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1.
Mycologia ; 114(1): 175-189, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35073226

RESUMEN

Wulingshen, massive Xylaria sclerotia, was originally reported from Chengdu Plain in western Sichuan of China for medicinal application. Xylaria nigripes is commonly connected to these massive sclerotia produced within abandoned underground macrotermitine termite nests. We sequenced 54 Wulingshen samples procured from traditional Chinese medicine markets in Chengdu Plain and connected them to six different Xylaria species: X. nigripes, X. subescharoidea, two species newly described herein-X. neonigripes and X. rogersionigripes, and two species that are known only as sclerotia thus far. Only teleomorphs of X. subescharoidea and X. rogersionigripes have been collected in Chengdu Plain thus far. In Taiwan, teleomorphs of four of the six species, except for the two only known in sclerotial form, have been collected, and their cultures were obtained; we thus designate the holotypes of X. neonigripes and X. rogersionigripes on the basis of Taiwan specimens. During the collecting activities carried out in Chengdu Plain, a Xylaria species, which is newly described as X. mianyangensis herein, was also collected from termite nests but lacks a known connection to Wulingshen.


Asunto(s)
Isópteros , Xylariales , Animales , Secuencia de Bases , Medicina Tradicional China , Taiwán , Xylariales/genética
2.
Chin J Nat Med ; 17(5): 387-393, 2019 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-31171274

RESUMEN

Replacement of the native promoter of theglobal regulator LaeA-like gene of Daldinia eschscholzii by a strong gpdA promoter led to the generation of two novel cyclopentenone metabolites, named dalestones A and B, whose structures were assigned by a combination of spectroscopic analysis, modified Mosher's reaction, and electronic circular dichroism (ECD). Dalestones A and B inhibit the gene expression of TNF-α and IL-6 in LPS-induced RAW264.7 macrophages.


Asunto(s)
Antiinflamatorios/farmacología , Ciclopentanos/farmacología , Proteínas Fúngicas/genética , Regiones Promotoras Genéticas/genética , Factores de Transcripción/genética , Xylariales/química , Animales , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/metabolismo , Ciclopentanos/química , Ciclopentanos/aislamiento & purificación , Ciclopentanos/metabolismo , Proteínas Fúngicas/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Estructura Molecular , Células RAW 264.7 , Factores de Transcripción/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Xylariales/genética , Xylariales/metabolismo
3.
J Agric Food Chem ; 67(10): 2877-2885, 2019 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-30785752

RESUMEN

Fusarium solani H915 (MCCC3A00957), a fungus originating from mangrove sediment, showed potent inhibitory activity against tea pathogenic fungus Pestalotiopsis theae. Successive chromatographic separation on an ethyl acetate (EtOAc) extract of F. solani H915 resulted in the isolation of five new alkenoic diacid derivatives: fusarilactones A-C (1-3), and fusaridioic acids B (4) and C (5), in addition to seven known compounds (6-12). The chemical structures of these metabolites were elucidated on the basis of UV, IR, HR-ESI-MS, and NMR spectroscopic data. The antifungal activity of the isolated compounds was evaluated. Compounds with a ß-lactone ring (1, 2, and 7) exhibited potent inhibitory activities, while none of the other compounds show activity. The ED50 values of the compounds 1, 2, and 7 were 38.14 ± 1.67, 42.26 ± 1.96, and 18.35 ± 1.27 µg/mL, respectively. In addition, inhibitory activity of these compounds against 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) synthase gene expression was also detected using real-time RT-PCR. Results indicated that compounds 1, 2, and 7 may inhibit the growth of P. theae by interfering with the biosynthesis of ergosterol by down-regulating the expression of HMG-CoA synthase.


Asunto(s)
Camellia sinensis/microbiología , Fungicidas Industriales/farmacología , Fusarium/química , Lactonas/farmacología , Enfermedades de las Plantas/microbiología , Agua de Mar/microbiología , Fungicidas Industriales/química , Fungicidas Industriales/aislamiento & purificación , Fungicidas Industriales/metabolismo , Fusarium/genética , Fusarium/aislamiento & purificación , Fusarium/metabolismo , Lactonas/química , Lactonas/aislamiento & purificación , Lactonas/metabolismo , Estructura Molecular , Xylariales/efectos de los fármacos , Xylariales/genética , Xylariales/crecimiento & desarrollo
4.
Braz. j. microbiol ; 49(4): 840-847, Oct.-Dec. 2018. graf
Artículo en Inglés | LILACS | ID: biblio-974284

