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1.
Biosci. j. (Online) ; 34(5): 1281-1286, sept./oct. 2018.
Artigo em Inglês | LILACS | ID: biblio-967317

RESUMO

Soybean Asian rust and white mold stand out to cause great problems to soybean producing regions in Brazil. The aim of this study was to evaluate the partial resistance of soybean lines to Asian rust and white mold. In order to assess the resistance of soybean to Asian rust, 19 early maturing soybean lines were used in an experiment in a greenhouse. Four severity evaluation were carried and the area under the disease progress curve was calculated. The productivity of those lines was evaluated in the field. In a second experiment, the resistance to Sclerotinia sclerotiorum was assessed under greenhouse conditions. When the plants were in the V2 stage, the inoculation was carried by cutting the main stem and inserting a ferrule containing the fungal mycelium. Seventeen soybean lines and the controls Emgopa 316 and Nidera RR 7255 were evaluated. The averages were grouped by the Scott Knott test by using the software Assistat. The lines L203 and L279 showed partial resistance to Phakopsora pachyrhizi and good productivity. The inoculation method was efficient in assessing the resistance to S. sclerotiorum. The lines L203, L268, L266, L226, L144 and L267 were resistant to the infection of S. sclerotiorum.


A Ferrugem Asiática e o Mofo-Branco da soja se destacam por causar grandes problemas em regiões produtoras de soja do Brasil. O objetivo deste trabalho foi avaliar a resistência parcial de linhagens de soja à ferrugem asiática e ao mofo branco da soja. Para avaliação da resistência à ferrugem asiática da soja foram utilizadas 19 linhagens de ciclo precoce em ensaio em casa de vegetação. Foram realizadas quatro avaliações de severidade e calculada a área abaixo da curva de progresso da doença. Avaliou-se a produtividade dessas mesmas linhagens a campo. Em um segundo ensaio, avaliou-se a resistência à S. sclerotiorum em casa de vegetação. Quando as plantas estavam em V2 realizou-se a inoculação através do corte da haste principal e inserção de ponteira contendo o micélio do fungo. Foram avaliadas 18 linhagens de soja e duas testemunhas, Emgopa 316 e Nidera RR 7255. As médias foram comparadas pelo teste de Scott Knott, através do Assistat. As linhagens L203 e L279 demonstraram resistência parcial à P. pachyrhizi e apresentaram boa produtividade. O método de inoculação mostrou-se eficiente na avaliação da resistência à S. sclerotiorum. As linhagens L203, L268, L266, L226, L144, L267 mostraram-se resistentes à infecção por S. sclerotiorum.


Assuntos
Ascomicetos , Soja , Micélio , Resistência à Doença , Phakopsora pachyrhizi , Fungos
2.
Braz. j. microbiol ; 49(3): 632-640, July-Sept. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951795

RESUMO

Abstract The present study conducted a genetic characterization and determined growth rate and biomass production in solid and liquid media, using strains obtained from wild edible sporomes of Lyophyllum that grow in high mountains. Vegetative isolation was used to obtain a total of four strains, which were divided into two clades within the section Difformia: Lyophyllum sp. and Lyophyllum aff. shimeji. Growth rate and biomass production were influenced by both the culture media and the strains. In a potato dextrose agar medium, the strains presented a higher growth rate, while in a malt extract-peptone and yeast agar medium, the growth rate was lower, but with a higher biomass production that was equal to that in the malt extract-peptone and yeast liquid medium.


Assuntos
Agaricales/crescimento & desenvolvimento , Agaricales/genética , Cinética , Biomassa , Meios de Cultura/metabolismo , Meios de Cultura/química , Micélio/crescimento & desenvolvimento , Micélio/genética , Micélio/metabolismo , Micélio/química , Agaricales/metabolismo , Agaricales/química , Fermentação , México
3.
Braz. j. microbiol ; 49(2): 370-377, Apr.-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889219

RESUMO

Abstract Agaricus subrufescens is a basidiomycete which is studied because of its medicinal and gastronomic importance; however, less attention has been paid to its preservation. This study aimed to evaluate the effect of sucrose addition to substrate and cryotube on the viability of Agaricus subrufescens cryopreserved at -20 °C and at -75 °C for one and two years. Zero, 10% or 20% sucrose was added to potato dextrose agar or wheat grain. The mycelia were cryopreserved in the absence of cryoprotectant or with sucrose solutions at 15%, 30% or 45%. After one or two years at -75 °C or at -20 °C, mycelia were thawed and evaluated about viability, initial time of growth, colony diameter and genomic stability. Cryopreservation at -20 °C is not effective to keep mycelial viability of this fungus. Cryopreservation at -75 °C is effective when sucrose is used in substrates and/or cryotubes. Without sucrose, cryopreservation at -75 °C is effective only when wheat grains are used. Physiological characteristic as mycelial colony diameter is negatively affected when potato dextrose agar is used and unaffected when wheat grain is used after two-year cryopreservation at -75 °C. The fungus genome does not show alteration after two-year cryopreservation at -75 °C.


