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1.
J Appl Microbiol ; 135(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38373804

RESUMO

AIM: An extensive survey was done to clarify the prevalent Stemphylium species on Solanaceae plants across Brazil, and their host ranges. METHODS AND RESULTS: Eighty nine (89) Stemphylium isolates were obtained from naturally infected tomatoes as well as S. paniculatum, potato, eggplant, scarlet eggplant (Solanum aethiopicum var. gilo), Physalis angulata, and Capsicum species. Phylogenetic analyses encompassing the ITS-5.8S rDNA and glyceraldehyde-3-phosphate dehydrogenase genomic regions placed the isolates into two distinct groupings with either Stemphylium lycopersici or S. solani. Isolates of S. lycopersici (n = 81) were obtained infecting tomato, potato, eggplant, S. paniculatum, and P. angulata. Isolates of S. solani (n = 8) were detected in natural association with scarlet eggplant and tomato. Two isolates of S. lycopersici displayed a wide experimental host range in greenhouse bioassays, infecting accessions of 12 out of 18 species. Ocimum basilicum (Lamiaceae) was the only experimental host outside the Solanaceae family.


Assuntos
Capsicum , Fungos Mitospóricos , Solanum lycopersicum , Solanum tuberosum , Brasil , Filogenia , Verduras
2.
Pest Manag Sci ; 80(1): 92-102, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37794581

RESUMO

Among the alternatives to synthetic plant protection products, biocontrol appears as a promising method. This review reports on the diversity of fungal secondary metabolites phytotoxic to weeds and on the approach generally used to extract, characterize, identify and exploit them for weed management. The 183 phytotoxic fungal secondary metabolites discussed in this review fall into five main classes of molecules: 61 polyketides, 53 terpenoids, 36 nitrogenous metabolites, 18 phenols and phenolic acids, and 15 miscellaneous. They are mainly produced by the genera Drechslera, Fusarium and Alternaria. The phytotoxic effects, more often described by the symptoms they produce on plants than by their mode of action, range from inhibition of germination to inhibition of root and vegetative growth, including tissue and organ alterations. The biochemical characterization of fungal secondary metabolites requires expertise and tools to carry out fungal cultivation and metabolite extraction, phytotoxicity tests, purification and fractionation of the extracts, and chemical identification procedures. Phytotoxicity tests are mainly carried out under controlled laboratory conditions (not always on whole plants), while effectiveness against targeted weeds and environmental impacts must be assessed in greenhouses and open fields. These steps are necessary for the formulation of effective, environment-friendly fungal secondary metabolites-derived bioherbicides using new technologies such as nanomaterials. © 2023 Society of Chemical Industry.


Assuntos
Alcaloides , Herbicidas , Fungos Mitospóricos , Herbicidas/química , Plantas Daninhas , Alcaloides/farmacologia , Extratos Vegetais/farmacologia
3.
Sci Rep ; 13(1): 22795, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129458

RESUMO

The fungal genus Rachicladosporium (Cladosporiales, Cladosporiaceae), typified by cladosporium-like Rachicladosporium luculiae, includes a morphologically diverse assemblage of species. The species of this genus were reported from different substrates, habitats and environments, including plant leaves and needles, twig, black mould on baobab trees, rocks and insects. In this study, four new Rachicladosporium species (R. europaeum, R. ignacyi, R. kajetanii, R. silesianum) isolated from sooty mould communities covering leaves and needles of trees and shrubs in Poland are described. The new species are delineated based on morphological characteristics and molecular phylogenetic analyses using concatenated ITS, LSU, and rpb2 sequences. All newly described species are nested in the main Rachicladosporium lineage (centred around the type species), which contains species that are able to grow at 25 °C. By contrast, four cold adapted, endolithic species known from Antarctica (R. antarcticum, R. aridum, R. mcmurdoi) and Italian Alps (R. monterosanum) form distant phylogenetic lineage and do not grow at this temperature. Therefore, they are accommodated in the new genus Cryoendolithus, typified by Cryoendolithus mcmurdoi.


