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1.
J Nat Prod ; 85(11): 2667-2674, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36346918

RESUMO

Chromatographic separation on the liquid-state fermented products produced by the fungal strain Alternaria alstroemeriae Km2286 isolated from the littoral medicinal herb Atriplex maximowicziana Makino resulted in the isolation of compounds 1-9. Structures were determined by spectroscopic analysis as four undescribed perylenequinones, altertromins A-D (1-4), along with altertoxin IV (5), altertoxin VIII (6), stemphyperylenol (7), tenuazonic acid (8), and allo-tenuazonic acid (9). Compounds 1-6 exhibited antiviral activities against Epstein-Barr virus (EBV) with EC50 values ranging from 0.17 ± 0.07 to 3.13 ± 0.31 µM and selectivity indices higher than 10. In an anti-neuroinflammatory assay, compounds 1-4, 6, and 7 showed inhibitory activity of nitric oxide production in lipopolysaccharide-induced microglial BV-2 cells, with IC50 values ranging from 0.33 ± 0.04 to 4.08 ± 0.53 µM without significant cytotoxicity. This is the first report to describe perylenequinone-type compounds with potent anti-EBV and anti-neuroinflammatory activities.


Assuntos
Alternaria , Anti-Inflamatórios , Antivirais , Atriplex , Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Perileno , Plantas Medicinais , Quinonas , Humanos , Alternaria/química , Alternaria/isolamento & purificação , Atriplex/microbiologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/efeitos dos fármacos , Estrutura Molecular , Perileno/química , Perileno/isolamento & purificação , Perileno/farmacologia , Plantas Medicinais/microbiologia , Quinonas/química , Quinonas/isolamento & purificação , Quinonas/farmacologia , Ácido Tenuazônico/química , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , Antivirais/farmacologia
2.
Braz J Microbiol ; 52(4): 1791-1805, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34339015

RESUMO

Endophytes are regarded with immense potentials in terms of plant growth promoting (PGP) elicitors and mimicking secondary metabolites of medicinal importance. Here in the present study, we explored Bacopa monnieri plants to isolate, identify fungal endophytes with PGP elicitation potentials, and investigate secretion of secondary metabolites such as bacoside and withanolide content under in vitro conditions. Three fungal endophytes isolated (out of 40 saponin producing isolates) from leaves of B. monnieri were examined for in vitro biosynthesis of bacosides. On morphological, biochemical, and molecular identification (ITS gene sequencing), the isolated strains SUBL33, SUBL51, and SUBL206 were identified as Nigrospora oryzae (MH071153), Alternaria alternata (MH071155), and Aspergillus terreus (MH071154) respectively. Among these strains, SUBL33 produced highest quantity of Bacoside A3 (4093 µg mL-1), Jujubogenin isomer of Bacopasaponin C (65,339 µg mL-1), and Bacopasaponin C (1325 µg mL-1) while Bacopaside II (13,030 µg mL-1) was produced by SUBL51 maximally. Moreover, these aforementioned strains also produced detectable concentration of withanolides-Withaferrin A, Withanolide A (480 µg mL-1), and Withanolide B (1024 µg mL-1) respectively. However, Withanolide A was not detected in the secondary metabolites of strain SUBL51. To best of our knowledge, the present study is first reports of Nigrospora oryzae as an endophyte in B. monnieri with potentials of biosynthesis of economically important phytomolecules under in vitro conditions.


Assuntos
Bacopa , Endófitos , Fungos , Saponinas , Vitanolídeos , Alternaria/genética , Alternaria/isolamento & purificação , Alternaria/metabolismo , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Ascomicetos/metabolismo , Aspergillus/genética , Aspergillus/isolamento & purificação , Aspergillus/metabolismo , Bacopa/microbiologia , Endófitos/genética , Endófitos/isolamento & purificação , Endófitos/metabolismo , Fungos/genética , Fungos/isolamento & purificação , Fungos/metabolismo , Folhas de Planta/microbiologia , Saponinas/biossíntese , Vitanolídeos/metabolismo
3.
Chem Biodivers ; 17(4): e2000043, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32112467