Assuntos
Agaricus/crescimento & desenvolvimento , Criopreservação/métodos , Crioprotetores/metabolismo , Congelamento , Sementes/microbiologia , Sacarose/metabolismo , Triticum/microbiologia , Agaricus/efeitos da radiação , Instabilidade Genômica/efeitos da radiação , Viabilidade Microbiana/efeitos da radiação , Micélio/crescimento & desenvolvimento , Micélio/efeitos da radiação , Fatores de Tempo
4.
Biosci. j. (Online) ; 33(3): 566-571, may/jun. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-966213

RESUMO

Although the productivity of common bean in Tocantins is economically favorable, it has been infected by various pathogens found in soil. Among the major diseases is the web blight and root rot caused by Rhizoctonia solani and collar rot caused by the fungus Sclerotium rolfsii. This study aimed to evaluate the fungitoxic activity of methanol extracts of eight plant species on the inhibition of mycelial growth of S. rolfsii and R. solani. The fungitoxic activities were carried out over the inhibition of mycelial growth by means in vitro assays. The extracts were applied in concentrations of 250, 500, 1000, 2500 e 5000 µg ml-1 in PDA culture medium. In bioassays, it was found the significant effect of plant, concentration and also their interaction on the antifungal activity of the extracts. However, some extracts showed no inhibition of mycelial growth of the pathogens studied. Among those who had higher inhibitions is the extract of Lantana trifolia, which inhibited the mycelial growth of S. rolfsii in all concentrations, being the same as 97% for the highest concentration. When the methanol extract of Piper amplum Kunth, inhibition of the highest concentration was 83% for S. rolfsii and 74% for R. solani. These results show the potential of methanolic extract of Lantana trifolia and Piper amplum Kunth in the control set of plant pathogens studied.


Apesar da produtividade do feijão comum no Tocantins ser economicamente favorável, o mesmo pode ser infectado por vários patógenos habitantes do solo, dentre as principais doenças encontra-se a mela e a podridão radicular causadas pelo fungo Rhizoctonia solani e a podridão do colo causada pelo fungo Sclerotium rolfsii. Este trabalho teve como objetivo avaliar a atividade fungitóxica dos extratos metanólicos de oito espécies vegetais sobre a inibição do crescimento micelial de Sclerotium rolfsii e Rhizoctonia solani. As atividades fungitóxicas foram realizadas perante a inibição do crescimento micelial por meio de ensaios in vitro, sendo os extratos aplicados nas concentrações de 250, 500, 1000, 2500 e 5000 µg ml-1 em meio de cultura BDA. Observou-se o efeito significativo dos fatores planta, concentração e também da interação destes sobre as atividades fungitóxicas. No entanto, alguns extratos não apresentaram inibição do crescimento micelial dos fitopatógenos estudados. Entre os que apresentaram maiores inibições encontra-se o extrato de Lantana trifolia, que inibiu o crescimento micelial do S. rolfsii em todas as concentrações, sendo o mesmo de 97% para a maior concentração. Já a concentração mais elevada do extrato metanólico de Piper amplum apresentou inibição de 83% sobre o crescimento micelial de S. rolfsii e 74% sobre o crescimento micelial de R. solani. Tais resultados evidenciam a potencialidade dos extratos metanólicos das folhas de Lantana trifolia e de Piper amplum no controle dos fitopatógenos estudados.


Assuntos
Rhizoctonia , Micélio/crescimento & desenvolvimento , Phaseolus , Fungos , Fungicidas Industriais , Noxas
5.
Biosci. j. (Online) ; 32(6): 1679-1688, nov./dec. 2016. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-965837

RESUMO

The disruption of the delicate balance between the generation of reactive oxygen species (ROS) and antioxidant scavenging systems can lead to many health problems. Polysaccharides extracted from fungi fruit body and myceliums have several potential health benefits. In this study, the antioxidant capacity and cell protective effects of a polysaccharide isolated from Lentinus edodes mycelia (LMP) were investigated. The antioxidant properties of LMP were screened using radical scavenging (1, 1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and superoxide anion), reducing power and inhibition of lipid peroxidation assays. Intracellular reactive oxygen species (ROS), in response to H2O2, was determined by the dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay. Rat insulinoma (INS-1) cells apoptosis was detected using flow cytometry analysis. The results showed that LMP exhibited significantly strong radical scavenging activity. At the concentration of 2.0 mg mL-1, DPPH radical, hydroxyl radical, and superoxide anion radical scavenging rates are 80.32 ± 2.58%, 92.56 ± 3.11% and 93.73 ± 2.82%, respectively. The reducing power and inhibition of lipid peroxidation activity of LMP were as strong as the positive control. LMP alleviated the intracellular reactive oxygen species level and inhibited islet cell apoptosis significantly. The results open perspectives for studies of LMP in the treatment of diabetes.


O estresse oxidativo tem uma função biológica importante em muitos organismos. A ruptura do equilíbrio delicado entre a geração de espécies reativas de oxigênio (ROS) e sistemas de eliminação de antioxidantes pode levar a muitos problemas de saúde. Polissacarídeos extraídos do corpo fungos frutas e micélio têm vários benefícios potenciais para a saúde. Neste estudo, foram investigados os efeitos celulares e capacidade de proteção antioxidante de um polissacarídeo isolado a partir de Lentinus edodes micélios (LMP). As propriedades antioxidantes da LMP foram rastreadas utilizando eliminação de radicais (1, 1-difenil-2-picrilhidrazil (DPPH), hidroxilo e anião superóxido), e a redução da potência de inibição de ensaios de peroxidação lipídica. Espécies reativas de oxigénio intracelulares (ROS), em resposta ao H2O2, foi determinada pelo ensaio de diacetato de dicloro-di-hidro-f luoresceina (DCFH-DA). INS-1 células a apoptose foi detectada utilizando análise de citometria de fluxo. Os resultados mostraram que LMP exibiu significativamente forte atividade de eliminação de radicais. Na concentração de 2 mg mL-1, DPPH radical, radical hidroxilo e anião superóxido velocidades de eliminação de radicais livres são 80,32 ± 2,58%, 92,56 ± 3,11% 93,73 ± 2,82%, respectivamente. O poder redutor e inibição da peroxidação lipídica de LMP foram tão forte quanto o controlo positivo. LMP aliviou a nível de espécies reativas de oxigênio intracelular e apoptose de células da ilhota inibiu significativamente. Sugere-se que LMP pode ser utilizado como um reagente complementar para a diabetes a prevenção e terapia.