Assuntos
Fungos Mitospóricos , Animais , Filogenia , Insetos , Ecossistema , Polônia
4.
BMC Microbiol ; 23(1): 163, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37280536

RESUMO

In the current study, fifty-eight Ingoldain fungal species assignable to forty-one genera were recovered from two water bodies receiving the treated sewage and the effluents of oils and soaps factory at Assiut Governorate (Upper Egypt), of which Anguillospora, Amniculicola, Flagellospora, and Mycocentrospora were the most prevalent genera. The most widespread identified species were Anguillospora furtive, Amniculicola longissima and Flagellospora fusarioides. Forty-three species were identified for the first time in Egypt. The most Ingoldain taxa were estimated for El-Zinnar canal, with the highest recorded taxa in winter. Whereas, the highest dominance of Ingoldian fungi was estimated for the El-Ibrahimia canal. The highest Simpson and Shannon diversity indexes were estimated for El-Zinnar canal samples recording 0.9683 and 3.741, respectively. The poorest water sites with Ingoldian fungi were those exposed directly to either treated sewage or industrial effluents, with which relatively higher values of water conductivity, cations and anions. Water temperature was the main abiotic factor driving the seasonal occurrence of Ingoldian fungi. It is interesting to isolate some Ingoldian fungal species from the stressful water sites receiving the effluents which provide valuable insights regarding their adaptation, predictive and putative role as bioindicators and their potentiality in pollutants degradation, organic decomposition, and transformation of xenobiotic compounds.


Assuntos
Fungos Mitospóricos , Esgotos , Egito , Esgotos/microbiologia , Estações do Ano , Água
5.
J Nat Prod ; 86(6): 1596-1605, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37276438

RESUMO

Xanthoquinodins make up a distinctive class of xanthone-anthraquinone heterodimers reported as secondary metabolites from several fungal species. Through a collaborative multi-institutional screening program, a fungal extract prepared from a Trichocladium sp. was identified that exhibited strong inhibitory effects against several human pathogens (Mycoplasma genitalium, Plasmodium falciparum, Cryptosporidium parvum, and Trichomonas vaginalis). This report focuses on one of the unique samples that exhibited a desirable combination of biological effects: namely, it inhibited all four test pathogens and demonstrated low levels of toxicity toward HepG2 (human liver) cells. Fractionation and purification of the bioactive components and their congeners led to the identification of six new compounds [xanthoquinodins NPDG A1-A5 (1-5) and B1 (6)] as well as several previously reported natural products (7-14). The chemical structures of 1-14 were determined based on interpretation of their 1D and 2D NMR, HRESIMS, and electronic circular dichroism (ECD) data. Biological testing of the purified metabolites revealed that they possessed widely varying levels of inhibitory activity against a panel of human pathogens. Xanthoquinodins A1 (7) and A2 (8) exhibited the most promising broad-spectrum inhibitory effects against M. genitalium (EC50 values: 0.13 and 0.12 µM, respectively), C. parvum (EC50 values: 5.2 and 3.5 µM, respectively), T. vaginalis (EC50 values: 3.9 and 6.8 µM, respectively), and P. falciparum (EC50 values: 0.29 and 0.50 µM, respectively) with no cytotoxicity detected at the highest concentration tested (HepG2 EC50 > 25 µM).


Assuntos
Anti-Infecciosos , Criptosporidiose , Cryptosporidium , Fungos Mitospóricos , Humanos , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Estrutura Molecular
6.
Molecules ; 28(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37110794