RESUMO

Alternariol and altenuisol were isolated as the major phytotoxins produced by an Alternaria sp. pathogenic fungus of the invasive weed Xanthium italicum. Altenuisol exhibited stronger phytotoxic effect compared with alternariol. At 10 µg/mL, alternariol and altenuisol promoted root growth of the monocot plant Pennisetum alopecuroides by 11.1 % and 75.2 %, respectively, however, inhibitory activity was triggered by the increase of concentration, with root elongation being suppressed by 35.5 % and 52.0 % with alternariol and altenuisol at 1000 µg/mL, respectively. Alternariol slightly inhibited root length of the dicot plant Medicago sativa at 10-1000 µg/mL, whereas altenuisol stimulated root growth by 51.0 % at 10 µg/mL and inhibited root length by 43.4 % at 200 µg/mL. Alternariol and altenuisol did not exert strong regulatory activity on another dicot plant, Amaranthus retroflexus, when tested concentration was low, however, when the concentration reached 1000 µg/mL, they reduced root length by 68.1 % and 51.0 %, respectively. Alternariol and altenuisol exerted similar effect on shoot growth of three tested plants but to a lesser extent. It is noteworthy to mention that this is the first report on the phytotoxicity of altenuisol.


Assuntos
Alternaria/química , Micotoxinas/química , Xanthium/microbiologia , Alternaria/isolamento & purificação , Alternaria/metabolismo , Amaranthus/efeitos dos fármacos , Amaranthus/crescimento & desenvolvimento , Espécies Introduzidas , Lactonas/química , Lactonas/isolamento & purificação , Lactonas/farmacologia , Micotoxinas/isolamento & purificação , Micotoxinas/farmacologia , Pennisetum/efeitos dos fármacos , Pennisetum/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia
4.
J Agric Food Chem ; 68(4): 1126-1135, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31891261

RESUMO

Phenylpropanoid (PPPN) compounds are widely used in agriculture, medical, food, and cosmetic industries because of their multiple bioactivities. Alternaria sp. MG1, an endophytic fungus isolated from grape, is a new natural source of PPPNs. However, the PPPN biosynthesis pathway in MG1 tends to be suppressed under normal growth conditions. Starvation has been reported to stimulate the PPPN pathway in plants, but this phenomenon has not been well studied in endophytic fungi. Here, metabolomics analysis was used to examine the profile of PPPN compounds, and quantitative reverse transcription-polymerase chain reaction was used to detect the expression of key genes in the PPPN biosynthesis pathway under starvation conditions. Starvation treatment significantly increased the accumulation of shikimate and PPPN compounds and upregulated the expression of key genes in their biosynthesis pathways. In addition to previously reported PPPNs, sinapate, 4-hydroxystyrene, piceatannol, and taxifolin were also detected under starvation treatment. These findings suggest that starvation treatment provides an effective way to optimize the production of PPPN compounds and may permit the investigation of compounds that are undetectable under normal conditions. Moreover, the diversity of its PPPNs makes strain MG1 a rich repository of valuable compounds and an extensive genetic resource for future studies.


Assuntos
Alternaria/metabolismo , Endófitos/metabolismo , Vitis/metabolismo , Vitis/microbiologia , Alternaria/genética , Alternaria/isolamento & purificação , Vias Biossintéticas , Ácidos Cumáricos/metabolismo , Endófitos/genética , Endófitos/isolamento & purificação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Metabolômica , Fenóis/metabolismo , Quercetina/análogos & derivados , Quercetina/biossíntese , Metabolismo Secundário , Estilbenos/metabolismo
5.
Int J Food Microbiol ; 311: 108333, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31669927

RESUMO

Large amounts of tomato fruits and derived products are produced in China and may be contaminated by Alternaria mycotoxins, which may have the potential risks for human health. There is thus an increasing interest in reducing the mycotoxins. In the present study, 26 Alternaria strains isolated from tomato black rots were identified according to morphological and molecular grounds, and their mycotoxigenic abilities for alternariol (AOH), alternariol monomethyl-ether (AME) and tenuazonic acid (TeA) were also investigated. The results showed that A. alternate was the predominant species with incidence values of 65.4% (17/26), followed by A. brassicae (7/26) and A. tenuissima (2/26). A. alternate isolates showed the highest capacity for AOH, AME and TeA production among the studied isolates either in vitro or in vivo, suggested that A. alternata may be the most important mycotoxin-producing species in tomato fruits. Thus, UV-C irradiation was used to reduce the mycotoxin produced by A. alternata in our study. The results showed that low dose of UV-C irradiation (0.25 kJ/m2) could effectively inhibit mycotoxins production and penetration in tomatoes. Upon treatment with UV-C, there was 79.6, 76.4 and 51.4% of reduction in AOH, AME and TeA penetration when compared to untreated fruits. This may be associated with the enhanced phenolics by UV-C irradiation. In fact, the induced phenolics were including p-coumaric, ferulic and pyrocatechuic acids, of which p-coumaric acid (1.0 mM) displayed the highest reduction of TeA with 60.2%, whereas ferulic acid (1.0 mM) showed strong inhibitory effects on the AOH and AME production by 59.4 and 79.1%, respectively. Therefore, the application of UV-C irradiation seems to be a promising method for reducing the potential risk of Alternaria mycotoxins in fruits and also for enhancing phenolics of processing products.