Assuntos
Polissacarídeos , Estresse Oxidativo , Cogumelos Shiitake , Micélio , Antioxidantes
6.
Braz. j. microbiol ; 47(3): 697-702, July-Sept. 2016. tab
Artigo em Inglês | LILACS | ID: lil-788971

RESUMO

ABSTRACT Dermatophytes are classified in three genera, Epidermophyton, Microsporum and Trichophyton. They have the capacity to invade keratinized tissue to produce a cutaneous infection known as dermatophytoses. This investigation was performed to study the effect of gaseous ozone and ozonized oil on three specific properties of six different dermatophytes. These properties included sporulation, mycelia leakage of sugar and nutrients and the activity of their hydrolytic enzymes. Generally, ozonized oil was found to be more efficacious than gaseous ozone. Microsporum gypseum and Microsporum canis were the most susceptible, while Trichophyton interdigitale and T. mentagrophytes were relatively resistant. The study revealed a steady decline in spore production of M. gypseum and M. canis on application of ozonated oil. An increase in leakage of electrolytes and sugar was noticed after treatment with ozonized oil in the case of M. gypseum, M. canis, T. interdigitale, T. mentagrophytes and T. rubrum. The results also revealed loss in urease, amylase, alkaline phosphatase, lipase and keratinase enzyme producing capacity of the investigated fungi.


Assuntos
Humanos , Ozônio/farmacologia , Arthrodermataceae/efeitos dos fármacos , Antifúngicos/farmacologia , Permeabilidade , Esporos Fúngicos/efeitos dos fármacos , Proteínas Fúngicas/metabolismo , Micélio , Arthrodermataceae/fisiologia , Eletrólitos/metabolismo , Ativação Enzimática , Metabolismo dos Carboidratos/efeitos dos fármacos
7.
Braz. j. microbiol ; 47(3): 658-664, July-Sept. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-788950

RESUMO

ABSTRACT Edible mushroom species are considered as an adequate source of food in a healthy diet due to high content of protein, fiber, vitamins, and a variety of minerals. The representatives of Pleurotus genus are characterized by distinct gastronomic, nutritional, and medicinal properties among the edible mushrooms commercialized worldwide. In the present study, the growth of mycelial biomass of Pleurotus albidus cultivated in submerged fermentation was evaluated. Saccharose, fructose, and maltose were the three main carbon sources for mycelial biomass formation with corresponding yields of 7.28 g L−1, 7.07 g L−1, and 6.99 g L−1. Inorganic nitrogen sources did not stimulate growth and the optimal yield was significantly higher with yeast extract (7.98 g L−1). The factorial design used to evaluate the influence of saccharose and yeast extract concentration, agitation speed, and initial pH indicated that all variables significantly influenced the production of biomass, especially the concentration of saccharose. The greater amount of saccharose resulted in the production of significantly more biomass. The highest mycelial biomass production (9.81 g L−1) was reached in the medium formulated with 30.0 g L−1 saccharose, 2.5 g L−1 yeast extract, pH 7.0, and a speed of agitation at 180 rpm. Furthermore, P. albidus manifested different aspects of morphology and physiology under the growth conditions employed. Media composition affected mycelial biomass production indicating that the diversification of carbon sources promoted its improvement and can be used as food or supplement.


Assuntos
Biomassa , Pleurotus/fisiologia , Micélio , Fermentação , Carbono/metabolismo , Pleurotus/ultraestrutura , Metabolismo dos Carboidratos , Nitrogênio/metabolismo
8.
Braz. j. microbiol ; 47(3): 775-780, July-Sept. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-788951

RESUMO

ABSTRACT Lectins are non-immunogenic carbohydrate-recognizing proteins that bind to glycoproteins, glycolipids, or polysaccharides with high affinity and exhibit remarkable ability to agglutinate erythrocytes and other cells. In the present study, ten Fusarium species previously not explored for lectins were screened for the presence of lectin activity. Mycelial extracts of F. fujikuroi, F. beomiformii, F. begoniae, F. nisikadoi, F. anthophilum, F. incarnatum, and F. tabacinum manifested agglutination of rabbit erythrocytes. Neuraminidase treatment of rabbit erythrocytes increased lectin titers of F. nisikadoi and F. tabacinum extracts, whereas the protease treatment resulted in a significant decline in agglutination by most of the lectins. Results of hapten inhibition studies demonstrated unique carbohydrate specificity of Fusarium lectins toward O-acetyl sialic acids. Activity of the majority of Fusarium lectins exhibited binding affinity to D-ribose, L-fucose, D-glucose, L-arabinose, D-mannitol, D-galactosamine hydrochloride, D-galacturonic acid, N-acetyl-d-galactosamine, N-acetyl-neuraminic acid, 2-deoxy-D-ribose, fetuin, asialofetuin, and bovine submaxillary mucin. Melibiose and N-glycolyl neuraminic acid did not inhibit the activity of any of the Fusarium lectins. Mycelial extracts of F. begoniae, F. nisikadoi, F. anthophilum, and F. incarnatum interacted with most of the carbohydrates tested. F. fujikuroi and F. anthophilum extracts displayed strong interaction with starch. The expression of lectin activity as a function of culture age was investigated. Most species displayed lectin activity on the 7th day of cultivation, and it varied with progressing of culture age.