RESUMO

This study aimed to assess the markers of chemical and microbiological contamination of the air at sport centers (e.g., the fitness center in Poland) including the determination of particulate matter, CO2, formaldehyde (DustTrak™ DRX Aerosol Monitor; Multi-functional Air Quality Detector), volatile organic compound (VOC) concentration (headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry), the number of microorganisms in the air (culture methods), and microbial biodiversity (high-throughput sequencing on the Illumina platform). Additionally the number of microorganisms and the presence of SARS-CoV-2 (PCR) on the surfaces was determined. Total particle concentration varied between 0.0445 mg m-3 and 0.0841 mg m-3 with the dominance (99.65-99.99%) of the PM2.5 fraction. The CO2 concentration ranged from 800 ppm to 2198 ppm, while the formaldehyde concentration was from 0.005 mg/m3 to 0.049 mg m-3. A total of 84 VOCs were identified in the air collected from the gym. Phenol, D-limonene, toluene, and 2-ethyl-1-hexanol dominated in the air at the tested facilities. The average daily number of bacteria was 7.17 × 102 CFU m-3-1.68 × 103 CFU m-3, while the number of fungi was 3.03 × 103 CFU m-3-7.34 × 103 CFU m-3. In total, 422 genera of bacteria and 408 genera of fungi representing 21 and 11 phyla, respectively, were detected in the gym. The most abundant bacteria and fungi (>1%) that belonged to the second and third groups of health hazards were: Escherichia-Shigella, Corynebacterium, Bacillus, Staphylococcus, Cladosporium, Aspergillus, and Penicillium. In addition, other species that may be allergenic (Epicoccum) or infectious (Acinetobacter, Sphingomonas, Sporobolomyces) were present in the air. Moreover, the SARS-CoV-2 virus was detected on surfaces in the gym. The monitoring proposal for the assessment of the air quality at a sport center includes the following markers: total particle concentration with the PM2.5 fraction, CO2 concentration, VOCs (phenol, toluene, and 2-ethyl-1-hexanol), and the number of bacteria and fungi.


Assuntos
Poluição do Ar em Ambientes Fechados , COVID-19 , Fungos Mitospóricos , Exposição Ocupacional , Exposição Ocupacional/análise , Dióxido de Carbono/análise , Microbiologia do Ar , COVID-19/epidemiologia , SARS-CoV-2 , Aerossóis e Gotículas Respiratórios , Fungos , Bactérias , Material Particulado/análise , Fenóis/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental
7.
Mycologia ; 115(3): 357-374, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37001028

RESUMO

Graphium species form a well-supported monophyletic lineage within the Microascales (Ascomycota). Members of this genus can be found in association with bark beetles, as well as on tree wounds and in soils. During surveys of bark and ambrosia beetle-associated fungi and cavities made by woodpeckers on hardwood trees in Poland, many isolates with an affinity to Graphium were recovered. They were identified based on their morphological characters and sequence data for the internal transcribed spacer (ITS), 28S rDNA, ß-tubulin (TUB2), and translation elongation factor 1-α (TEF1) gene regions. The results revealed five new species, described here as G. brachiatum, G. longistipitatum, G. polonicum, G. radicatum, and G. trypophloei.


Assuntos
Ascomicetos , Fungos Mitospóricos , Gorgulhos , Animais , Árvores , Polônia , Filogenia , Gorgulhos/microbiologia
8.
J Appl Microbiol ; 134(2)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36724275

RESUMO

AIMS: To investigate fungal diversity and biosurfactant-producing fungi in four oil-contaminated sites. METHODS AND RESULTS: Water and sediment samples were collected from four sites in Brittany (France), over two periods, in winter/spring and summer. Fungal diversity was investigated using a metagenetic approach targeting the ITS2 region. Surface-active compound production of 701 fungal isolates collected from these samples after direct plating or following enrichment was assessed using oil spreading and Parafilm M tests. Fungal communities were highly diverse and the main dominant fungal taxa were members of the Cladosporium, Penicillium, Pseudeurotium, Phoma, Aspergillus, and Trichoderma as well as Ochroconis, Fusicolla, and Aureobasidium genera in specific sites. A total of 179 isolates (25.5% of total isolates) were positive to at least one of the screening tests, while 105 were positive to both tests. Major genera among the positive isolates were Fusarium, Trichoderma, Candida, and Penicillium. Six isolates belonging to Aureobasidium pullulans, Mucor griseocyanus, Trichoderma citrinoviride, Trichoderma harzianum, Trichodermalongibrachiatum, and Diaporthe eres showed promising activities. CONCLUSIONS: The present study highlighted the fungal diversity of oil-contaminated environments and the fact that surface-active compound production is widespread in fungi originating from these habitats.