Assuntos
Alternaria/metabolismo , Lactonas/análise , Micotoxinas/biossíntese , Solanum lycopersicum/microbiologia , Ácido Tenuazônico/biossíntese , Raios Ultravioleta , Alternaria/classificação , Alternaria/isolamento & purificação , China , Ácidos Cumáricos/metabolismo , Frutas/química , Frutas/microbiologia , Propionatos/metabolismo
6.
BMC Microbiol ; 19(1): 205, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477005

RESUMO

BACKGROUND: Cross-resistance, a phenomenon that a pathogen resists to one antimicrobial compound also resists to one or several other compounds, is one of major threats to human health and sustainable food production. It usually occurs among antimicrobial compounds sharing the mode of action. In this study, we determined the sensitivity profiles of Alternaria alternata, a fungal pathogen which can cause diseases in many crops to two fungicides (mancozeb and difenoconazole) with different mode of action using a large number of isolates (234) collected from seven potato fields across China. RESULTS: We found that pathogens could also develop cross resistance to fungicides with different modes of action as indicated by a strong positive correlation between mancozeb and difenoconazole tolerances to A. alternata. We also found a positive association between mancozeb tolerance and aggressiveness of A. alternata, suggesting no fitness penalty of developing mancozeb resistance in the pathogen and hypothesize that mechanisms such as antimicrobial compound efflux and detoxification that limit intercellular accumulation of natural/synthetic chemicals in pathogens might account for the cross-resistance and the positive association between pathogen aggressiveness and mancozeb tolerance. CONCLUSIONS: The detection of cross-resistance among different classes of fungicides suggests that the mode of action alone may not be an adequate sole criterion to determine what components to use in the mixture and/or rotation of fungicides in agricultural and medical sects. Similarly, the observation of a positive association between the pathogen's aggressiveness and tolerance to mancozeb suggests that intensive application of site non-specific fungicides might simultaneously lead to reduced fungicide resistance and enhanced ability to cause diseases in pathogen populations, thereby posing a greater threat to agricultural production and human health. In this case, the use of evolutionary principles in closely monitoring populations and the use of appropriate fungicide applications are important for effective use of the fungicides and durable infectious disease management.


Assuntos
Alternaria/efeitos dos fármacos , Farmacorresistência Fúngica , Fungicidas Industriais/farmacologia , Alternaria/genética , Alternaria/isolamento & purificação , Alternaria/fisiologia , China , Dioxolanos/farmacologia , Maneb/farmacologia , Doenças das Plantas/microbiologia , Solanum tuberosum/microbiologia , Triazóis/farmacologia , Zineb/farmacologia
7.
J Appl Microbiol ; 127(5): 1468-1478, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31403229

RESUMO

AIMS: Medicinal plant-associated endophytic fungi are important sources of precious bioactive compounds, contributing more than 80% of the natural drugs for various ailments. The present study was aimed at evaluating the anticancer activity of the crystallized compound alternariol methyl ether (AME) against hepatocellular carcinoma (HCC) both in vitro and in vivo from an endophytic fungus residing in the medicinal plant Vitex negundo. METHODS AND RESULTS: The secondary metabolites from the endophytic fungus Alternaria alternata MGTMMP031 were isolated. Purification and characterization of the compound was performed and the potential compound was identified as AME. The crystal structure of AME was unambiguously confirmed by X-ray analysis. AME has been checked for its antibacterial and anticancer properties which showed its effectiveness against various bacteria and demonstrated marked anti-proliferative activity against the human HCC cells (HUH-7) both in vitro and in vivo. Mode of actions included cell cycle arrest, reducing the level of markers enzymes of liver cancer and preventing tumour growth. CONCLUSIONS: Alternariol methyl ether acts as a potential therapeutic target against HCC. The compound was isolated and the crystal structure was obtained for the first time from the endophytic fungus A. alternata MGTMMP031. In the present study, the crystallized structure of AME was obtained by slow evaporation technique. It can be concluded that AME acts as a potential therapeutic target against HCC. SIGNIFICANCE AND IMPACT OF THE STUDY: Endophytic fungi residing in the medicinal plants have strong biological significance and bioactive compounds from these fungi provide better therapeutic targets against diseases.


