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1.
Mycoses ; 67(5): e13728, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38695201

RESUMEN

BACKGROUND: Fungal keratitis is a severe eye infection that can result in blindness and visual impairment, particularly in developing countries. Fusarium spp. are the primary causative agents of this condition. Diagnosis of Fusarium keratitis (FK) is challenging, and delayed treatment can lead to serious complications. However, there is limited epidemiological data on FK, especially in tropical areas. OBJECTIVES: This study aimed to describe the clinical, laboratorial and epidemiological characteristics of FK in a tropical semi-arid region of Brazil. PATIENTS/METHODS: Adult patients with laboratory-confirmed FK diagnosed between October 2019 and March 2022 were evaluated. Fusarium isolates were characterized at molecular level and evaluated regarding antifungal susceptibility. RESULTS: A total of 226 clinical samples from patients suspected of keratitis were evaluated; fungal growth was detected in 50 samples (22.12%); out of which 42 were suggestive of Fusarium spp. (84%). Molecular analysis of a randomly selected set of 27 isolates identified F. solani species complex (n = 14); F. fujikuroi sensu lato (n = 6) and F. dimerum sensu lato (n = 7); a total of 10 haplotypes were identified among the strains. All but one Fusarium strains were inhibited by amphotericin B, natamycin and fluconazole. Most patients were male (71.42%; 30 out of 42), aged from 27 to 73 years old. Trauma was the most important risk factor for FK (40.47%; 17 out of 42). Patients were treated with antifungals, corticoids and antibiotics; keratoplasty and eye enucleation were also performed. CONCLUSIONS: The study provided insights into the characteristics of FK in tropical regions and emphasized the importance of enhanced surveillance and management strategies.


Asunto(s)
Antifúngicos , Infecciones Fúngicas del Ojo , Fusariosis , Fusarium , Queratitis , Pruebas de Sensibilidad Microbiana , Humanos , Brasil/epidemiología , Fusarium/genética , Fusarium/efectos de los fármacos , Fusarium/aislamiento & purificación , Fusarium/clasificación , Masculino , Femenino , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Adulto , Queratitis/microbiología , Queratitis/epidemiología , Queratitis/tratamiento farmacológico , Persona de Mediana Edad , Fusariosis/microbiología , Fusariosis/epidemiología , Fusariosis/tratamiento farmacológico , Infecciones Fúngicas del Ojo/microbiología , Infecciones Fúngicas del Ojo/epidemiología , Infecciones Fúngicas del Ojo/tratamiento farmacológico , Anciano , Adulto Joven , Adolescente , Clima Tropical , Anciano de 80 o más Años , Anfotericina B/farmacología , Anfotericina B/uso terapéutico
2.
World J Microbiol Biotechnol ; 40(6): 185, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38683236

RESUMEN

Stalk rot disease is a major constraint in maize production and till date reported to be caused by two to three species of phytopathogenic fungi but, in our present study, we disclose the first report of stalk rot is caused by complex species of phytopathogens, which belongs to five different genera. Therefore, to substantiate these findings, a total of 105 diseased samples of maize were collected from 21 different locations in six different geographical locations of India from which 48 isolates were used for the research study. Morphological features such as pigmentation, colony color, type of mycelium and pattern of mycelium was examined using macro and microscopic methods. A total of 11 different spp. of pathogens belonging to the five different genera: Fusarium verticillioides (56.25%), F. equiseti (14.5%), F. andiyazi (6.25%), F. solani (2.08%), F. proliferatum (2.08%), F. incarnatum (2.08%), Lasidioplodia theobrame (6.25%), Exserohilum rostrtum (4.16%), Nigrospora spp. (4.16%). and Schizophyllum commune (2.08%) were identified by different housekeeping genes (ITS, TEF-1α, RPB2 and Actin). Fusarium verticillioides, F. equiseti and F. andiyazi were major pathogens involved in stalk rot. This is the first report on F. proliferatum, F. solani, F. incarnatum, Lasidioplodia theobrame, Exserohilum rostrtum, Nigrospora spp. and Schizophyllum commune causing stalk rot of maize and their distribution in the different states of India. Studies on population dynamics of PFSR will enhance the understanding of pathogen behavior, virulence, or its association with different pathogens across India, which will facilitate the development of resistant maize genotypes against the PFSR.