Assuntos
Fungos Mitospóricos , Penicillium , Trichoderma , Fungos , Tensoativos , Aspergillus/genética , Candida , Penicillium/genética , Trichoderma/genética
9.
Microb Ecol ; 85(4): 1215-1225, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35415771

RESUMO

Anthropogenic change at a global scale is affecting life on Earth with impacts on freshwaters. Aquatic hyphomycetes are fungi that drive organic matter decomposition in freshwaters and mediate energy transfer to higher trophic levels. Intraspecific trait variability affects ecological processes and can account for species adaptations to environmental change. To ascertain how aquatic hyphomycetes respond to global change related stressors, we selected 20 strains (7 species), based on their co-occurrence in streams and phylogenetic relatedness. We measured fungal growth rates at different temperatures (7 levels), nutrient concentrations (6 levels) and medium moisture (6 levels). Our results indicate that all stressors affected fungal growth, and responses to nutrient enrichment and moisture were strain specific. Fungal responses to the stressors were not explained by their phylogenetic relatedness. In the absence of stressors, interspecific diversity best explained the variance in fungal traits, while the increase in the stress gradient increased the importance of intraspecific diversity.


Assuntos
Fungos Mitospóricos , Filogenia , Fungos Mitospóricos/fisiologia , Rios/microbiologia , Água Doce , Fenótipo , Folhas de Planta/microbiologia , Fungos/genética , Ecossistema
10.
Nat Prod Res ; 37(3): 424-433, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34514928

RESUMO

Mitidjospirone, a new spiridioxynaphthalene, was isolated from the mycelial extract of a strain of Lasiodiplodia mitidjana, a recently described species belonging to the family Botryosphaeriaceae. Its structure was elucidated by extensive spectroscopic analysis and the absolute configuration was determined by electronic circular dichroism (ECD) experiment. Furthermore, several known compounds were identified during the screening of secondary metabolites produced by four strains of L. mitidjana.


Assuntos
Ascomicetos , Citrus sinensis , Fungos Mitospóricos , Cromatografia Gasosa-Espectrometria de Massas , Filogenia , Doenças das Plantas , Ascomicetos/metabolismo
11.
Acta Med Port ; 36(5): 353-357, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35973433

RESUMO

Pithomyces, a dematiaceous fungus, is a common colonizer of dead leaves and stems of many different plants and is associated with facial eczema in some animals. We report a case of invasive fungal pulmonary disease by Pithomyces chartarum in a healthy, nonimmunocompromised patient. We aim to demonstrate our diagnostic and therapeutic approach and focus on the major challenges arising from the lack of scientific evidence regarding infection by this fungus in humans.


Pithomyces, um fungo demáceo, é um colonizador comum de folhas e caules de diferentes plantas e está associado a eczema facial em alguns animais. Neste trabalho, descrevemos um caso de infeção fúngica invasiva pelo fungo Pithomyces chartarum, numa mulher não imunocomprometida. O nosso objetivo é descrever a abordagem diagnóstica e terapêutica deste caso, realçando os principais desafios que surgem devido à falta de evidência científica relativamente à infeção deste fungo em humanos.


Assuntos
Fungos Mitospóricos , Micoses , Neoplasias , Animais , Humanos , Micoses/microbiologia , Aspergillus , Pulmão
12.
An Acad Bras Cienc ; 94(suppl 3): e20210192, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36197358

