Alumínio/análise , Óxido de Alumínio/química , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Sulfato de Cálcio/análise , Sulfato de Cálcio/química , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Poluentes do Solo/análise , Poluentes do Solo/química
13.
PLoS One ; 15(6): e0234390, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525917

RESUMO

Fungicide use in the United States to manage soybean diseases has increased in recent years. The ability of fungicides to reduce disease-associated yield losses varies greatly depending on multiple factors. Nonetheless, historical data are useful to understand the broad sense and long-term trends related to fungicide use practices. In the current study, the relationship between estimated soybean yield losses due to selected foliar diseases and foliar fungicide use was investigated using annual data from 28 soybean growing states over the period of 2005 to 2015. For national and regional (southern and northern United States) scale data, mixed effects modeling was performed considering fungicide use as a fixed and state and year as random factors to generate generalized R2 values for marginal (R2GLMM(m); contains only fixed effects) and conditional (R2GLMM(c); contains fixed and random effects) models. Similar analyses were performed considering soybean production data to see how fungicide use affected production. Analyses at both national and regional scales showed that R2GLMM(m) values were significantly smaller compared to R2GLMM(c) values. The large difference between R2 values for conditional and marginal models indicated that the variation of yield loss as well as production were predominantly explained by the state and year rather than the fungicide use, revealing the general lack of fit between fungicide use and yield loss/production at national and regional scales. Therefore, regression models were fitted across states and years to examine their importance in combination with fungicide use on yield loss or yield. In the majority of cases, the relationship was nonsignificant. However, the relationship between soybean yield and fungicide use was significant and positive for majority of the years in the study. Results suggest that foliar fungicides conferred yield benefits in most of the years in the study. Furthermore, the year-dependent usefulness of foliar fungicides in mitigating soybean yield losses suggested the possible influence of temporally fluctuating abiotic factors on the effectiveness of foliar fungicides and/or target disease occurrence and associated loss magnitudes.


Assuntos
Fungicidas Industriais/farmacologia , Doenças das Plantas/prevenção & controle , Soja/crescimento & desenvolvimento , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/microbiologia , Fungos/efeitos dos fármacos , Fungos/patogenicidade , Fungicidas Industriais/administração & dosagem , Fungicidas Industriais/provisão & distribução , Modelos Biológicos , Doenças das Plantas/microbiologia , Folhas de Planta/efeitos dos fármacos , Soja/efeitos dos fármacos , Soja/microbiologia , Análise Espaço-Temporal , Estados Unidos
14.
Arch Microbiol ; 202(7): 1985-1996, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32476047

RESUMO

A soft coral-derived fungus Penicillium sp. among other isolates e high antibacterial, anti-yeast and cytotoxic activities. The fungus, Penicillium sp. MMA, isolated from Sarcphyton glaucoma, afforded nine diverse compounds (1-9). Their structures were identified by 1D and 2 D NMR and ESI-MS spectroscopic data as two alkaloids: veridicatol (1), aurantiomide C (2); one sesquiterpene, aspterric acid (3); two carboxylic acids, 3,4-dihydroxy-benzoic acid; (4) and linoleic acid (5); three steroids, ergosterol (6), ß-Sitosterol (7), ß-Sitosterol glucoside (8) along with the sphingolipid, cerebroside A (9). Biologically, the antimicrobial, antioxidant, in vitro cytotoxicity and antibiofilm activities were studied in comparison with the fungal extract. The in silico computational studies were implemented to predict drug and lead likeness properties for 1-4. The fungus was taxonomically characterized by morphological and molecular biology (18srRNA) approaches.