Assuntos
Humanos , Animais , Micélio , Fusarium/metabolismo , Fusarium/química , Lectinas/metabolismo , Testes de Hemaglutinação , Eritrócitos/efeitos dos fármacos , Metabolismo dos Carboidratos , Fusarium/crescimento & desenvolvimento , Hemaglutinação , Lectinas/farmacologia
9.
Braz. j. microbiol ; 47(2): 468-479, Apr.-June 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-780832

RESUMO

Abstract Metabolites of mycoparasitic fungal species such as Trichoderma harzianum 88 have important biological roles. In this study, two new ketoacyl synthase (KS) fragments were isolated from cultured Trichoderma harzianum 88 mycelia using degenerate primers and analysed using a phylogenetic tree. The gene fragments were determined to be present as single copies in Trichoderma harzianum 88 through southern blot analysis using digoxigenin-labelled KS gene fragments as probes. The complete sequence analysis in formation of pksT-1 (5669 bp) and pksT-2 (7901 bp) suggests that pksT-1 exhibited features of a non-reducing type I fungal PKS, whereas pksT-2 exhibited features of a highly reducing type I fungal PKS. Reverse transcription polymerase chain reaction indicated that the isolated genes are differentially regulated in Trichoderma harzianum 88 during challenge with three fungal plant pathogens, which suggests that they participate in the response of Trichoderma harzianum 88 to fungal plant pathogens. Furthermore, disruption of the pksT-2 encoding ketosynthase–acyltransferase domains through Agrobacterium -mediated gene transformation indicated that pksT-2 is a key factor for conidial pigmentation in Trichoderma harzianum 88.


Assuntos
Trichoderma/enzimologia , Proteínas Fúngicas/metabolismo , Policetídeo Sintases/metabolismo , Doenças das Plantas/microbiologia , Trichoderma/classificação , Trichoderma/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/química , Dados de Sequência Molecular , Regulação Fúngica da Expressão Gênica , Alinhamento de Sequência , Sequência de Aminoácidos , Micélio/enzimologia , Micélio/genética , Policetídeo Sintases/genética , Policetídeo Sintases/química
10.
Braz. j. microbiol ; 46(4): 1053-1064, Oct.-Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-769641

RESUMO

Abstract This study investigated lytic enzyme activities in three indigenous Trichoderma strains namely, Trichoderma asperellum, Trichoderma harzianum and Trichoderma sp. Native Trichoderma strains and a virulent strain of Rhizoctonia solani isolated from infected bean plants were also included in the study. Enzyme activities were determined by measuring sugar reduction by dinitrosalicylic acid (DNS) method using suitable substrates. The antagonists were cultured in minimal salt medium with the following modifications: medium A (1 g of glucose), medium B (0.5 g of glucose + 0.5 g of deactivated R. solani mycelia), medium C (1.0 g of deactivated respective antagonist mycelium) and medium D (1 g of deactivated R. solani mycelia). T asperellum showed presence of higher amounts of chitinases, β-1, 3-glucanases and xylanases in extracellular protein extracts from medium D as compared to medium A. While, the higher activities of glucosidases and endoglucanses were shown in medium D extracts by T. harzianum. β-glucosidase activities were lower compared with other enzymes; however, activities of the extracts of medium D were significantly different. T. asperellum exhibited maximum inhibition (97.7%). On the other hand, Trichoderma sp. did not show any effect on mycelia growth of R. solani on crude extract.


Assuntos
Quitinases/análise , Quitinases/química , Quitinases/enzimologia , Quitinases/crescimento & desenvolvimento , Quitinases/metabolismo , /análise , /química , /enzimologia , /crescimento & desenvolvimento , /metabolismo , Proteínas Fúngicas/análise , Proteínas Fúngicas/química , Proteínas Fúngicas/enzimologia , Proteínas Fúngicas/crescimento & desenvolvimento , Proteínas Fúngicas/metabolismo , Glicosídeo Hidrolases/análise , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/enzimologia , Glicosídeo Hidrolases/crescimento & desenvolvimento , Glicosídeo Hidrolases/metabolismo , Micélio/análise , Micélio/química , Micélio/enzimologia , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Paquistão/análise , Paquistão/química , Paquistão/enzimologia , Paquistão/crescimento & desenvolvimento , Paquistão/metabolismo , Trichoderma/análise , Trichoderma/química , Trichoderma/enzimologia , Trichoderma/crescimento & desenvolvimento , Trichoderma/metabolismo
11.
Braz. j. microbiol ; 46(3): 937-941, July-Sept. 2015. ilus
Artigo em Inglês | LILACS | ID: lil-755825

RESUMO

In this study, we evaluated the effect of low and high molecular weight polycyclic aromatic hydrocarbons (PAHs), i.e., Phenanthrene, Pyrene and Benzo[a]pyrene, on the radial growth and morphology of the PAH-degrading fungal strains Aspergillus nomius H7 and Trichoderma asperellum H15. The presence of PAHs in solid medium produced significant detrimental effects on the radial growth of A. nomius H7 at 4,000 and 6,000 mg L−1 and changes in mycelium pigmentation, abundance and sporulation ability at 1,000–6,000 mg L−1. In contrast, the radial growth of T. asperellum H15 was not affected at any of the doses tested, although sporulation was observed only up to 4,000 mg L−1 and as with the H7 strain, some visible changes in sporulation patterns and mycelium pigmentation were observed. Our results suggest that fungal strains exposed to high doses of PAHs significantly vary in their growth rates and sporulation characteristics in response to the physiological and defense mechanisms that affect both pigment production and conidiation processes. This finding is relevant for obtaining a better understanding of fungal adaptation in PAH-polluted environments and for developing and implementing adequate strategies for the remediation of contaminated soils.