Assuntos
Alternaria/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Endófitos/química , Lactonas/isolamento & purificação , Lactonas/farmacologia , Éteres Metílicos/química , Plantas Medicinais/microbiologia , Alternaria/isolamento & purificação , Alternaria/metabolismo , Antineoplásicos/isolamento & purificação , Antineoplásicos/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/fisiopatologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Cristalização , Endófitos/isolamento & purificação , Endófitos/metabolismo , Humanos , Lactonas/química , Lactonas/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/fisiopatologia , Éteres Metílicos/isolamento & purificação , Éteres Metílicos/farmacologia , Metabolismo Secundário
8.
World J Microbiol Biotechnol ; 35(5): 74, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053977

RESUMO

In the present study, an endophytic fungal strain was isolated from its non-Taxus host plant Terminalia arjuna and identified as Alternaria brassicicola based on its morphological characteristics and internal transcribed spacer sequence analysis. This fungus was grown in potato dextrose broth and analyzed for the presence of taxol by using chromatographic and spectrometric techniques. The ethyl acetate extract of A.brassicicola was subjected to column chromatography. Among the different fractions, the fraction 7 showed positive to taxol, which was further confirmed by UV absorption, HPLC, FTIR spectra and LC-ESI-MS by comparing with the authentic taxol (Paclitaxel). The peaks of fraction 7 obtained by UV spectroscopy, FTIR and HPLC analysis were quite similar to that of standard taxol confirming the presence of taxol. A parent ion peak of m/z 854.95 was observed in the LC-ESI-MS spectrum which was similar to paclitaxel with reported m/z of 854 [M+H]+ ion. A. brassicicola produced about 140.8 µg/l taxol as quantified through HPLC. Present study results suggest that the endophytic fungus A.brassicicola serves as a potential source for the production of taxol isolated from non-Taxus plant.


Assuntos
Alternaria/isolamento & purificação , Alternaria/metabolismo , Paclitaxel/química , Paclitaxel/isolamento & purificação , Plantas Medicinais/microbiologia , Terminalia/microbiologia , Alternaria/classificação , Cromatografia , Cromatografia Líquida de Alta Pressão , Endófitos/isolamento & purificação , Endófitos/metabolismo , Fermentação , Espectrometria de Massas , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Environ Monit Assess ; 190(10): 608, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30255210

RESUMO

This quantitative and qualitative study aimed to evaluate the level of fungal contamination in computer keyboards from an Integrated Health Center (IHC) at Piauí, Brazil, and to evaluate the efficacy of 50% sodium bicarbonate and 50% alcoholic vinegar solutions to eliminate these microorganisms. Ten keyboards from six sectors of the IHC were chosen randomly, and the collection was performed in three situations: (i) before of disinfection, (ii) after disinfection with solution of sodium bicarbonate, and (iii) after disinfection with solution of alcoholic vinegar. Samples were inoculated in Petri dishes with dextrose agar potato plus chloramphenicol and incubated at room temperature for 72 h. All keyboards were contaminated with opportunistic fungi, with Cladosporium cladosporioides (29.4%) being the most frequent species, followed by Curvularia lunata (17.6%) and Aspergillus niger, Alternaria alternata, and Curvularia clavata with 11.8% each. The two solutions were proven to be efficient in eliminating fungal contamination; however, the sodium bicarbonate solution caused esthetic damages in keyboards. In addition, this study is the first report of the antifungal activity of alcoholic vinegar in filamentous fungi. Based on our findings, we suggest a daily disinfection of keyboards with a 50% vinegar solution plus adequate hygiene from the hands of professionals before and after the use of the computer and its annexes, as key actions to reduce nosocomial infections, particularly in economically disadvantaged countries.


Assuntos
Ácido Acético/farmacologia , Alternaria/efeitos dos fármacos , Antifúngicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Cladosporium/efeitos dos fármacos , Desinfetantes/farmacologia , Desinfecção/métodos , Controle de Infecções/métodos , Bicarbonato de Sódio/farmacologia , Alternaria/isolamento & purificação , Aspergillus niger/isolamento & purificação , Brasil , Cladosporium/isolamento & purificação , Computadores , Monitoramento Ambiental , Humanos
10.
Curr Microbiol ; 74(9): 1083-1088, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28653110