Assuntos
Anti-Infecciosos , Antineoplásicos , Bactérias/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fungos/efeitos dos fármacos , Penicillium/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Oceano Índico , Estrutura Molecular , Penicillium/classificação , Penicillium/genética , Penicillium/metabolismo , RNA Ribossômico 18S/genética
15.
Int J Food Microbiol ; 330: 108713, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32512363

RESUMO

Sodium metabisulfite (SMBS), potassium metabisulfite (PMBS), aluminum sulfate (AlS) and aluminum potassium sulfate (AlPS), common sulfur-containing salts used as food additives, were evaluated for their antifungal activity against Penicillium digitatum, Penicillium italicum and Geotrichum citri-aurantii, the most economically important pathogens causing postharvest diseases of citrus fruits. In vitro radial mycelial growth was measured on potato dextrose agar (PDA) Petri dishes amended with five different concentrations of the salts (10, 20, 30, 50, 100 mM) after 7 d of incubation at 25 °C. SMBS and PMBS at all concentrations, and AIS and AIPS above 20 mM, completely inhibited the growth of these fungi. The curative antifungal activity of the four salts to control citrus green (GM) and blue (BM) molds and sour rot (SR) was evaluated on 'Valencia' oranges artificially inoculated in rind wounds with P. digitatum, P. italicum and G. citri-aurantii, respectively. In vivo primary screenings showed no significant antifungal activity of AlS and AlPS to control the three diseases at any dose tested, but SMBS and PMBS reduced the incidence and severity of GM, BM and SR at various concentrations. Effective salts and concentrations were selected for in vivo dip treatments in small-scale trials. Dips at room temperature (20 °C) in SMBS and PMBS at 20 and 50 mM for 60 or 120 s significantly reduced the incidence and severity of GM and BM, with PMBS at 50 mM for 120 s the most effective treatment. Conversely, dips in SMBS and PMBS at 50 mM for 60 or 120 s did not reduce SR incidence and severity. SMBS and PMBS treatments are potentially new tools to be included in reduced-risk non-polluting strategies to control Penicillium diseases, but not SR, on citrus fruits.


Assuntos
Antifúngicos/farmacologia , Citrus/microbiologia , Aditivos Alimentares/farmacologia , Doenças das Plantas/prevenção & controle , Enxofre/farmacologia , Aditivos Alimentares/química , Conservação de Alimentos/métodos , Frutas/microbiologia , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Temperatura , Fatores de Tempo
16.
Arch Microbiol ; 202(9): 2391-2400, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32588084

RESUMO

An amplicon metagenomic approach based on the ITS1 region of fungal rDNA was employed to identify the composition of fungal communities associated with diseases of pear fruits during postharvest storage. The sampled fruits were harvested at an orchard using routine management practices involving treatments with various chemical fungicides and were transferred to a storage packinghouse. Effective tags of reading sequences clustered into 53 OTUs whereas Ascomycota was the dominant phylum (83.4%) followed by Basidiomycota (15.8%). Our results revealed that four genera, Penicillium, Rhodotorula, Alternaria and Cladosporium were the most abundant representing 59-95% of the relative abundance per sample. The interruption of chemical treatments during the last month before harvest altered the structure of the fungal community of fruits among untreated and treated samples, mainly in cases of relative abundance of Penicillium and Rhodotorula genera. We hypothesize that various antagonistic interactions might occur on fruit surfaces among the detected fungal genera whose relative abundances were affected by fungicide treatments. Interestingly, some common pre- and postharvest pear fungal pathogens were either less present (such as Moniliana), or undetected (such as Aspergillus, Venturia and Septoria) in untreated and treated samples.


Assuntos
Microbiologia de Alimentos , Frutas/microbiologia , Fungos , Metagenômica , Micobioma , Pyrus/microbiologia , Fungos/classificação , Fungos/efeitos dos fármacos , Fungos/genética , Fungicidas Industriais/farmacologia , Micobioma/efeitos dos fármacos , Micobioma/genética
17.
Int J Nanomedicine ; 15: 2541-2553, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368039