.


Assuntos
Aspergillus/crescimento & desenvolvimento , Benzo(a)pireno/farmacologia , Micélio/efeitos dos fármacos , Fenantrenos/farmacologia , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Pirenos/farmacologia , Esporos Fúngicos/efeitos dos fármacos , Trichoderma/crescimento & desenvolvimento , Aspergillus/efeitos dos fármacos , Aspergillus/metabolismo , Biodegradação Ambiental , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Microbiologia do Solo , Poluentes do Solo , Trichoderma/efeitos dos fármacos , Trichoderma/metabolismo
12.
Braz. j. microbiol ; 46(1): 67-74, 05/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-748229

RESUMO

Three non-ionic surfactants: Tween20, Tween80 and Breakthru® were screened for their effects on spore germination and mycelial growth rates and for their influence on three isolates of Beauveria bassiana spore germination at various temperatures. Tween20 and Tween80 were compatible with all the B. bassiana isolates in the germination studies, but inhibited germination at higher surfactant concentrations, irrespective of the conidial concentrations. Breakthru® had an inhibitory effect on germination even at the lowest concentration of 0.1% on all the B. bassiana isolates. The effects of the surfactants on spore germination did not correspond with their effects on colony growth. Conidial viability within the same formulation declined significantly with increases in temperature, irrespective of the surfactant. The optimal temperature for conidial germination of B. bassiana isolates was approximately 25 °C with an upper limit at 30 °C. Isolate 7320 was identified as the least affected by the different surfactants. This isolate was able to germinate rapidly in a broad temperature range of 25–30 °C after 24 h, this characteristic being an essential factor in controlling house fly populations in poultry houses.


Assuntos
Beauveria/crescimento & desenvolvimento , Beauveria/efeitos da radiação , Micélio/crescimento & desenvolvimento , Micélio/efeitos da radiação , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/efeitos da radiação , Tensoativos/metabolismo , Beauveria/efeitos dos fármacos , Micélio/efeitos dos fármacos , Esporos Fúngicos/efeitos dos fármacos , Temperatura
13.
Braz. j. microbiol ; 46(1): 195-200, 05/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-748254

RESUMO

Pleurotus ostreatus is able to bioaccumulate several metals in its cell structures; however, there are no reports on its capacity to bioaccumulate iron. The objective of this study was to evaluate cultivation variables to increase iron bioaccumulation in P. ostreatus mycelium. A full factorial design and a central composite design were utilized to evaluate the effect of the following variables: nitrogen and carbon sources, pH and iron concentration in the solid culture medium to produce iron bioaccumulated in mycelial biomass. The maximum production of P. ostreatus mycelial biomass was obtained with yeast extract at 2.96 g of nitrogen L−1 and glucose at 28.45 g L−1. The most important variable to bioaccumulation was the iron concentration in the cultivation medium. Iron concentration at 175 mg L−1 or higher in the culture medium strongly inhibits the mycelial growth. The highest iron concentration in the mycelium was 3500 mg kg−1 produced with iron addition of 300 mg L−1. The highest iron bioaccumulation in the mycelium was obtained in culture medium with 150 mg L−1 of iron. Iron bioaccumulation in P. ostreatus mycelium is a potential alternative to produce non-animal food sources of iron.


Assuntos
Ferro/metabolismo , Micélio/metabolismo , Pleurotus/metabolismo , Biomassa , Carbono/metabolismo , Meios de Cultura/química , Concentração de Íons de Hidrogênio , Micélio/crescimento & desenvolvimento , Nitrogênio/metabolismo , Pleurotus/crescimento & desenvolvimento
14.
São Paulo; s.n; 2015. 124 p. tab, ilus, graf.
Tese em Português | LILACS | ID: biblio-972069

RESUMO

A paracoccidioidomicose (PCM) é uma doença granulomatosa sistêmica, causada por Paracoccidioides spp., (P. brasiliensis e P. lutzii), geograficamente, limita-se a América Latina com as áreas endêmicas estendendo-se desde o México até a Argentina, constituindo uma das micoses sistêmicas de maior incidência na região, afetando principalmente trabalhadores rurais. O maior número de pacientes com PCM tem sido reportado principalmente no Brasil, Colômbia e Venezuela. A incidência real desta micose encontra-se subestimada no Brasil e pouco se conhece em relação a nova espécie descrita - P. lutzii. A maioria dos estudos em P. lutzii foram focados em genética, especiação e na geração de novos antígenos para melhorar a especificidade e sensibilidade dos testes sorológicos. Atualmente, as preparações antigênicas tradicionais, preparadas a partir de isolados de P. brasiliensis, são ineficientes. Raros são os trabalhos focados na biologia de P. lutzii e nos fatores de virulência que podem ser comparados com P. brasiliensis nos modelos experimentais. A nossa proposta de estudo foi avaliar alguns aspectos in vitro e in vivo relacionados com a patogenicidade e destacamos: a fagocitose e a morte intracelular de P. lutzii por macrófagos, peritoneais, de camundongos Knockouts (KO) e selvagens para PRRs (TLR2, TLR4 e Dectina) e ativadores intracelulares (MyD88 e NALP3). Paralelamente a este estudo, animais foram infectados com leveduras de P. lutzii e comparados com os modelos de infecção já estabelecidos com leveduras (Pb18) e conídios (ATCCPb60855) de P. brasiliensis. Nossos dados indicam que similar ao que ocorre com P. brasiliensis a fagocitose de P. lutzii depende de TLR2, TLR4 e Dectina- 1, resultados semelhantes também foram observadas na expressão de moléculas envolvidas na co-estimulação e a apresentação de antígenos (MHC II, CD80 e CD86)...