RESUMO

Early blight, caused by Alternaria solani, is one of the most devastating diseases of potato that causes severe yield loss worldwide. The infected potato debris existed in the soil serve as the initial infection sources for the next growing potato. Current identification of A. solani in soil relies primarily on cultural and morphological characteristics, which are time-consuming and inaccurate. In this study, a semi-nested PCR method was developed using primers based on internal transcribed spacer region that is specific to A. solani. 20 isolates including 6 Alternaria species and 10 other species of common potato pathogens were used to examine the specificity of the primers. The primer set ptAsQ-F/ptAs-R was highly specific to A. solani, as a product of 251 bp was amplified only from A. solani isolates and no amplification signal was observed from other tested species. The sensitivity of this method determined using A. solani genomic DNA was 10 fg. This PCR assay was also successfully employed to detect A. solani in soil with the detection sensitivity of one conidia spore in 0.5 g of soil. To the best of our knowledge, this is the first report of molecular detection of A. solani in soil, which provides a useful tool for early and rapid detection of early blight in soil before next growing season.


Assuntos
Alternaria/classificação , Alternaria/isolamento & purificação , Técnicas Microbiológicas/métodos , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase/métodos , Microbiologia do Solo , Solanum tuberosum/microbiologia , Alternaria/genética , Primers do DNA/genética , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Sensibilidade e Especificidade , Fatores de Tempo
11.
Molecules ; 22(5)2017 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-28481313

RESUMO

Two new compounds isobenzofuranone A (1) and indandione B (2), together with eleven known compounds (3-13) were isolated from liquid cultures of an endophytic fungus Alternaria sp., which was obtained from the medicinal plant Morinda officinalis. Among them, the indandione (2) showed a rarely occurring indanone skeleton in natural products. Their structures were elucidated mainly on the basis of extensive spectroscopic data analysis. All of the compounds were evaluated with cytotoxic and α-glucosidase inhibitory activity assays. Compounds 11 and 12 showed significant inhibitory activities against four tumor cell lines; MCF-7, HepG-2, NCI-H460 and SF-268, with IC50 values in the range of 1.91-9.67 µM, and compounds 4, 5, 9, 10, 12 and 13 showed excellent inhibitory activities against α-glucosidase with IC50 values in the range of 12.05-166.13 µM.


Assuntos
Alternaria , Furanos , Indanos , Morinda/microbiologia , Alternaria/isolamento & purificação , Alternaria/metabolismo , Furanos/análise , Furanos/química , Furanos/metabolismo , Indanos/análise , Indanos/química , Indanos/metabolismo
12.
Transpl Infect Dis ; 19(3)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28295973

RESUMO

Alternaria species have been reported as a rare cause of fungal infection in organ and stem cell transplant recipients, but to date, no reports have been published of infection in humans caused by Alternaria rosae. Here, we report cutaneous A. rosae infection in a 66-year-old farmer with a history of primary myelofibrosis who had undergone allogeneic unrelated donor hematopoietic stem cell transplantation. Forty-nine days post transplant, he presented with a nodule on the thumb with no findings suggestive of disseminated infection. Pathology, culture, and molecular speciation showed the nodule was caused by cutaneous A. rosae. He had been on voriconazole as antifungal prophylaxis, but was found to have a subtherapeutic voriconazole level. He was switched to posaconazole based on published in vitro data showing its superior efficacy in Alternaria treatment. Susceptibility testing showed that the A. rosae isolate was indeed susceptible to posaconazole. His cutaneous lesion remained stable, but he died from respiratory failure secondary to lobar pneumonia. At lung autopsy, A. rosae was not identified in the lungs. We believe this to be the first published report, to our knowledge, of A. rosae infection in humans.


Assuntos
Alternaria/patogenicidade , Alternariose/microbiologia , Antifúngicos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Feoifomicose/microbiologia , Mielofibrose Primária/terapia , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/terapia , Aciclovir/uso terapêutico , Idoso , Alternaria/isolamento & purificação , Antibioticoprofilaxia/métodos , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Evolução Fatal , Doença Enxerto-Hospedeiro/tratamento farmacológico , Mãos/diagnóstico por imagem , Humanos , Terapia de Imunossupressão/efeitos adversos , Terapia de Imunossupressão/métodos , Levofloxacino/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Testes de Sensibilidade Microbiana , Seios Paranasais/diagnóstico por imagem , Pneumonia/complicações , Prednisona/uso terapêutico , Insuficiência Respiratória/complicações , Esporos Fúngicos/isolamento & purificação , Esporos Fúngicos/patogenicidade , Transplante Homólogo/efeitos adversos , Triazóis/uso terapêutico , Voriconazol/uso terapêutico
13.
Fungal Biol ; 121(2): 172-188, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28089048