RESUMEN

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


Asunto(s)
Enfermedades de las Plantas/prevención & control , Xylariales/química , Paullinia/microbiología , Endófitos/química , Fungicidas Industriales/farmacología , Filogenia , Enfermedades de las Plantas/microbiología , Espectrometría de Masas , Xylariales/aislamiento & purificación , Xylariales/genética , Xylariales/metabolismo , Estructura Molecular , Colletotrichum/efectos de los fármacos , Colletotrichum/fisiología , Endófitos/aislamiento & purificación , Endófitos/genética , Endófitos/metabolismo , Fungicidas Industriales/aislamiento & purificación , Fungicidas Industriales/química
5.
Braz J Microbiol ; 49(4): 840-847, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29631892

RESUMEN

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


Asunto(s)
Endófitos/química , Fungicidas Industriales/farmacología , Paullinia/microbiología , Enfermedades de las Plantas/prevención & control , Xylariales/química , Colletotrichum/efectos de los fármacos , Colletotrichum/fisiología , Endófitos/genética , Endófitos/aislamiento & purificación , Endófitos/metabolismo , Fungicidas Industriales/química , Fungicidas Industriales/aislamiento & purificación , Espectrometría de Masas , Estructura Molecular , Filogenia , Enfermedades de las Plantas/microbiología , Xylariales/genética , Xylariales/aislamiento & purificación , Xylariales/metabolismo
6.
Plant Dis ; 102(1): 98-106, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30673469

RESUMEN

Gray blight of tea, caused by several Pestalotiopsis-like species, is one of the most destructive foliar diseases in tea cultivation yet the characteristics of these pathogens have not been confirmed until now. With morphological and multigene phylogenetic analyses, we have identified the gray blight fungi as Pseudopestalotiopsis camelliae-sinensis, Neopestalotiopsis clavispora, and Pestalotiopsis camelliae. Phylogenetic analyses derived from the combined internal transcribed spacer, ß-tubulin, and translation elongation factor 1-α gene regions successfully resolved most of the Pestalotiopsis-like species used in this study with high bootstrap supports and revealed three major clusters representing these three species. Differences in colony appearance and conidia morphology (shape, size, septation, color and length of median cells, and length and number of apical and basal appendages) were consistent with the phylogenetic grouping. Pathogenicity tests validated that all three species isolated from tea leaves were causal agents of gray blight disease on tea plant (Camellia sinensis). This is the first description of the characteristics of the three species Pseudopestalotiopsis camelliae-sinensis, N. clavispora, and Pestalotiopsis camelliae as causal agents of tea gray blight disease in China.


Asunto(s)
Proteínas Bacterianas/análisis , Camellia sinensis/microbiología , Enfermedades de las Plantas/microbiología , ARN Bacteriano/análisis , Xylariales/clasificación , Xylariales/fisiología , China , Filogenia , Análisis de Secuencia de ADN , Xylariales/genética
7.
Int J Med Mushrooms ; 18(3): 253-60, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27481159

RESUMEN

White jelly mushroom, Tremella fuciformis, is a popular edible mushroom with interesting medicinal properties (e.g., immunostimulating, antidiabetic). The formation of T. fuciformis basidiomes is highly dependent on the presence of a specific host fungus, both in nature and for industrial production. This host has traditionally been indicated as "Xianghui" in China, yet which or how many fungal species Xianghui comprises is unclear, with various authorities claiming different species. At present, Annulohypoxilon archeri is generally assumed to be the main Xianghui species, but this has not yet been confirmed experimentally. The implementation of older, premolecular-based research data (i.e., morphological) with present, sequence-based data to solve the identity remains confusing and studies addressing both identification methods in combination are lacking. The unclear identity of Xianghui is a major obstacle for further understanding of the important relationship between the host(s) and T. fuciformis. In this study, we collected a wild specimen of T. fuciformis together with several nearby stroma of Xianghui, cocultivated T. fuciformis with the Xianghui isolates, and observed basidiome formation. Internal transcribed spacer (ITS) sequence analysis showed that all Xianghui spore isolates belonged to the same species and both morphological analysis of sexual stages and ITS ß-tubulin and actin gene sequences of the Xianghui specified it as Annulohypoxylon stygium. The ITS sequences of the newly identified Xianghui further closely matched those of the Xianghui strains used in the mushroom industry, showing that wild and culture spawn Xianghui in China consist of A. stygium. In contrast with previous conclusions, A. stygium, and not A. archeris, seems to be the preferred host of T. fuciformis.