RESUMO

Background: In the emerging field of nanotechnology, copper oxide (CuO) nanomaterials are considered to be one of the most important transition metal oxides owing to its fascinating properties. Its synthesis from green chemistry principles is gaining importance as next-generation antibiotics due to its simplicity, eco-friendliness, and cost-effectiveness. In the present study, CuO nanorods (CuO NRs) were synthesized from the aqueous fruit extract of Momordica charantia and characterized using different analytical techniques. Further, the biomedical therapeutic potential was evaluated against multi-drug resistant microbial strains. Materials and Methods: To synthesize CuO NRs, 0.1M of CuSO4.5H2O solution was added to aqueous extract of Momordica charantia in a 1:3 (v/v) ratio (pH=11) and heated at 50°C followed by washing and drying. The synthesized CuO NRs were subjected to characterization using different analytical techniques such as UV visible spectroscopy, zeta sizer equipped with zeta potential, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). Further, the application as a biomedical therapeutic potential was evaluated in vitro using well diffusion method against eleven multidrug-resistant clinical bacterial strains, a fungus- Trichophyton rubrum and in ovo against the R2B virus using haemagglutination (HA) test. Results: Characterization was preliminarily done by the spectral study that confirms the absorbance band at 245nm. FTIR analysis at 628 cm-1 peak identified copper oxide vibration. SEM analysis revealed agglomerated particle clusters. However, with TEM clear nanorods of average diameter of 61.48 ± 2 nm were observed. EDAX confirmed CuO formation while XRD showed a typical monoclinic structure with 6 nm crystallite size. Biological screening of CuO NRs showed significant results against both in vitro and in ovo methods. Significant inhibitory activity (p<0.0001) was noted against most of the resistant human pathogenic strains including both Gram-positive and Gram-negative bacteria. The highest efficacy was observed against Bacillus cereus with a 31.66 mm zone of inhibition. Besides, the therapeutic potential of CuO NRs against Corynebacterium xerosis, Streptococcus viridians and R2B strain of Newcastle disease is reported for the first time. Conclusion: Based on the present results, it could be expected that green synthesized CuO NRs would find potential applications in the field of nanomedicine.


Assuntos
Antibacterianos/farmacologia , Cobre/farmacologia , Química Verde , Momordica charantia/química , Nanoestruturas/química , Animais , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Galinhas , Fungos/efeitos dos fármacos , Testes de Hemaglutinação , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Nanoestruturas/ultraestrutura , Nanotubos/química , Nanotubos/ultraestrutura , Tamanho da Partícula , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Difração de Raios X
18.
PLoS One ; 15(5): e0229630, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401759

RESUMO

Chromoblastomycosis (CBM) is a chronic subcutaneous mycosis caused by traumatic implantation of many species of black fungi. Due to the refractoriness of some cases and common recurrence of CBM, a more effective and less time-consuming treatment is mandatory. The aim of this study was to identify compounds with in vitro antifungal activity in the Pathogen Box® compound collection against different CBM agents. Synergism of these compounds with drugs currently used to treat CBM was also assessed. An initial screening of the drugs present in this collection at 1 µM was performed with a Fonsecaea pedrosoi clinical strain according to the EUCAST protocol. The compounds with activity against this fungus were also tested against other seven etiologic agents of CBM (Cladophialophora carrionii, Phialophora verrucosa, Exophiala jeanselmei, Exophiala dermatitidis, Fonsecaea monophora, Fonsecaea nubica, and Rhinocladiella similis) at concentrations ranging from 0.039 to 10 µM. The analysis of potential synergism of these compounds with itraconazole and terbinafine was performed by the checkerboard method. Eight compounds inhibited more than 60% of the F. pedrosoi growth: difenoconazole, bitertanol, iodoquinol, azoxystrobin, MMV688179, MMV021013, trifloxystrobin, and auranofin. Iodoquinol produced the lowest MIC values (1.25-2.5 µM) and MMV688179 showed MICs that were higher than all compounds tested (5 - >10 µM). When auranofin and itraconazole were tested in combination, a synergistic interaction (FICI = 0.37) was observed against the C. carrionii isolate. Toxicity analysis revealed that MMV021013 showed high selectivity indices (SI ≥ 10) against the fungi tested. In summary, auranofin, iodoquinol, and MMV021013 were identified as promising compounds to be tested in CBM models of infection.