Asunto(s)
Fusarium , Filogenia , Enfermedades de las Plantas , Zea mays , Zea mays/microbiología , Enfermedades de las Plantas/microbiología , India , Fusarium/genética , Fusarium/clasificación , Fusarium/aislamiento & purificación , Fusarium/patogenicidad , ADN de Hongos/genética , Hongos/genética , Hongos/clasificación , Hongos/aislamiento & purificación , Hongos/patogenicidad , Variación Genética
3.
World J Microbiol Biotechnol ; 40(6): 175, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647735

RESUMEN

The demand for environment-friendly cleanup techniques has arisen due to an increase in environmental pollutants. Fungi is the most prevalent and effective class of heavy metal-resistant microorganisms with the ability to leach metals. The objective of the present study was to isolate the fungi from the agricultural soil of Kashmir valley, investigate their multi-metal tolerance to heavy metals and evaluate the metal uptake capacities of the resistant fungi. The fungi were isolated and identified on the basis of morphological and molecular approach (ITS1 and ITS4). The tolerance limits of the isolated fungal strains to various doses of lead (Pb), cadmium (Cd), zinc (Zn), chromium (Cr), copper (Cu), nickel (Ni), and cobalt (Co) was evaluated. Five fungal strains, Aspergillus niger, Fusarium oxysporum, Fusarium verticillioides, Aspergillus fischeri, Epicoccum mackenziei were isolated from the soil samples. To the best of our knowledge, this is the first report on the study of metal resistance of Aspergillus fischeri and Epicoccum mackenziei. Among the identified fungal species, Aspergillus niger and Fusarium oxysporum were found to be most tolerant with a minimum inhibitory concentration (MIC) of 600 ppm against Cu and Cr respectively. Results indicated removal of considerable amount of heavy metals by some of the fungi. The highest metal uptake of 8.31 mg/g was found in Fusarium verticillioides for Zn. Surprisingly, these fungal strains demonstrated resistance to metal concentrations above the levels that are universally acceptable for polluted soils, and hence prove to be appealing contenders for use as bioremediation agents for cleaning up heavy metal-polluted environments.


Asunto(s)
Hongos , Fusarium , Metales Pesados , Pruebas de Sensibilidad Microbiana , Microbiología del Suelo , Contaminantes del Suelo , Metales Pesados/metabolismo , Contaminantes del Suelo/metabolismo , Hongos/efectos de los fármacos , Hongos/aislamiento & purificación , Hongos/clasificación , Hongos/metabolismo , Fusarium/aislamiento & purificación , Fusarium/efectos de los fármacos , Fusarium/metabolismo , Biodegradación Ambiental , Aspergillus niger/aislamiento & purificación , Aspergillus niger/efectos de los fármacos , Aspergillus niger/metabolismo , Suelo/química , Aspergillus/efectos de los fármacos , Aspergillus/metabolismo , Aspergillus/aislamiento & purificación
4.
Int J Food Microbiol ; 417: 110715, 2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38657420

RESUMEN

Head blight (HB) of oat (Avena sativa) has caused significant production losses in oats growing areas of western China. A total of 314 isolates, associated with HB were collected from the major oat cultivating areas of Gansu, Qinghai, and Yunnan Provinces in western China. Based on morphological characters, the isolates were initially classified into three genera, as differentiation to species was a bit difficult. Taxonomic analysis of these isolates based on muti-gene phylogenetic analyses (ITS, TEF1, TUB2, and RPB2) revealed four known Fusarium species, F. proliferatum, F. avenaceum, F. poae, and F. sibiricum, and one Acremonium specie (A. sclerotigenum). In addition, a new genus Neonalanthamala gen. nov., similar to genus Nalanthamala was introduced herein with a new combination, Neonalanthamala graminearum sp. nov., to accommodate the HB fungus. The molecular clock analyses estimated the divergence time of the Neonalanthamala and Nalanthamala based on a dataset (ITS, TUB2, RPB2), and we recognized the mean stem ages of the two genera are 98.95 Mya, which showed that they evolved from the same ancestor. N. graminearum was the most prevalent throughout the surveyed provinces. Pathogenicity test was carried out by using two different methods: seed inoculation and head inoculation. Results showed that F. sibiricum isolates were the most aggressive on the seed and head. A. sclerotigenum isolates were not pathogenic to seeds, and were developed less symptoms to the head compared to other species. Data analyses showed that the correlation of the germination potential, germination index, and dry weight of seed inoculation and disease index of plant inoculation had a highly significant negative correlation (P < 0.001). These results showed that the development of HB might be predicted by seed tests for this species. A. sclerotigenum and N. graminearum causing HB are being firstly reported on oat in the world. Similarly, F. proliferatum, F. avenaceum, F. poae and F. sibiricum causing oat HB are firstly reported in China.