Paracoccidioidomycosis (PCM) is a systemic granulomatous disease caused by Paracoccidioides spp. (P. brasiliensis and P. lutzii), geographically, is limited to Latin America with endemic areas from Mexico to Argentina, as one of the systemic mycoses with the highest incidence in the region, mainly affecting rural workers. The largest number of patients with PCM has been mainly reported in Brazil, Colombia and Venezuela. The true incidence of this mycosis is underestimated in Brazil and little is known about the new species described - P. lutzii. Most studies in P. lutzii were focused on genetics, speciation and the generation of new antigens to improve the specificity and sensitivity of serological tests. Currently, traditional antigenic preparations, prepared with isolates of P. brasiliensis, are inefficient. There are few studies focused on P. lutzii biology and virulence factors that can be compared with P. brasiliensis in experimental models. Our study aimed to evaluate some in vitro and in vivo aspects related to pathogenicity: phagocytosis and intracellular killing of P. lutzii by peritoneal macrophages from knockouts (KO) for PRRs (TLR2, TLR4 and Dectin) and intracellular activators (MyD88 and NALP3). In addition, animals were infected with P. lutzii yeast and compared with the well-established models of infection with yeast cells (Pb18) and conidia (ATCC Pb60855) from P. brasiliensis. Our data indicate that similarly to what happens with the phagocytosis of P. brasiliensis, P. lutzii phagocytosis is dependent on TLR2, TLR4 and Dectin-1. Other molecules, involved in co-stimulation and presentation of antigens such as MHC II, CD80 and CD86 were also shown to participate in the P. lutzii-host interaction...


Assuntos
Masculino , Animais , Camundongos , Micologia , Paracoccidioides/imunologia , Paracoccidioidomicose , Esporos Fúngicos , Camundongos Knockout , Micélio , Leveduras
15.
Braz. j. microbiol ; 45(3): 861-872, July-Sept. 2014. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-727015

RESUMO

Two native Pleurotus spp. strains (white LB-050 and pale pink LB-051) were isolated from rotten tree trunks of cazahuate (Ipomoea murucoides) from the Mexican Mixtec Region. Both strains were chemically dedikaryotized to obtain their symmetrical monokaryotic components (neohaplonts). This was achieved employing homogenization time periods from 60 to 65 s, and 3 day incubation at 28 °C in a peptone-glucose solution (PGS). Pairing of compatible neohaplonts resulted in 56 hybrid strains which were classified into the four following hybrid types: (R1-n xB1-n, R1-n xB2-1, R2-n xB1-n and R2-n xB2-1). The mycelial growth of Pleurotus spp. monokaryotic and dikaryotic strains showed differences in texture (cottony or floccose), growth (scarce, regular or abundant), density (high, regular or low), and pigmentation (off-white, white or pale pink). To determine the rate and the amount of mycelium growth in malt extract agar at 28 °C, the diameter of the colony was measured every 24 h until the Petri dish was completely colonized. A linear model had the best fit to the mycelial growth kinetics. A direct relationship between mycelial morphology and growth rate was observed. Cottony mycelium presented significantly higher growth rates (p < 0.01) in comparison with floccose mycelium. Thus, mycelial morphology can be used as criterion to select which pairs must be used for optimizing compatible-mating studies. Hybrids resulting from cottony neohaplonts maintained the characteristically high growth rates of their parental strains with the hybrid R1-n xB1-n being faster than the latter.


Assuntos
Micélio/crescimento & desenvolvimento , Pleurotus/crescimento & desenvolvimento , Cruzamentos Genéticos , Meios de Cultura/química , México , Pigmentos Biológicos/metabolismo , Pleurotus/isolamento & purificação , Temperatura , Árvores/microbiologia
16.
Rev. Inst. Adolfo Lutz ; 73(2): 198-207, abr.-jun. 2014. tab, graf
Artigo em Português | LILACS, Sec. Est. Saúde SP | ID: lil-782603

RESUMO

O sistema de defesa antioxidante inibe ou reduz os danos causados às células pelas espécies reativas de oxigênio. Alguns compostos antioxidantes presentes na dieta auxiliam na defesa antioxidante do plasma. O potencial antioxidante do consumo oral de farinha produzida com micélio de Agaricus brasiliensis fermentado sobre grãos de trigo foi analisado nos plasmas de hamsters Golden Syrian machos hipercolesterolêmicos, que foram divididos em quatro grupos: P(dieta padrão), H (dieta hipercolesterolêmica padrão), C (dieta padrão + 10 % de farinha de trigo contendo micélio de A. brasiliensis), e HC (dieta hipercolesterolêmica padrão + 10 % de farinha de trigo contendo micélio deA. brasiliensis). Os animais foram alimentados durante 40 dias e depois sacrificados para coletar materiais biológicos.A análise da capacidade antioxidante mostrou que a dieta do grupo C induziu maior aumento significativo da concentração de antioxidantes no plasma (0,39 mg.mL-1, expresso em ácido ascórbico). O grupo HC apresentou maiorcapacidade antioxidante do que grupo H (p < 0,05), pois inibiu 20,2 % do branqueamento da crocina. O grupo H inibiu10,4 %, porém o grupo HC demonstrou capacidade antioxidante semelhante ao do grupo P (16,64 %). O consumo da farinha de trigo contendo micélio de A. brasiliensis estimulou a proteção antioxidante no plasma dos animais...