RESUMO

Alternaria species, primarily the small-spored Alternaria alternata and the large-spored Alternaria solani, are considered a serious threat to potato cultivation. To develop control strategies, it is important to gain insight into the Alternaria population. Based on the sequence analyses of the internal transcribed spacer region (ITS) and the glyceraldehyde-3-phosphate dehydrogenase gene, the small-spored and large-spored Alternaria isolates could be separated from each other. Sequence analyses of the calmodulin gene and the RNA polymerase second largest subunit showed that besides A. solani also A. grandis and A. protenta were present in the large-spored Alternaria population. Sequence analyses of the Alternaria major allergen gene Alt a 1 and the elongation factor-α revealed that both A. alternata and species belonging to the Alternaria arborescens species complex were present in the small-spored Alternaria population. Furthermore, according to the histone h3 sequence the members of the A. arborescens species complex could be subdivided into two groups. Concerning the fitness, it was concluded that the mycelium growth rate of the large-spored isolates was significantly lower compared to the growth rate of the small-spored isolates. In contrast, the spore-germinating capacity and early growth of the large-spored isolates was greater compared to those of the small-spored isolates. Within the groups of small-spored and large-spored isolates there were no significant differences in fitness between the species.


Assuntos
Alternaria/classificação , Alternaria/isolamento & purificação , Solanum tuberosum/microbiologia , Alternaria/genética , Alternaria/crescimento & desenvolvimento , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Europa (Continente) , Proteínas Fúngicas/genética , Micélio/crescimento & desenvolvimento , Filogenia , Análise de Sequência de DNA , Esporos Fúngicos/crescimento & desenvolvimento
14.
J AOAC Int ; 100(1): 99-103, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27760588

RESUMO

Fungi of the Alternaria genus are associated with allergic diseases, with Alternaria alternata being one of the most prevalent species. A. alternata has been frequently reported as the etiologic agent of hypersensitivity pneumonitis, allergic rhinosinusitis, bronchial asthma, and other diseases. In this study, we developed a loop-mediated isothermal amplification (LAMP) assay and a real-time PCR assay to detect low levels of A. alternata in herbal tea samples. The LAMP assay can detect as little as 3 pg/µL of A. alternata genomic DNA with high specificity. In addition, both the LAMP assay and the real-time PCR assay can be used for quantification of A. alternata. Although the newly developed LAMP assay is more rapid and specific in A. alternata identification, the real-time PCR assay is more precise in quantitation analysis.


Assuntos
Alternaria/isolamento & purificação , Contaminação de Alimentos/análise , Microbiologia de Alimentos/métodos , Técnicas de Amplificação de Ácido Nucleico , Chás de Ervas/microbiologia , Primers do DNA , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade
15.
Nat Prod Res ; 30(20): 2305-10, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27050742

RESUMO

Fungus Alternaria brassicae 93 isolated from crinoid (Comanthina schlegeli), which was collected from the South China Sea. Six compounds were isolated from A. brassicae 93, including one new compound (1), along with five known compounds, ochratoxin A methyl ester (2), cis-4-hydroxym-ellein (3), (R)-7-hydroxymellein (4), trans-2-anhydromevalonic (5) and protocatechuic acid (6). Their structures were determined by spectroscopic methods and comparison with reported data. Cytotoxicity against two human cancer cell lines and antibacterial activity against twelve aquatic bacteria of compound 1 were also tested.


Assuntos
Alternaria/metabolismo , Antibacterianos/farmacologia , Metabolismo Secundário , Alternaria/química , Alternaria/isolamento & purificação , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Hidroxibenzoatos/isolamento & purificação , Hidroxibenzoatos/metabolismo , Hidroxibenzoatos/farmacologia , Isocumarinas/isolamento & purificação , Isocumarinas/metabolismo , Espectroscopia de Ressonância Magnética , Ácido Mevalônico/análogos & derivados , Ácido Mevalônico/isolamento & purificação , Ácido Mevalônico/metabolismo , Estrutura Molecular , Oceanos e Mares , Ocratoxinas/isolamento & purificação , Ocratoxinas/metabolismo , Microbiologia da Água
16.
Prep Biochem Biotechnol ; 44(8): 782-94, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24279735