RESUMO

Aquatic hyphomycetes are fungi with a fundamental ecological role in forested streams. These organisms are responsible for cycling of nutrients in aquatic environments. However, their structure and composition can be affected when exposed to certain pollutants. Arsenic (As) is a trace element with high toxicity for the aquatic biota. Here we evaluated the effects of different concentrations of Arsenite (AsIII) and Arsenate (AsV) on aquatic hyphomycetes assemblages. To test As toxicity, we conditioned Nectandra megapotamica leaves in a stream and after this period, we incubated leaf discs with stream water and different concentrations of AsIII and AsV. Species richness was negatively affected by both As form. Likewise, the hyphomycetes assemblages presented variation in the composition of species. However, the sporulation rates were not influenced by As. The As showed toxicity on species of hyphomycetes more sensitive, remaining only in species tolerant to its toxicity. In this way, As generated a change in the aquatic hyphomycetes composition. We observed that As had a negative effect on the aquatic hyphomycetes assemblages, regardless of the chemical form. Our results point to the toxicity of this element and its effects on a group that is fundamental to the streams ecosystems functioning.


Assuntos
Arsênio , Fungos Mitospóricos , Rios , Poluição Química da Água , Arseniatos/toxicidade , Arsênio/toxicidade , Arsenitos/toxicidade , Ecossistema , Folhas de Planta , Rios/química , Oligoelementos/toxicidade , Poluição Química da Água/efeitos adversos , Poluição Química da Água/análise
13.
Rev. peru. med. exp. salud publica ; 39(3): 321-327, jul.-sep. 2022. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1410009

RESUMO

RESUMEN Objetivo . Analizar y determinar la actividad antifúngica in vitro del extracto etanólico de las hojas de Solanum hispidum Pers. Materiales y métodos . Se realizó el análisis fitoquímico preliminar cualitativo mediante reacciones de color y precipitación. Se investigó la actividad antifúngica in vitro frente a Candida albicans, Aspergillus brasilensis y Trichophyton mentagrophytes usando el método de difusión en pozo de agar y el ensayo de la concentración mínima inhibitoria (CMI). Resultados . El análisis fitoquímico preliminar cualitativo mostró la presencia de compuestos fenólicos, taninos, flavonoides, esteroides, alcaloides y saponinas. La actividad antifúngica in vitro fue demostrada para todos cultivos fúngicos con halos de inhibición entre 23 a 26 mm. Los valores de la CMI fueron de 125, 250 y 125 µg/mL para C. albicans, A. brasilensis y T. mentagrophytes, respectivamente. Conclusiones. El extracto etanólico de las hojas de Solanum hispidum Pers contiene importantes metabolitos secundarios y tiene moderada actividad antifúngica.


ABSTRACT Objective. To analyze and determine the in vitro antifungical activity of the ethanolic extract of the leaves of Solanum hispidum Pers. Materials and methods. We carried out a preliminary qualitative phytochemical analysis by color and precipitation reactions. We evaluated the in vitro antifungical activity against Candida albicans, Aspergillus brasilensis and Trichophyton mentagrophytes by using the agar well diffusion method and the minimum inhibitory concentration (MIC) assay. Results. Preliminary qualitative phytochemical analysis showed the presence of phenolic compounds, tannins, flavonoids, steroids, alkaloids and saponins. In vitro antifungal activity was demonstrated for all fungal cultures with inhibition halos between 23 to 26 mm. The MIC values were 125, 250, and 125 μg/mL for C. albicans, A. brasilensis, and T. mentagrophytes, respectively. Conclusions. The ethanolic extract of the leaves of Solanum hispidum Pers. contains important secondary metabolites and has moderate antifungical activity.


Assuntos
Extratos Vegetais/farmacologia , Folhas de Planta/química , Solanum/química , Fungos Mitospóricos/efeitos dos fármacos , Antifúngicos/farmacologia , Extratos Vegetais/química , Etanol , Compostos Fitoquímicos/análise
14.
Braz J Biol ; 84: e262480, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35830133