Asunto(s)
Avena , Fusarium , Filogenia , Enfermedades de las Plantas , Avena/microbiología , Enfermedades de las Plantas/microbiología , China , Fusarium/genética , Fusarium/clasificación , Fusarium/aislamiento & purificación , Fusarium/patogenicidad , ADN de Hongos/genética , Acremonium/genética , Acremonium/clasificación , Acremonium/aislamiento & purificación
5.
Microb Pathog ; 190: 106594, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38458267

RESUMEN

Fusarium wilt or Panama disease of banana caused by the hemibiotroph fungus, Fusarium odoratissimum, also known as F. oxysporum f.sp. cubense Tropical Race 4 is a serious threat to banana production worldwide. Being the world's largest grower and the origins of bananas in its northeast region, India is particularly vulnerable to this deadly fungus. In the present study, a total of 163 Fusarium isolates from infected banana were characterized for their pathogenic traits. Considering the variability in the Fusarium, the contaminated banana plants were collected from five districts of Uttar Pradesh and Bihar, two major primary infection states of India. All the isolates were screened using universal and specific primers to identify the F. odoratissimum strains. The identified F. odoratissimum strains were subjected to in vivo pathogenicity assessment using the susceptible banana cultivar 'Grand Naine'. The identified six most virulent strains were further characterized for their pathogenicity via in vivo bipartite interaction in terms of biochemical assays. Assessment of in vivo pathogenicity through qRT-PCR for three pathogenesis responsive genes, Six 1a (Secreted in xylem), Snf (Sucrose non-fermenting) and ChsV (Chitinase V), ascertained that the identified F. odoratissimum strains exhibit both intra- and inter-specific variability. The variability of F. odoratissimum strains signifies its importance for the assessment of spread of infection at specific sites to enable efficient management strategy of Fusarium wilt in banana.


Asunto(s)
Fusarium , Musa , Enfermedades de las Plantas , Musa/microbiología , Fusarium/genética , Fusarium/patogenicidad , Fusarium/aislamiento & purificación , Fusarium/clasificación , Enfermedades de las Plantas/microbiología , India , Virulencia/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Filogenia
6.
N Engl J Med ; 390(6): 522-529, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38324485

RESUMEN

A multinational outbreak of nosocomial fusarium meningitis occurred among immunocompetent patients who had undergone surgery with epidural anesthesia in Mexico. The pathogen involved had a high predilection for the brain stem and vertebrobasilar arterial system and was associated with high mortality from vessel injury. Effective treatment options remain limited; in vitro susceptibility testing of the organism suggested that it is resistant to all currently approved antifungal medications in the United States. To highlight the severe complications associated with fusarium infection acquired in this manner, we report data, clinical courses, and outcomes from 13 patients in the outbreak who presented with symptoms after a median delay of 39 days.


Asunto(s)
Brotes de Enfermedades , Fusariosis , Fusarium , Enfermedad Iatrogénica , Meningitis Fúngica , Humanos , Antifúngicos/uso terapéutico , Fusariosis/epidemiología , Fusariosis/etiología , Fusarium/aislamiento & purificación , Enfermedad Iatrogénica/epidemiología , Meningitis Fúngica/epidemiología , Meningitis Fúngica/etiología , México/epidemiología , Brotes de Enfermedades/estadística & datos numéricos , Internacionalidad , Inmunocompetencia , Farmacorresistencia Fúngica , Analgesia Epidural/efectos adversos
7.
Braz. j. biol ; 83: 1-7, 2023. ilus, tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468917

RESUMEN

Dengue fever vectored by the mosquito Aedes aegypti is one of the most rapidly spreading insect-borne diseases. Current reliance of dengue vector control is mostly on chemical insecticides. Growing insecticide resistance in the primary mosquito vector, Aedes aegypti, limits the effectiveness of vector control through chemical insecticides. These chemical insecticides also have negative environmental impacts on animals, plants and human health. Myco-biocontrol agents are naturally occurring organisms and are found to be less damaging to the environment as compared to chemical insecticides. In the present study, entomopathogenic potential of local strains of fungi isolated from soil was assessed for the control of dengue vector. Local fungal isolates presents better alternative to introducing a foreign biocontrol strain, as they may be better adapted to environmental conditions of the area to survive and may have more entomopathogenic efficacy against target organism. Larvicidal efficacy of Fusarium equiseti and Fusarium proliferatum was evaluated against Aedes aegypti. Local strains of F. equiseti (MK371718) and F. proliferatum (MK371715) were isolated from the soil of Changa Manga Forest, Pakistan by using insect bait method. Larvicidal activity of two Fusarium spp. was tested against forth instar larvae of A. aegypti in the laboratory, using concentrations 105, 106, 107 and 108 conidia /ml. LC50 values for F. equiseti after 24h, 48h, 72h and 96h of exposure were recorded as 3.8x108, 2.9x107, 2.0x107, and 7.1x106 conidia /ml respectively while LC50 values for F. proliferatum were recorded as 1.21x108, 9.6x107, 4.2x107, 2.6x107 conidia /ml respectively after 24h, 48h, 72h and 96h of exposure. The results indicate that among two fungal strains F. equiseti was found to be more effective in terms of its larvicidal activity than F. proliferatum against larvae of A. aegypti.