Assuntos
Humanos , Agaricus , Antioxidantes , Espectrofotômetros , Farinha , Hipercolesterolemia , Micélio , Triticum , Cricetinae
17.
Rev. Inst. Adolfo Lutz ; 73(2): 198-207, abr.-jun. 2014. tab, graf
Artigo em Português | LILACS, SESSP-CTDPROD, Sec. Est. Saúde SP, SESSP-ACVSES, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: lil-764782

RESUMO

O sistema de defesa antioxidante inibe ou reduz os danos causados às células pelas espécies reativas de oxigênio. Alguns compostos antioxidantes presentes na dieta auxiliam na defesa antioxidante do plasma. O potencial antioxidante do consumo oral de farinha produzida com micélio de Agaricus brasiliensis fermentado sobre grãos de trigo foi analisado nos plasmas de hamsters Golden Syrian machos hipercolesterolêmicos, que foram divididos em quatro grupos: P(dieta padrão), H (dieta hipercolesterolêmica padrão), C (dieta padrão + 10 % de farinha de trigo contendo micélio de A. brasiliensis), e HC (dieta hipercolesterolêmica padrão + 10 % de farinha de trigo contendo micélio deA. brasiliensis). Os animais foram alimentados durante 40 dias e depois sacrificados para coletar materiais biológicos.A análise da capacidade antioxidante mostrou que a dieta do grupo C induziu maior aumento significativo da concentração de antioxidantes no plasma (0,39 mg.mL-1, expresso em ácido ascórbico). O grupo HC apresentou maiorcapacidade antioxidante do que grupo H (p < 0,05), pois inibiu 20,2 % do branqueamento da crocina. O grupo H inibiu10,4 %, porém o grupo HC demonstrou capacidade antioxidante semelhante ao do grupo P (16,64 %). O consumo da farinha de trigo contendo micélio de A. brasiliensis estimulou a proteção antioxidante no plasma dos animais.


The main function of antioxidant defense system is to inhibit or reduce the cells damage caused by reactive oxygenspecies. Some antioxidants occurring in the diet enhance the antioxidant defense of plasma. The antioxidant potentialof oral intake of a flour produced with A. brasiliensis mycelium fermented on wheat grains was evaluated in plasmasamples from male hypercholesterolemic Syrian Golden hamsters, were divided into four groups: P (standard diet), H(standard hypercholesterolemic diet), C (standard diet + 10 % of wheat flour containing mycelium of A. brasiliensis),and HC (standard diet hypercholesterolemic + 10 % wheat flour containing mycelium of A. brasiliensis). The animalswere fed for 40 days and then sacrificed for collecting plasma. The antioxidant capacity analysis showed that the dietaryintake of group C induced the most significant increase of antioxidants concentrations in plasmas (0.39 mg.mL-1,expressed in ascorbic acid). The HC group showed higher antioxidant capacity than the H group (p < 0.05), as itinhibited 20.2 % of crocin bleaching, while the H group inhibited 10.4 % only; however the HC group showed a similarantioxidant capacity of P group (16.64 %). It is suggested that the consumption of wheat flour containing mycelium ofA. brasiliensis induced the antioxidant protection in animals plasma.


Assuntos
Agaricus , Antioxidantes , Farinha , Hipercolesterolemia , Micélio , Espectrofotômetros , Triticum , Cricetinae
18.
Arq. ciênc. vet. zool. UNIPAR ; 17(4): 249-252, out.-dez.2014. tab
Artigo em Português | LILACS | ID: lil-758596

RESUMO

Fungos basidiomicetos têm a capacidade de bioacumular metais pesados, no entanto existem poucos trabalhos sobre bioacumulação de zinco em micélio de Agaricussubrufescens. O objetivo deste trabalho foi avaliar a bioacumulação de zinco em micélio vegetativo de A. subrufescens cultivado em meio sólido e líquido. O fungo foi crescido em meio sólido ou em meio líquido a base de extrato de malte adicionado de ZnSO4 a fim de obter zero; 2,5; 5; 7,5; 10; 15 ou 20 ppm de zinco. Os meios foram inoculados e após 14 dias foi determinada a biomassa e a bioacumulação de zinco. A adição de zinco no meio de cultivo inibiu o crescimento micelial e induziu a bioacumulação na biomassa tanto no cultivo sólido como no líquido. Adições acima de 7,5 ppm de zinco inibiram totalmente o crescimento micelial. O fungo crescido em meio de cultivo líquido sofre maior inibição do crescimento com a adição de zinco e maior bioacumulação que no meio sólido...


Fungi basidiomycetes have the ability to bioaccumulate heavy metals, but there are few studies on zinc bioaccumulation in the mycelium of Agaricus subrufescens. The objective of this study is to evaluate the zinc bioaccumulation in the mycelium of A. subrufescens cultivated in solid and liquid culture media. Mycelium was grown on solid or liquid medium in malt extract base added with ZnSO4 to obtain zero, 2.5, 5, 7.5, 10, 15 or 20-ppm zinc. Mycelial biomass and zinc bioaccumulation were determined 14 days after inoculation in the culture media. Addition of zinc in culture medium inhibited mycelial growth and induced biomass bioaccumulation both in solid and in liquid culture. Additions higher than 7.5-ppm zinc completely inhibited mycelial growth in culture medium. Mycelial growth in liquid culture presented greater increase of growth inhibition with the addition of zinc and greater bioaccumulation than in solid medium...