RESUMO

Previous domestic and foreign studies have shown the significant effect of Talaromyces flavus on growth inhibition of some important plant pathogens including Verticillium dahliae, Fusarium oxysporum f. sp. lycopersici and Fusarium oxysporum f. sp. cucumerinum. In Iran, it is necessary to produce new formulations of this fungus based on modern technologies given the importance of attracting companies producing biological control agents and transferring the technical knowledge of mass production of formulations of these agents to them. In the present study, based on the method presented in the Pesticide Research Department of the Iranian Plant Protection Research Institute, two types of T. flavus formulations in the form of nano-capsules containing Talaromyces flavus with two forms of powder and suspension were prepared using nanotechnology. In the next step, during the greenhouse examination, the efficiency of each of these new formulations in concentrations of one to five per thousand for soil addition method and concentration of five per thousand for seed impregnation method (six treatments for each of the two new formulations) was compared with the registered formulation of Talaromin in two methods of seed impregnation and soil addition with healthy control and infected control to control cotton Verticillium wilt disease, in the form of a randomized complete block design with 16 treatments and 5 replications. After statistical analysis of the data obtained by Duncan's Multiple Range Test by MS TAT C software, the results showed that in terms of disease severity among treatments with the previous formulation (Talaromin) with each of the methods of soil addition and seed impregnation, there was no statistically significant difference between nano-suspension with each of the concentrations of one, four and five per thousand by the soil addition method and nano-powder with each of the concentrations of two and three per thousand by soil addition method, and the mentioned treatments were included in one statistical group in terms of disease severity with healthy control.


Assuntos
Fungos Mitospóricos , Verticillium , Fusarium , Incidência , Irã (Geográfico) , Doenças das Plantas/prevenção & controle , Pós , Solo , Talaromyces , Verticillium/fisiologia
15.
Environ Pollut ; 310: 119726, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35810983

RESUMO

It is estimated that over 700,000 tons of synthetic dyes are produced annually, 15% of which are emitted as effluents. These highly stable dyes enter the world water ecosystems and stay in the environment, and eventually cause adverse impacts to the environment. Current wastewater treatment methods, such as filtration, coagulation, and chemical oxidation, have sideeffects, including toxic residue formation, membrane fouling, bioaccumulation, and secondary pollutant formation. Given the issues mentioned, it is necessary to study how to improve the degradation of synthetic dye with a cost-effective and ecofriendly approach. Natural oxidation provides a greener option. Recently, Deuteromycetes fungus Myrothecium verrucaria G-1 (M. verrucaria G-1) has shown great potential in producing high level of dye oxidase. This study aims to generate a dye oxidase hyperproducer, 3H6 from M. verrucaria G-1 by using atmospheric and room temperature plasma (ARTP) coupled with ultraviolet (UV) irradiation. This method increases oxidase production by nearly 106.15%. After a simple precipitation and dialysis, this mutant oxidase increases by 1.97-fold in a specific activity with dye degradation rates at 70% for Mmethylene blue (MB) and 85% for Congo red (CR). It is found that the genetic stability of 3H6 remains active for ten generations. The size of oxidase is 65 kDa, and optimum temperature for reaction is 30 °C with 4.5 pH. This study presents that the first combined mutagenesis approach by ARPT-UV on fungus species generates an impressive increment of acid dye oxidases production. As such, this method presents a cost-effective alternative to mitigate hazardous dye pollution.


Assuntos
Hypocreales , Fungos Mitospóricos , Poluentes Químicos da Água , Corantes , Ecossistema , Mutagênese , Oxirredutases
16.
Arch Microbiol ; 204(7): 378, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35678928

RESUMO

During an investigation of freshwater fungi in Jiangxi province, China, a new hyphomycetous fungus, Aquapteridospora jiangxiensis, was collected and isolated. Aquapteridospora jiangxiensis is characterized by its unbranched and guttulate conidiophores with multi-septa swollen at the base, polyblastic conidiogenous cells with sympodial proliferations, and denticles, and guttulate conidia with a sheath. A photo plate of the macro- and micro-morphology and a muti-loci (ITS, LSU, SSU, TEF1 and RPB2) phylogenetic tree are provided. A key to the species of Aquapteridospora is also presented in this paper.