A dengue transmitida pelo mosquito Aedes aegypti é uma das doenças transmitidas por insetos de propagação mais rápida. A dependência atual do controle do vetor da dengue é principalmente de inseticidas químicos. O aumento da resistência a inseticidas no principal vetor do mosquito, Aedes aegypti, limita a eficácia do controle do vetor por meio de inseticidas químicos. Esses inseticidas químicos também têm impactos ambientais negativos sobre os animais, plantas e saúde humana. Os agentes de micobiocontrole são organismos que ocorrem naturalmente e são menos prejudiciais ao meio ambiente em comparação com os inseticidas químicos. No presente estudo, avaliou se o potencial entomopatogênico de cepas locais de fungos isolados do solo para o controle do vetor da dengue. Isolados de fungos locais apresentam melhor alternativa para a introdução de uma cepa de biocontrole estrangeira, pois podem ser mais bem adaptados às condições ambientais da área para sobreviver e podem ter maior eficácia entomopatogênica contra o organismo-alvo. A eficácia larvicida de Fusarium equiseti e Fusarium proliferatum foi avaliada contra Aedes aegypti. Cepas locais de F. equiseti (MK371718) e F. proliferatum (MK371715) foram isoladas do solo de Changa Manga Forest, Paquistão, usando o método de isca para insetos. Atividade larvicida de dois Fusarium spp. foi testado contra larvas de quarto ínstar de A. aegypti em laboratório, nas concentrações 105, 106, 107 e 108 conídios / ml. Os valores de LC50 para F. equiseti após 24 h, 48 h, 72 h e 96 h de exposição foram registrados como 3,8x 108, 2,9x107, 2,0x107 e 7,1x106 conídios / ml, respectivamente, enquanto os valores de LC50 para F. proliferatum foram registrados como 1,21x108, 9,6 x107, 4,2x107, 2,6x107 conídios / ml, respectivamente, após 24 h, 48 h, 72 h e 96 h de exposição. Os resultados indicam que entre duas cepas de fungos F. equiseti se mostrou mais eficaz em termos de atividade [...].


Asunto(s)
Animales , Aedes , Control Biológico de Vectores/métodos , Fusarium/aislamiento & purificación , Fusarium/patogenicidad
9.
Mar Drugs ; 20(2)2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-35200618

RESUMEN

In many African countries, the Bayoud is a common disease spread involving the fungus Fusarium oxusporum f. sp. albedinis (Foa). The induction of plant natural defenses through the use of seaweed polysaccharides to help plants against pathogens is currently a biological and ecological approach that is gaining more and more importance. In the present study, we used alginate, a natural polysaccharide extracted from a brown algae Bifurcaria bifurcata, to activate date palm defenses, which involve phenylalanine ammonia-lyase (PAL), a key enzyme of phenylpropanoid metabolism. The results obtained showed that at low concentration (1 g·L-1), alginate stimulated PAL activity in date palm roots 5 times more compared to the negative control (water-treated) after 24 h following treatment and 2.5 times more compared to the laminarin used as a positive stimulator of plant natural defenses (positive control of induction). Using qRT-PCR, the expression of a selection of genes involved in three different levels of defense mechanisms known to be involved in response to biotic stresses were investigated. The results showed that, generally, the PAL gene tested and the genes encoding enzymes involved in early oxidative events (SOD and LOX) were overexpressed in the alginate-treated plants compared to their levels in the positive and negative controls. POD and PR protein genes selected encoding ß-(1,3)-glucanases and chitinases in this study did not show any significant difference between treatments; suggesting that other genes encoding POD and PR proteins that were not selected may be involved. After 17 weeks following the inoculation of the plants with the pathogen Foa, treatment with alginate reduced the mortality rate by up to 80% compared to the rate in control plants (non-elicited) and plants pretreated with laminarin, which agrees with the induction of defense gene expression and the stimulation of natural defenses in date palm with alginate after 24 h. These results open promising prospects for the use of alginate in agriculture as an inducer that triggers immunity of plants against telluric pathogens in general and of date palm against Fusarium oxysporum f. sp. albedinis in particular.