Assuntos
Antifúngicos/farmacologia , Cromoblastomicose/tratamento farmacológico , Sinergismo Farmacológico , Fungos/patogenicidade , Acetatos/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/patogenicidade , Auranofina/farmacologia , Compostos de Bifenilo/farmacologia , Cromoblastomicose/microbiologia , Cromoblastomicose/patologia , Dioxolanos/farmacologia , Exophiala/efeitos dos fármacos , Exophiala/patogenicidade , Fungos/efeitos dos fármacos , Humanos , Iminas/farmacologia , Iodoquinol/farmacologia , Pirimidinas/farmacologia , Estrobilurinas/farmacologia , Triazóis/farmacologia
19.
World J Microbiol Biotechnol ; 36(5): 77, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32399738

RESUMO

Protease mediated proteolysis has been widely implicated in virulence of necrotrophic fungal pathogens. This is counteracted in plants by evolving new and effective antimicrobial peptides (AMP) that constitute important components of innate immune system. Peptide extraction from rhizome of Zingiber zerumbet was optimized using ammonium sulphate (50-80% w/v) and acetone (60 and 100% v/v) with maximal protein recovery of 1.2 ± 0.4 mg/g obtained using 100% acetone. Evaluation of inhibitory potential of Z. zerumbet rhizome protein extract to prominent hydrolases of necrotrophic Pythium myriotylum revealed maximal inhibition of proteases (75.8%) compared to other hydrolytic enzymes. Protein was purified by Sephacryl S200HR resin resulting in twofold purification and protease inhibition of 84.4%. Non-reducing polyacrylamide gel electrophoresis (PAGE) of the fractions yielded two bands of 75 kDa and 25 kDa molecular size. Peptide mass fingerprint of the protein bands using matrix assisted laser desorption/ionization (MALDI)-time of flight (TOF) mass spectroscopy (MS) and subsequent MASCOT searches revealed peptide match to methylesterase from Arabidopsis thaliana (15%) and to hypothetical protein from Oryza sativa (98%) respectively. Further centrifugal filter purification using Amicon Ultra (10,000 MW cut-off) filter, yielded a prominent band of 25 kDa size. Concentration dependent inhibition of zoospore viability by Z. zerumbet AMP designated as ZzAMP was observed with maximal inhibition of 89.5% at 4 µg protein and an IC50 value of 0.59 µg. Studies are of particular relevance in the context of identifying the molecules involved in imparting below ground defense in Z. zerumbet as well in development of AMPs as potential candidate molecules for control of necrotrophic pathogens of agricultural relevance.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeo Hidrolases/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pythium/efeitos dos fármacos , Rizoma/microbiologia , Zingiberaceae/microbiologia , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/química , Arabidopsis , Inibidores Enzimáticos , Fungos/efeitos dos fármacos , Oryza , Peptídeos/farmacologia , Extratos Vegetais/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Zingiberaceae/crescimento & desenvolvimento
20.
Mar Drugs ; 18(4)2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32344725

RESUMO

Sponge-associated fungi are attractive targets for the isolation of bioactive natural products with different pharmaceutical purposes. In this investigation, 20 fungi were isolated from 10 different sponge specimens. One isolate, the fungus Penicillium citrinum strain WK-P9, showed activity against Bacillus subtilis JH642 when cultivated in malt extract medium. One new and three known citrinin derivatives were isolated from the extract of this fungus. The structures were elucidated by 1D and 2D NMR spectroscopy, as well as LC-HRMS. Their antibacterial activity against a set of common human pathogenic bacteria and fungi was tested. Compound 2 showed moderate activity against Mycobacterium smegmatis ATCC607 with a minimum inhibitory concentration (MIC) of 32 µg/mL. Compound 4 exhibited moderate growth inhibition against Bacillus subtilis JH642, B. megaterium DSM32, and M. smegmatis ATCC607 with MICs of 16, 16, and 32 µg/mL, respectively. Furthermore, weak activities of 64 µg/mL against B. subtilis DSM10 and S. aureus ATCC25923 were observed for compound 4.


Assuntos
Antibacterianos/isolamento & purificação , Citrinina/isolamento & purificação , Penicillium/química , Poríferos/microbiologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Citrinina/química , Citrinina/farmacologia , Fungos/efeitos dos fármacos , Indonésia , Testes de Sensibilidade Microbiana , Penicillium/isolamento & purificação
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