Assuntos
Ascomicetos , Fungos Mitospóricos , DNA Fúngico/genética , DNA Ribossômico , Ecossistema , Água Doce , Filogenia , Análise de Sequência de DNA
17.
Plant Dis ; 106(12): 3050-3060, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35612576

RESUMO

Maize leaf spot occurs worldwide and affects maize production. Maize can be infected by several pathogens causing leaf spot, such as Bipolaris zeicola, Bipolaris maydis, Curvularia species, Alternaria species, etc. In the current study, 30 Epicoccum isolates recovered from symptomatic maize leaves were identified based on morphological characteristics, pathogenicity, and multilocus sequence analyses of nuLSU, ITS, tub2, and rpb2. These maize isolates were grouped into five Epicoccum species, including E. nigrum, E. layuense, E. sorghinum, E. latusicollum, and E. pneumoniae. Pathogenicity tests showed that all five Epicoccum species could produce small ellipse- and spindle-shaped spots on maize leaves. The lesion center was grayish yellow to dark gray and surrounded by a chlorotic area. Furthermore, the Epicoccum isolates exhibited high pathogenicity to 20 main maize varieties of Heilongjiang Province but showed different sensitivities to the commonly used fungicides carbendazim and tebuconazole. In addition, these Epicoccum isolates showed different production capacity of pectinase, cellulase, protease, amylase, laccase, and gelatinase, but all showed high lipase activity. This is the first report globally of E. layuense, E. latusicollum, and E. pneumoniae as causal agents of maize leaf spot. E. pneumoniae was first reported as a plant pathogen.


Assuntos
Ascomicetos , Fungos Mitospóricos , Zea mays , Ascomicetos/genética , Alternaria , China
18.
Int J Mol Sci ; 23(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35408835

RESUMO

The important disease Ramularia leaf spot of barley is caused by the fungus Ramularia collo-cygni. The disease causes yield and quality losses as a result of a decrease in photosynthesis efficiency due to the appearance of necrotic spots on the leaf surface. The development of these typical Ramularia leaf spot symptoms is thought to be linked with the release of phytotoxic secondary metabolites called rubellins in the host. However, to date, neither the biosynthetic pathways leading to the production of these metabolites nor their exact role in disease development are known. Using a combined in silico genetic and biochemistry approach, we interrogated the genome of R. collo-cygni to identify a putative rubellin biosynthetic gene cluster. Here we report the identification of a gene cluster containing homologues of genes involved in the biosynthesis of related anthraquinone metabolites in closely related fungi. A putative pathway to rubellin biosynthesis involving the genes located on the candidate cluster is also proposed.


Assuntos
Ascomicetos , Hordeum , Fungos Mitospóricos , Ascomicetos/genética , Ascomicetos/metabolismo , Hordeum/genética , Hordeum/microbiologia
20.
Mar Drugs ; 20(3)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35323476

RESUMO

An unusual sesquiterpene glycoside trichoacorside A (1) and two novel sorbicillinoid glycosides sorbicillisides A (2) and B (3), together with a known compound sorbicillin (4), were isolated and identified from the culture extract of an endophytic fungus Trichoderma longibrachiatum EN-586, obtained from the marine red alga Laurencia obtusa. Trichoacorside A (1) is the first representative of a glucosamine-coupled acorane-type sesquiterpenoid. Their structures were elucidated based on detailed interpretation of NMR and mass spectroscopic data. The absolute configurations were determined by X-ray crystallographic analysis, chemical derivatization, and DP4+ probability analysis. The antimicrobial activities of compounds 1-4 against several human, aquatic, and plant pathogens were evaluated.


Assuntos
Anti-Infecciosos , Endófitos/química , Glicosídeos , Hypocreales/química , Laurencia/microbiologia , Policetídeos , Resorcinóis , Sesquiterpenos , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Fungos Mitospóricos/efeitos dos fármacos , Fungos Mitospóricos/crescimento & desenvolvimento , Estrutura Molecular , Policetídeos/química , Policetídeos/isolamento & purificação , Policetídeos/farmacologia , Resorcinóis/química , Resorcinóis/isolamento & purificação , Resorcinóis/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia
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