Asunto(s)
Alginatos/farmacología , Phaeophyceae/química , Phoeniceae/microbiología , Enfermedades de las Plantas/prevención & control , Alginatos/aislamiento & purificación , Fusariosis/prevención & control , Fusarium/aislamiento & purificación , Regulación de la Expresión Génica de las Plantas/genética , Glucanos/farmacología , Lipooxigenasa/metabolismo , Phoeniceae/genética , Enfermedades de las Plantas/microbiología , Metabolismo Secundario , Superóxido Dismutasa/metabolismo
10.
Toxins (Basel) ; 14(2)2022 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-35202130

RESUMEN

Fusarium head blight (FHB) caused by fungi of the genus Fusarium is one of the most dangerous crop diseases, which has a wide geographic distribution and causes severe economic losses in the production of major cereal species. The infection leads to the accumulation of mycotoxins in grains, which compromises its suitability for human and animal consumption. The study demonstrated that grain samples from warmer regions of Poland, including Sulejów and Tomaszów Boleslawicki (results differed across years of the study), were colonized mainly by F. graminearum and were most highly contaminated with deoxynivalenol (DON). Samples from Northeastern Poland, i.e., Ruska Wies, which is located in a cooler region, were characterized by a predominance of Fusarium species typical of the cold climate, i.e., Fusarium poae and Penicillium verrucosum. A Spearman's rank correlation analysis revealed that the severity of grain infection with F. avenaceum/F. tricinctum was affected by the mean daily temperature and high humidity in May, and the corresponding values of the correlation coefficient were determined at R = 0.54 and R = 0.50. Competitive interactions were observed between the F. avenaceum/F. tricinctum genotype and DON-producing F. culmorum and F. graminearum, because the severity of grain infections caused by these pathogens was bound by a negative correlation.


Asunto(s)
Grano Comestible/química , Grano Comestible/microbiología , Fusarium/aislamiento & purificación , Tricotecenos/análisis , Triticum/química , Triticum/microbiología , Clima , ADN de Hongos/análisis , Monitoreo del Ambiente , Contaminación de Alimentos/análisis , Fusarium/genética , Polonia
11.
Toxins (Basel) ; 14(1)2022 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-35051022

RESUMEN

Fusarium head blight (FHB) is an economically important plant disease. Some Fusarium species produce mycotoxins that cause food safety concerns for both humans and animals. One especially important mycotoxin-producing fungus causing FHB is Fusarium graminearum. However, Fusarium species form a disease complex where different Fusarium species co-occur in the infected cereals. Effective management strategies for FHB are needed. Development of the management tools requires information about the diversity and abundance of the whole Fusarium community. Molecular quantification assays for detecting individual Fusarium species and subgroups exist, but a method for the detection and quantification of the whole Fusarium group is still lacking. In this study, a new TaqMan-based qPCR method (FusE) targeting the Fusarium-specific elongation factor region (EF1α) was developed for the detection and quantification of Fusarium spp. The FusE method was proven as a sensitive method with a detection limit of 1 pg of Fusarium DNA. Fusarium abundance results from oat samples correlated significantly with deoxynivalenol (DON) toxin content. In addition, the whole Fusarium community in Finnish oat samples was characterized with a new metabarcoding method. A shift from F. culmorum to F. graminearum in FHB-infected oats has been detected in Europe, and the results of this study confirm that. These new molecular methods can be applied in the assessment of the Fusarium community and mycotoxin risk in cereals. Knowledge gained from the Fusarium community analyses can be applied in developing and selecting effective management strategies for FHB.


Asunto(s)
Avena/microbiología , Contaminación de Alimentos/análisis , Microbiología de Alimentos/métodos , Fusarium/aislamiento & purificación , Micotoxinas/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Código de Barras del ADN Taxonómico , Grano Comestible/microbiología , Finlandia , Fusarium/clasificación , Límite de Detección , Micobioma
13.
Acta Ophthalmol ; 100(2): 159-163, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34031997

RESUMEN

PURPOSE: To report an epidemiological update of documented fungal keratitis (FK) in a French tertiary ophthalmological centre from 2014 to 2018 in comparison with a previous period from 1993 to 2008. METHODS: Sixty-two consecutive FK documented by microbiological corneal scrapings were compared with the 64 FK of the previous study. Amphotericin B and voriconazole eye drops were administered hourly. Population characteristics, clinical findings, aetiological organisms and treatments were analysed. RESULTS: The most frequently identified fungi were Fusarium (61%), Aspergillus (6.5%) and Candida (5%). Thirty out of 44 cases examined with in vivo confocal microscopy (IVCM) presented filaments. Ten required conventional cross-linking, 9 therapeutic penetrating keratoplasty, and 2 enucleation. Risk factors significantly associated with the absence of response to medical treatment were patient age (p = 0.01), presence of a deep stromal infiltrate at presentation (p = 0.04) and high numbers of filaments in IVCM images (p = 0.01). The two populations were comparable in age, but not in sex ratio males/females (18/44 versus 37/26 in the previous study; p = 0.001). The frequency of contact lens-associated infection increased from 35.5% to 71% (p = 0.0001) between the two periods. Since then, filamentous FK increased from 69% (44/64) to 95% (59/62) (p = 0.0001). A history of keratoplasty was less frequently reported during the last period (3.2% (2/62) versus 17% (11/64) of cases (p = 0.01)). A clear decrease in the frequency of therapeutic keratoplasty was noted from 39% (25/64) to 14% (9/62) (p = 0.02). CONCLUSION: The frequency of filamentous keratomycosis is currently increasing. Elderly patients and the presence of numerous filaments in IVCM are associated with poor clinical outcomes.