RESUMO

Tartary buckwheat (Fagopyrum tataricum) is a potentially important source of rutin, a natural bioactive flavonoid with antihyperglycemic, antioxidative, antihypertensive, and anti-inflammatory properties. This study examines the effects of endophytic fungi on rutin production in the hairy root cultures of F. tataricum. Without obvious changes in the appearance of the hairy roots, the exogenous fungal mycelia elicitors efficiently stimulated the hairy root growth and rutin biosynthesis, and the stimulation effect was mainly dependent on the mycelia elicitor species, as well as its treatment dose. Two endophytic fungal isolates Fat9 (Fusarium oxysporum) and Fat15 (Alternaria sp.) were screened as promising candidates for promoting F. tataricum hairy root growth and rutin production. With application of polysaccharide (PS) of endophyte Fat9 (200 mg/L), and PS of endophyte Fat15 (100 mg/L) to the hairy root cultures on day 25, the rutin yield was increased to 45.9 mg/L and 47.2 mg/L, respectively. That was about 3.1- to 3.2-fold in comparison with the control level of 14.6 mg/L. Moreover, the present study revealed that the accumulation of rutin resulted from the stimulation of the phenylpropanoid pathway by mycelia PS treatments. This may be an efficient strategy for enhancing rutin production in F. tataricum hairy root culture provided with its endophytic mycelia elicitors.


Assuntos
Alternaria/fisiologia , Fagopyrum/microbiologia , Fagopyrum/fisiologia , Fusarium/fisiologia , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Rutina/metabolismo , Alternaria/isolamento & purificação , Endófitos/isolamento & purificação , Endófitos/fisiologia , Fusarium/isolamento & purificação , Micélio/isolamento & purificação , Micélio/fisiologia , Polissacarídeos/metabolismo
17.
Phytomedicine ; 20(10): 918-22, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23639188

RESUMO

Endophytic fungi are known as a prolific source for the discovery of structurally interesting and biologically active secondary metabolites, some of which are promising candidates for drug development. In the present study, three anthranoids were isolated from an Alternaria sp. endophytic fungus and evaluated for their antiangiogenic activity in a rat aortic sprouting assay, an ex vivo model of angiogenesis. Of these three compounds, altersolanol (2) was further characterized and found to show a promising activity in ex vivo, in vitro and in vivo angiogenesis asssays. Using human umbilical vein endothelial cells as an in vitro model, the angiogenic effect of 2 was found to occur via suppression of all three main functions of endothelial cells, namely proliferation, tube formation and migration.


Assuntos
Alternaria/química , Inibidores da Angiogênese/isolamento & purificação , Antraquinonas/isolamento & purificação , Endófitos/química , Erythrina/microbiologia , Alternaria/isolamento & purificação , Animais , Antraquinonas/farmacologia , Endófitos/isolamento & purificação , Células Endoteliais da Veia Umbilical Humana , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica/efeitos dos fármacos , Plantas Medicinais/microbiologia , Ratos , Ratos Wistar
18.
J Sci Food Agric ; 93(9): 2315-22, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23423943

RESUMO

BACKGROUND: Since tomato is an important food component, it is imperative to enhance its yield against the activities of many devastating fungal pathogens such as Alternaria alternata. The exploitation of plant innate resistance by cultivation of resistant varieties is an effective measure in this regard. In the present study, 28 tomato varieties were tested against 32 A. alternata isolates, and representative varieties were further evaluated to determine the extent and basis of their antifungal resistance. RESULTS: A significant increase (104.7%) in polyphenols was recorded in the resistant variety Dinaar compared with the susceptible variety Red Tara. Dinaar also exhibited 100% enhancement of alkaloids and terpenoids along with a 30.7% increase in cell wall hemicellulose content. Significant differences were found in physical barriers (cellulose, lignin and pectin) of the representative varieties when stained tissue sections were subjected to colorimetric analysis. Similarly, polyphenol oxidase, peroxidase and phenylalanine ammonia lyase showed increases of 78.37, 114.67 and 125.11% respectively in the resistant variety. Higher expression of glucanase genes was evident from native gel analysis, in which not only the number of isozymes but also the quantity of individual isozymes was significantly increased. CONCLUSION: The resistant variety Dinaar had strong antifungal resistance and can therefore be recommended as suitable for cultivation in the agricultural system of Pakistan.