Asunto(s)
Basidiomycota/clasificación , Xylariales/clasificación , Basidiomycota/citología , Basidiomycota/genética , Cuerpos Fructíferos de los Hongos , Filogenia , Análisis de Secuencia de ADN , Xylariales/citología , Xylariales/genética
8.
Curr Microbiol ; 73(2): 280-6, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27155842

RESUMEN

For screening bilobalide (BB)-producing endophytic fungi from medicinal plant Ginkgo biloba, a total of 57 fungal isolates were isolated from the internal stem, root, leaf, and bark of the plant G. biloba. Fermentation processes using BB-producing fungi other than G. biloba may become a novel way to produce BB, which is a terpene trilactones exhibiting neuroprotective effects. In this study, a BB-producing endophytic fungal strain GZUYX13 was isolated from the leaves of G. biloba grown in the campus of Guizhou University, Guiyang city, Guizhou province, China. The strain produced BB when grown in potato dextrose liquid medium. The amount of BB produced by this endophytic fungus was quantified to be 106 µg/L via high-performance liquid chromatography (HPLC), substantially lower than that produced by the host tissue. The fungal BB which was analyzed by thin layer chromatography (TLC) and HPLC was proven to be identical to authentic BB. The strain GZUYX13 was identified as Pestalotiopsis uvicola via morphology and ITS rDNA phylogeny. To the best of our knowledge, this is the first report concerning the isolation and identification of endophytic BB-producing Pestalotiopsis spp. from the host plant, which further proved that endophytic fungi have the potential to produce bioactive compounds.


Asunto(s)
Ciclopentanos/metabolismo , Endófitos/metabolismo , Furanos/metabolismo , Ginkgo biloba/microbiología , Ginkgólidos/metabolismo , Plantas Medicinales/microbiología , Xylariales/metabolismo , Endófitos/clasificación , Endófitos/genética , Endófitos/aislamiento & purificación , Hojas de la Planta/microbiología , Xylariales/clasificación , Xylariales/genética , Xylariales/aislamiento & purificación
9.
Planta Med ; 81(14): 1285-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26227504

RESUMEN

Four novel polyketides, named pestalpolyols A (1), B (2), C (3), and D (4), were isolated from solid fermentation products of Pestalotiopsis sp. cr013. Their structures were elucidated by extensive spectroscopic methods, including 1D and 2D nuclear magnetic resonance and high-resolution electrospray ionization mass spectrometry experiments, and the absolute configuration was confirmed by single-crystal X-ray diffraction analysis using the anomalous scattering of Cu Kα radiation. The inhibitory activities of compounds 1, 2, and 4 against five human tumor lines were tested in vitro, and showed IC50 values 2.3-31.2 µM.


Asunto(s)
Antineoplásicos/farmacología , Policétidos/química , Policétidos/farmacología , Xylariales/química , Antifúngicos/química , Antifúngicos/farmacología , Antineoplásicos/química , Línea Celular Tumoral/efectos de los fármacos , Cristalografía por Rayos X , Evaluación Preclínica de Medicamentos/métodos , Fermentación , Humanos , Concentración 50 Inhibidora , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Xylariales/genética
10.
Microb Biotechnol ; 6(6): 720-30, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23815379

RESUMEN

Large amount of drilling waste associated with the expansion of the Orinoco Oil Belt (OOB), the biggest proven reserve of extra-heavy crude oil (EHCO) worldwide, is usually impregnated with EHCO and highly salinized water-based drilling fluids. Oxidative exoenzymes (OE) of the lignin-degrading enzyme system (LDS) of fungi catalyse the oxidation of a wide range of toxic pollutants. However, very little evidences on fungal degradation or biotransformation of EHCO have been reported, which contain high amounts of asphaltenes and its biodegradation rate is very limited. The aims of this work were to study the ability of Pestalotiopsis palmarum BM-04 to synthesize OE, its potential to biotransform EHCO and to survive in extreme environmental conditions. Enzymatic studies of the LDS showed the ability of this fungus to overproduce high amounts of laccase (LACp) in presence of wheat bran or lignin peroxidase (LIPp) with EHCO as sole carbon and energy source (1300 U mgP(-1) in both cases). FT-IR spectroscopy with Attenuated Total Reflectance (ATR) analysis showed the enzymatic oxidation of carbon and sulfur atoms in both maltenes and asphaltenes fractions of biotreated EHCO catalysed by cell-free laccase-enriched OE using wheat bran as inducer. UV-visible spectrophotometry analysis revealed the oxidation of the petroporphyrins in the asphaltenes fraction of biotreated EHCO. Tolerance assays showed the ability of this fungus to grow up to 50,000 p.p.m. of EHCO and 2000 mM of NaCl. These results suggest that P. palmarum BM-04 is a hopeful alternative to be used in remediation processes in extreme environmental conditions of salinity and EHCO contamination, such as the drilling waste from the OOB.