Asunto(s)
Infecciones Fúngicas del Ojo/epidemiología , Queratitis/epidemiología , Adulto , Anciano , Aspergillus/aislamiento & purificación , Candida/aislamiento & purificación , Estudios de Casos y Controles , Infecciones Fúngicas del Ojo/diagnóstico , Infecciones Fúngicas del Ojo/microbiología , Femenino , Francia/epidemiología , Fusarium/aislamiento & purificación , Humanos , Queratitis/diagnóstico , Queratitis/microbiología , Masculino , Persona de Mediana Edad , Prevalencia
14.
J Microbiol Methods ; 192: 106379, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34808145

RESUMEN

This work addresses the mathematical model building to detect the diameter of the inhibition zone of gilaburu (Viburnum opulus L.) extract against eight different Fusarium strains isolated from diseased potato tubers. Gilaburu extracts were obtained with acetone, ethanol or methanol. The isolated Fusarium strains were: F. solani, F. oxysporum, F. sambucinum, F. graminearum, F. coeruleum, F. sulphureum, F. auneaceum and F. culmorum. In general, it was observed that ethanolic extracts showed highest antifungal activity. The antifungal activity of extracts was evaluated with machine learning (ML) methods. Several ML methods (classification and regression trees (CART), support vector machines (SVM), k-Nearest Neighbors (k-NN), artificial neural network (ANN), ensemble algorithms (EA), AdaBoost (AB) algorithm, gradient boosting (GBM) algorithm, random forests (RF) bagging algorithm and extra trees (ET)) were applied and compared for modeling fungal growth. From this research, it is clear that ML methods have the lowest error level. As a result, ML methods are reliable, fast, and cheap tools for predicting the antifungal activity of gilaburu extracts. These encouraging results will attract more research efforts to implement ML into the field of food microbiology instead of traditional methods.


Asunto(s)
Antifúngicos/farmacología , Fusarium/crecimiento & desarrollo , Aprendizaje Automático , Extractos Vegetales/farmacología , Solanum tuberosum/microbiología , Viburnum/química , Algoritmos , Antioxidantes/farmacología , Pruebas Antimicrobianas de Difusión por Disco/métodos , Microbiología de Alimentos , Fusarium/efectos de los fármacos , Fusarium/aislamiento & purificación
15.
Toxins (Basel) ; 13(12)2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34941693

RESUMEN

The current study investigated the fungal diversity in freshly harvested oat samples from the two largest production regions in Brazil, Paraná (PR) and Rio Grande do Sul (RS), focusing primarily on the Fusarium genus and the presence of type B trichothecenes. The majority of the isolates belonged to the Fusarium sambucinum species complex, and were identified as F. graminearum sensu stricto (s.s.), F. meridionale, and F. poae. In the RS region, F. poae was the most frequent fungus, while F. graminearum s.s. was the most frequent in the PR region. The F. graminearum s.s. isolates were 15-ADON genotype, while F. meridionale and F. poae were NIV genotype. Mycotoxin analysis revealed that 92% and 100% of the samples from PR and RS were contaminated with type B trichothecenes, respectively. Oat grains from PR were predominantly contaminated with DON, whereas NIV was predominant in oats from RS. Twenty-four percent of the samples were contaminated with DON at levels higher than Brazilian regulations. Co-contamination of DON, its derivatives, and NIV was observed in 84% and 57.7% of the samples from PR and RS, respectively. The results provide new information on Fusarium contamination in Brazilian oats, highlighting the importance of further studies on mycotoxins.


Asunto(s)
Avena/química , Avena/microbiología , Fusarium/aislamiento & purificación , Tricotecenos Tipo B/análisis , Brasil , Grano Comestible/química , Grano Comestible/microbiología , Contaminación de Alimentos/análisis , Fusarium/clasificación , Fusarium/genética , Micotoxinas/análisis , Tricotecenos/análisis
16.
Biomed Res Int ; 2021: 7913950, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34970627