Assuntos
Alternaria/crescimento & desenvolvimento , Resistência à Doença , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Solanum lycopersicum/microbiologia , Alcaloides/biossíntese , Alternaria/isolamento & purificação , Alternaria/patogenicidade , Catecol Oxidase/biossíntese , Celulose/biossíntese , Celulose/química , Solanum lycopersicum/citologia , Solanum lycopersicum/metabolismo , Paquistão , Pectinas/biossíntese , Peroxidases/biossíntese , Fenilalanina Amônia-Liase/biossíntese , Folhas de Planta/citologia , Folhas de Planta/metabolismo , Proteínas de Plantas/biossíntese , Polifenóis/biossíntese , Especificidade da Espécie , Terpenos/metabolismo , Virulência
19.
J Microbiol ; 51(6): 821-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24385360

RESUMO

In this study, a tropical endophytic fungus, Alternaria alternata Tche-153 was isolated from a Thai medicinal plant Terminalia chebula Rezt. The ethyl acetate extract prepared from the fermentation broth exhibited significant ketoconazole-synergistic activity against Candida albicans. Bioassay-directed fractionation of the ethyl acetate extract led to the isolation of altenusin (1), isoochracinic acid (2), and altenuic acid (3) together with 2,5-dimethyl-7-hydroxychromone (4). Using the disc diffusion method and the microdilution chequerboard technique, only altenusin (1) in combination with each of three azole drugs, ketoconazole, fluconazole or itraconazole at their low sub-inhibitory concentrations exhibited potent synergistic activity against C. albicans with the fractional inhibitory concentration index range of 0.078 to 0.188. This first discovery of altenusin (1) as a new azole-synergistic prototype possessing a biphenyl structure is of significance for further development of new azole-synergists to treat invasive candidiasis.


Assuntos
Alternaria/metabolismo , Antifúngicos/farmacologia , Azóis/farmacologia , Compostos de Bifenilo/farmacologia , Candida/efeitos dos fármacos , Endófitos/metabolismo , Terminalia/microbiologia , Alternaria/química , Alternaria/genética , Alternaria/isolamento & purificação , Antifúngicos/química , Antifúngicos/metabolismo , Compostos de Bifenilo/química , Compostos de Bifenilo/metabolismo , Sinergismo Farmacológico , Endófitos/química , Endófitos/genética , Endófitos/isolamento & purificação , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Estrutura Molecular , Filogenia
20.
Rev. bras. plantas med ; Rev. bras. plantas med;14(spe): 175-182, 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-648544

RESUMO

A incidência de fungos em sementes interfere negativamente o seu potencial fisiológico, podendo ter início no campo, durante o armazenamento ou na pós-colheita. Desta forma o objetivo deste trabalho foi avaliar a qualidade fisiológica e sanitária de sementes de erva-doce armazenadas em diferentes embalagens. O trabalho foi realizado no Laboratório de análise de sementes da UFPB, em Areia-PB. As sementes foram colhidas em plantas tratadas e não tratadas com inseticida Actara, beneficiadas e acondicionadas nas embalagens papel alumínio, saco plástico e vidro. Em seguida, armazenadas em câmara fria durante 315 dias. Inicialmente e a cada 45 dias foram realizados as seguintes determinações e testes: teor de água, emergência de plântulas, primeira contagem de emergência, índice de velocidade de emergência, comprimento e massa seca das plântulas e sanidade das sementes pelo método "blotter-test". Utilizou-se o delineamento inteiramente casualizado, com quatro repetições, os tratamentos foram distribuídos em fatorial 2 x 3 x 8 (com e sem inseticida, 3 embalagens e 8 períodos de avaliação). Os resultados indicam que a qualidade fisiológica das sementes de erva-doce foi principalmente afetada pelo fungo Alternaria sp., ocorrendo a manutenção da viabilidade das sementes por aproximadamente 95 dias na embalagem de saco plástico; a aplicação do inseticida Actara mantém a qualidade fisiológica das sementes de Foeniculum vulgare no armazenamento.


The fungi incidence in seeds affect negatively their physiological potential may begin in the field, during storage or in post-harvest. The objective was to evaluate the sanitary quality of fennel seeds stored in packagings differents. The study was conducted in laboratory analysis of seeds of UFPB, in Areia-PB. Seeds were harvested in experimental field with plants treated and untreated with insecticide Actara, processed and packed in aluminum foil, plastic bag and glass and stored in cold chamber during 315 days. Initially and every 45 days were performed the following tests and determinations: water content, seedling emergence, first count of emergency, emergency speed index, length and seedling dry mass and seed health by the "blotter-test." We used a completely randomized design with four replications, the treatments were distributed in a factorial 2 x 3 x 8. The results indicated that the physiological quality of fennel seeds was negatively affected by the fungus Alternaria sp., occurring at maintaining the viability of seeds for about 95 days in the plastic bag packaging; the application of the insecticide Actara keeps the physiological quality of seeds of Foeniculum vulgare in storage.


Assuntos
Pimpinella/fisiologia , Alternaria/isolamento & purificação , Sementes/fisiologia , Análise de Variância , Proteínas de Armazenamento de Sementes
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