Asunto(s)
Proteínas Fúngicas/metabolismo , Lacasa/metabolismo , Petróleo/metabolismo , Xylariales/enzimología , Biodegradación Ambiental , Biotransformación , Proteínas Fúngicas/genética , Residuos Industriales/análisis , Lacasa/genética , Oxidación-Reducción , Petróleo/análisis , Petróleo/microbiología , Xylariales/genética , Xylariales/crecimiento & desarrollo , Xylariales/metabolismo
11.
PLoS One ; 7(10): e46687, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23056404

RESUMEN

BACKGROUND: Nodulisporic acids (NAs) are indole diterpene fungal metabolites exhibiting potent systemic efficacy against blood-feeding arthropods, e.g., bedbugs, fleas and ticks, via binding to arthropod specific glutamate-gated chloride channels. Intensive medicinal chemistry efforts employing a nodulisporic acid A template have led to the development of N-tert-butyl nodulisporamide as a product candidate for a once monthly treatment of fleas and ticks on companion animals. The source of the NAs is a monophyletic lineage of asexual endophytic fungal strains that is widely distributed in the tropics, tentatively identified as a Nodulisporium species and hypothesized to be the asexual state of a Hypoxylon species. METHODS AND RESULTS: Inferences from GenBank sequences indicated that multiple researchers have encountered similar Nodulisporium endophytes in tropical plants and in air samples. Ascomata-derived cultures from a wood-inhabiting fungus, from Martinique and closely resembling Hypoxylon investiens, belonged to the same monophyletic clade as the NAs-producing endophytes. The hypothesis that the Martinique Hypoxylon collections were the sexual state of the NAs-producing endophytes was tested by mass spectrometric analysis of NAs, multi-gene phylogenetic analysis, and phenotypic comparisons of the conidial states. We established that the Martinique Hypoxylon strains produced an ample spectrum of NAs and were conspecific with the pantropical Nodulisporium endophytes, yet were distinct from H. investiens. A new species, H. pulicicidum, is proposed to accommodate this widespread organism. CONCLUSIONS AND SIGNIFICANCE: Knowledge of the life cycle of H. pulicicidum will facilitate an understanding of the role of insecticidal compounds produced by the fungus, the significance of its infections in living plants and how it colonizes dead wood. The case of H. pulicicidum exemplifies how life cycle studies can consolidate disparate observations of a fungal organism, whether from environmental sequences, vegetative mycelia or field specimens, resulting in holistic species concepts critical to the assessment of the dimensions of fungal diversity.


Asunto(s)
Endófitos/metabolismo , Alcaloides Indólicos/metabolismo , Insecticidas/metabolismo , Xylariales/metabolismo , ADN de Hongos/genética , Endófitos/clasificación , Endófitos/genética , Estructura Molecular , Filogenia , Xylariales/clasificación , Xylariales/genética
12.
Curr Genet ; 26(2): 184-6, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8001175

RESUMEN

The Podospora anserina nuclear mutant grisea displays an undifferentiated growth phenotype (diminished production of aerial hyphae), is female sterile (lack of perithecia), has a prolonged life-span compared to the wild-type strain, and lacks detectable phenoloxidase (laccase and tyrosinase) activity. Reversion of all of these characteristics to those of the wild-type phenotype was accomplished by supplementing the growth medium with extra amounts of copper salts. These results indicate that the primary defect of the grisea strain is in its copper uptake and/or distribution in the cells.


Asunto(s)
Cobre/farmacología , Xylariales/genética , Núcleo Celular/metabolismo , Sulfato de Cobre , Relación Dosis-Respuesta a Droga , Lacasa , Mutación , Oxidorreductasas/metabolismo , Fenotipo , Especificidad de la Especie , Xylariales/efectos de los fármacos , Xylariales/crecimiento & desarrollo
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