RESUMEN

Trichoderma spp. are widely distributed in natural habitats and have been evaluated as a potential biocontrol agent (BCA) for disease control and plant growth promotion. In this study, 1308 Trichoderma strains were obtained from the plant rhizosphere soil, above-ground plants, and decaying wood from natural habitats in China. Among them, 49 Trichoderma strains showed a good inhibitory effect, especially against Botrytis cinerea, Fusarium oxysporum, and Colletotrichum gloeosporioides with inhibition rate above 85% in the dual culture test. Among these 49 strains, the 13 strains with broad-spectrum inhibitory effects also significantly promoted the seed germination of five crops (rice, cucumber, tomato, melon, and pakchoi) and root growth of four crop seedlings (watermelon, tomato, eggplant, and chili). Furthermore, these strains showed effective colonization in the rhizosphere and root of cucumber. Trichoderma strains SC012 and NX043 showed the highest chitinase and ß-1,3-glucanase activity among all strains. Based on the morphological characterization and phylogenetic analysis of the nuclear ribosomal internal transcribed spacer (ITS) and translation elongation factor 1 (tef1), twelve Trichoderma strains were identified as Trichoderma asperellum and one as Trichoderma afroharzianum. This study suggests that the 13 Trichoderma strains are promising BCAs and could be developed as biofertilizers and biological pesticides for agricultural applications.


Asunto(s)
Hypocreales/clasificación , Hypocreales/aislamiento & purificación , Agricultura/métodos , Agentes de Control Biológico/metabolismo , Botrytis/genética , Botrytis/aislamiento & purificación , China , Productos Agrícolas/microbiología , Fusarium/genética , Fusarium/aislamiento & purificación , Hypocreales/genética , Filogenia , Desarrollo de la Planta/genética , Enfermedades de las Plantas/microbiología , Microbiología del Suelo
17.
J Gen Virol ; 102(12)2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34850675

RESUMEN

An extensive screening survey was conducted on Pakistani filamentous fungal isolates for the identification of viral infections. A total of 396 fungal samples were screened, of which 36 isolates were found double-stranded (ds) RNA positive with an overall frequency of 9% when analysed by a classical dsRNA isolation method. One of 36 dsRNA-positive strains, strain SP1 of a plant pathogenic fungus Fusarium mangiferae, was subjected to virome analysis. Next-generation sequencing and subsequent completion of the entire genome sequencing by a classical Sanger sequencing method showed the SP1 strain to be co-infected by 11 distinct viruses, at least seven of which should be described as new taxa at the species level according to the ICTV (International Committee on Taxonomy of Viruses) species demarcation criteria. The newly identified F. mangiferae viruses (FmVs) include two partitivirids, one betapartitivirus (FmPV1) and one gammapartitivirus (FmPV2); six mitovirids, three unuamitovirus (FmMV2, FmMV4, FmMV6), one duamitovirus (FmMV5), and two unclassified mitovirids (FmMV1, FmMV3); and three botourmiavirids, two magoulivirus (FmBOV1, FmBOV3) and one scleroulivirus (FmBOV2). The number of coinfecting viruses is among the largest ones of fungal coinfections. Their molecular features are thoroughly described here. This represents the first large virus survey in the Indian sub-continent.


Asunto(s)
Virus Fúngicos/genética , Fusarium/virología , Virus Fúngicos/clasificación , Virus Fúngicos/ultraestructura , Fusarium/aislamiento & purificación , Genoma Viral/genética , Pakistán , Filogenia , Enfermedades de las Plantas/microbiología , Plantas/microbiología , Virus ARN/clasificación , Virus ARN/genética , Virus ARN/ultraestructura , ARN Viral/genética , Proteínas Virales/genética , Viroma/genética
18.
Pak J Biol Sci ; 24(10): 1015-1021, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34842370

RESUMEN

<b>Background and Objective:</b> Endophytic fungi live in plant tissue and show no symptoms of disease in their host plants. It is known that endophytes as biological agents, can control plant diseases. In this study, isolated endophytic fungi from healthy Dayak Onion flowers were used as biocontrol agents in the control of the pathogenic fungi <i>Fusarium </i>spp. that causes molar disease in shallot plants. <b>Materials and Methods:</b> This study identifies the type of endophytic fungi molecularly isolated from Dayak onion flowers and determine the antagonistic effect of the endophytic extract against <i>Fusarium </i>spp. screening for endophytic fungi as antagonizing agents is carried out using the poisoned food method. <b>Results:</b> The results showed that two endophytic fungi isolates were obtained from healthy Dayak onion flowers, namely, EnI which was identified with the primers ITS1 and ITS4 as <i>Fusarium solani</i> and EnK as <i>Neoscytalidium </i>sp. <i>Fusarium</i> wilt caused by pathogenic fungi was identified as <i>Fusarium oxysporum</i>. The inhibitory percentage of EnI extract against the pathogenic fungus <i>Fusarium oxysporum</i> was 71.09% (high inhibition percentage) and the inhibition percentage of EnK was 38.54% (low inhibition percentage). <b>Conclusion:</b> Based on the results of this study, recommend using the endophytic fungus EnI extracts (<i>Fusarium solani </i>), extracted from Dayak onion flowers to control the pathogen <i>Fusarium oxysporum</i>.