Hongos basidiomicetos tienen la capacidad de bioacumular metales pesados, sin embargo hay pocos estudios sobre la bioacumulación de zinc en el micelio de Agaricus subrufescens. El objetivo de este estudio ha sido evaluar la bioacumulación de zinc en el micelio de A. subrufescens cultivado en medio sólido y líquido. El hongo ha crecido en medio sólido o líquido a base de extracto de malta agregado de ZnSO4 para obtener cero; 2.5, 5, 7.5, 10, 15 o 20 ppm de zinc. Los medios fueron inoculados y después de 14 días se determinó la biomasa y la bioacumulación de zinc. La adición de zinc en el medio del cultivo inhibió el crecimiento micelial y indujo la bioacumulación de la biomasa tanto en el cultivo sólido como en el líquido. Adiciones superiores a 7.5 ppm de zinc inhibieron completamente el crecimiento del micelio. El hongo crecido en medio de cultivo líquido sufre mayor inhibición del crecimiento con la adición de zinc y mayor bioacumulación que en el medio sólido...


Assuntos
Animais , Bioacumulação/análise , Bioacumulação/classificação , Micélio/enzimologia , Micélio/química , Zinco/análise , Zinco/química
19.
Biosci. j. (Online) ; 29(4): 787-795, july/aug. 2013. tab
Artigo em Português | LILACS | ID: biblio-914661

RESUMO

A aplicação de fungicidas nos órgãos aéreos é estratégia de controle para mancha-de-macrospora causada pelo fungo Stenocarpella macrospora. O objetivo do trabalho foi determinar a sensibilidade de S. macrospora a fungicidas pela inibição do crescimento do micélio (CM) e germinação de conídios (GC). Foram avaliados 12 fungicidas pertencentes aos grupos químicos dos benzimidazóis, estrobilurinas e triazóis, seis concentrações e dois isolados do fungo (SC e MT). Os fungicidas foram diluídos em água destilada e esterilizada e adicionados ao meio de cultura de batata-dextrose-ágar (micélio) e ágar-água (conídios) após a esterilização. A porcentagem de inibição do CM e GC foi calculada em relação à testemunha, estimando-se valores de concentração inibitória de 50% (CI50). Constatou-se que os fungicidas testados foram altamente fungitóxicos na inibição do CM, sendo que a CI50 foi menor que 1 ppm para todos os fungicidas, não havendo diferença entre isolados. Na inibição da GC, as estrobilurinas apresentaram maior fungitoxicidade, pois a CI50 ficou entre 0,0035 e 0,03 ppm, sendo o isolado SC mais sensível aos fungicidas. Os valores de CI50 para os diferentes fungicidas específicos para S. macrospora são úteis no monitoramento da sensibilidade do fungo em regiões com demanda intensa de fungicidas no milho.


The application of fungicides in the aerial organs is control strategy to macrospora spot caused by fungus Stenocarpella macrospora. The objective of this study was to determine the sensitivity of S. macrospora to fungicides by inhibition of mycelial growth (MG) and conidial germination (CG). It was evaluated 12 fungicides belonging to the chemical groups of the benzimidazoles, triazoles and strobilurins, six concentrations and two isolates of the fungus (SC and MT). The fungicides were diluted in sterile distilled water and added to the culture medium of potato dextrose agar (mycelium) and water-agar (spore) after sterilization. The percentage of inhibition of MC and CG was calculed in comparison with control, estimating of 50% inhibitory concentration (IC50). The fungicides tested were effective in inhibiting the MC. The IC50 was less than 1 ppm for all fungicides. There was no difference between isolates. The inhibition of CG had higher fungitoxicity strobilurins, and the IC50 was between 0.0035 and 0.03 ppm, and the isolated SC showed the higher sensitivity to the fungicides. The IC50 values obtained for fungicides and specific S.


Assuntos
Esporos Fúngicos , Zea mays , Micélio , Fungos , Fungicidas Industriais , Fungicidas Industriais/toxicidade
20.
Braz. j. microbiol ; 44(1): 215-223, 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-676896

RESUMO

The present work was aimed at optimizing a culture medium for biomass production and phenolic compounds by using Ganoderma lucidum. The culture was optimized in two stages; a Plackett-Burman design was used in the first one for identifying key components in the medium and a central composite design was used in the second one for optimizing their concentration. Both responses (biomass and phenolic compounds) were simultaneously optimized by the latter methodology regarding desirability, and the optimal concentrations obtained were 50.00 g/L sucrose, 13.29 g/L yeast extract and 2.99 g/L olive oil. Maximum biomass production identified in these optimal conditions was 9.5 g/L and that for phenolic compounds was 0.0452 g/L, this being 100% better than that obtained in the media usually used in the laboratory. Similar patterns regarding chemical characterization and biological activity towards Aspergillus sp., from both fruiting body and mycelium-derived secondary metabolites and extracts obtained in the proposed medium were observed. It was shown that such statistical methodologies are useful for optimizing fermentation and, in the specific case of G. lucidum, optimizing processes for its production and its metabolites in submerged culture as an alternative to traditional culture.


Assuntos
Biomassa , Compostos Fenólicos/análise , Meios de Cultura/análise , Micélio/isolamento & purificação , Reishi/isolamento & purificação , Metodologia , Otimização , Técnicas
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