Asunto(s)
Flores/microbiología , Fusarium/aislamiento & purificación
19.
Molecules ; 26(21)2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34770893

RESUMEN

The aim of the study was to determine the effectiveness of selected seven commercial essential oils (EsO) (grapefruit, lemongrass, tea tree (TTO), thyme, verbena, cajeput, and Litsea cubeba) on isolates of common Central European parasitic fungal species of Fusarium obtained from infected wheat kernels, and to evaluate the oils as potential natural fungicides. The study was conducted in 2 stages. At each stage, the fungicidal activity of EsO (with concentrations of 0.025; 0.05; 0.125; 0.25; 0.50; 1.0, and 2.0%) against Fusarium spp. was evaluated using the disc plate method and zones of growth inhibition were measured. At the first stage, the fungistatic activity of EsO was evaluated against four species of Fusarium from the Polish population (F. avenaceum FAPL, F. culmorum FCPL, F. graminearum FGPL and F. oxysporum FOPL). The correlation coefficient between the mycelial growth rate index (T) and the fungistatic activity (FA) was calculated. At the second stage, on the basis of the mycelium growth rate index, the effectiveness of the EsO in limiting the development of Fusarium isolates from the German population (F. culmorum FC1D, F. culmorum FC2D, F. graminearum FG1D, F. graminearum FG2D and F. poae FP0D) was assessed. The first and second stage results presented as a growth rate index were then used to indicate essential oils (as potential natural fungicides) effectively limiting the development of various common Central European parasitic species Fusarium spp. Finally, the sensitivity of four Fusarium isolates from the Polish population and five Fusarium isolates from the German population was compared. The data were compiled in STATISTICA 13.0 (StatSoft, Inc, CA, USA) at the significance level of 0.05. Fusarium isolates from the German population were generally more sensitive than those from the Polish population. The sensitivity of individual Fusarium species varied. Their vulnerability, regardless of the isolate origin, in order from the most to the least sensitive, is as follows: F. culmorum, F. graminearum, F. poae, F. avenaceum and F. oxysporum. The strongest fungicidal activity, similar to Funaben T, showed thyme oil (regardless of the concentration). Performance of citral oils (lemongrass and Litsea cubeba) was similar but at a concentration above 0.025%.


Asunto(s)
Antifúngicos/farmacología , Fusarium/efectos de los fármacos , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Triticum/química , Antifúngicos/química , Grano Comestible/química , Grano Comestible/microbiología , Europa (Continente) , Fusarium/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/química , Extractos Vegetales/química , Triticum/microbiología
20.
Cornea ; 40(11): 1453-1461, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34633358

RESUMEN

PURPOSE: Fungal keratitis (FK) is a serious ophthalmic disease with a potentially devastating outcome that seems to be increasing in recent years. The use of contact lenses (CLs) was evaluated as a risk factor for FK to determine possible differences in course and outcome. METHODS: Data from 173 cases reported in the German FK registry until August 2019 were evaluated regarding CL behavior, other ophthalmological and general risk factors, age, sex, identified pathogens, conservative and surgical therapy, visual acuity, and findings at admission and follow-up. RESULTS: One hundred seventy-four eyes from 173 patients between 2000 and 2019 were included [64.4% women, median age 54 (39; 72) years]; 49.7% wore CL, of which 81.3% were soft CL, and 50.3% had no history of contact lens use (NCL). CL users were significantly more often women and otherwise healthy (CL: 80.2% vs. NCL: 48.9%; P < 0.0001). The spectrum of pathogens among CL users showed a significantly higher proportion of infections with filamentous pathogens, in particular Fusarium sp. (total filament: CL 69.8% vs. NCL 27.3%; P = 0.0001; Fusarium sp.: CL 50.0% vs. NCL 14.8%; P < 0.0001). Overall, 54.6% required keratoplasty and 8.6% enucleation. CONCLUSIONS: CLS are the most important risk factor for FK in Germany. With CLs, typically, the infection is caused by molds, and patients are comparably younger and otherwise healthy. Often, extensive surgery is needed. To evaluate changes in the pathogen and resistance spectrum and to further monitor possible CL-related risk factors, a consistent collection of data remains paramount.


Asunto(s)
Lentes de Contacto/efectos adversos , Córnea/diagnóstico por imagen , Infecciones Fúngicas del Ojo/etiología , Fusariosis/etiología , Fusarium/aislamiento & purificación , Queratitis/etiología , Sistema de Registros , Adulto , Anciano , Lentes de Contacto/microbiología , Córnea/microbiología , Infecciones Fúngicas del Ojo/epidemiología , Infecciones Fúngicas del Ojo/microbiología , Femenino , Fusariosis/diagnóstico , Fusariosis/microbiología , Alemania/epidemiología , Humanos , Incidencia , Queratitis/epidemiología , Queratitis/microbiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos
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