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Ergosterol contents in mycorrhizal wild edible mushrooms: comparison by hierarchical cluster analysis

Barreira, João C.M.; Martins, Anabela; Ferreira, Isabel C.F.R.
Fonte: Instituto Politécnico de Bragança Publicador: Instituto Politécnico de Bragança
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
37.28%
Sterols are important molecules of the unsaponifiable fraction in several matrices. In mushrooms, ergosterol, which is an important vitamin D2 precursor, is clearly the main sterol. Hierarchical cluster analysis (HCA) is an unsupervised learning method to standardized data, checking for similarities between sample groups. This method calculates the distances (or correlation) between all samples using a defined metric such as squared Euclidean distance or Chebychev distance. Hierarchical clustering is the most common approach in which clusters are formed sequentially. The most similar objects are first grouped, and these initial groups are merged according to their similarities. Eventually as the similarity decreases all subgroups are fused into a single cluster. Herein, ergosterol was quantified by high performance liquid chromatography, coupled with an ultraviolet detector, in some of the most appreciated mycorrhizal edible mushrooms (Amanita caesarea, Boletus edulis, Cantharellus cibarius, Lactarius deliciosus and Morchella esculenta). Considering fat content (percentage) and ergosterol contents in mg/g fat and mg/100 g of dry weight, two main groups were formed in the HCA: one aggregating A. caesarea and B. edulis and another constituted by C. cibarius...

Development of a novel methodology for the analysis of ergosterol in mushrooms

Barreira, João C.M.; Oliveira, M.B.P.P.; Ferreira, Isabel C.F.R.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.42%
Sterols are important molecules in the unsaponifiable fraction of several matrices. Ergosterol, which is an important vitamin D2 precursor, is clearly the main sterol in mushrooms. Herein, an analytical method for ergosterol determination in cultivated and wild mushrooms was developed using high-performance liquid chromatography coupled to ultraviolet detection. The chromatographic separation was achieved in an Inertsil 100A ODS-3 reversed-phase column using an isocratic elution with acetonitrile/methanol (70:30, v/v) at a flow rate of 1 mL/min. Different extraction methodologies were tested, using n-hexane, methanol/dichloromethane (75:25, v/v) or chloroform/methanol (20:10, v/v). The method was optimised using Fistulina hepatica and proved to be reproductive and accurate. Ergosterol was the most abundant sterol by a greater extent in all mushrooms. In general, the cultivated species showed higher contents, mainly Agaricus bisporus and Lentinus edodes. Among wild species, Boletus edulis was the mushroom with the highest content in ergosterol. Results were expressed in fat content, dry weight and fresh weight bases. The assessment of ergosterol amounts might be very useful due to the bioactive potential that has been attributed to this molecule and its derivatives.

Quantificação do teor de ergosterol por HPLC-UV e determinação da actividade antioxidante no cogumelo Pleurotus ostreatus comercializado e cultivado em borras de café e palha de trigo

Ricardo, Sofia Cristina Nunes
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Dissertação de Mestrado
POR
Relevância na Pesquisa
37.66%
Os cogumelos comestíveis são apreciados em todo o mundo não só pela sua textura e sabor, mas também pelas suas propriedades nutricionais e funcionais. Estas propriedades devem-se ao facto dos cogumelos possuírem compostos bioactivos, nomeadamente, ergosterol (precursor da vitamina D2), compostos fenólicos, tocoferóis, ácido ascórbico e carotenóides, responsáveis pela actividade antioxidante, pelo que podem ser associados à promoção da saúde. Um dos cogumelos comestíveis que tem suscitado maior interesse nos últimos anos é o Pleurotus ostreatus, conhecido como cogumelo ostra, devido à facilidade de cultivo e ao seu grande potencial económico e qualidade nutricional. Existe, assim, a necessidade de estudar o seu índice qualitativo e quantitativo de nutrientes e de compostos bioactivos por forma a sobrevalorizar o seu cultivo. Este estudo tem por objectivo centrar-se, fundamentalmente, na quantificação do teor de ergosterol por HPLC-UV (Cromatografia Líquida de Alta Eficiência – detector UV-Vis) e na determinação da actividade antioxidante pelo método da actividade captadora do radical livre DPPH• (2,2-difenil-1-picril-hidrazilo) do cogumelo Pleurotus ostreatus cultivado em diferentes substratos, nomeadamente...

Identificação e caracterização cromossomal de 9 loci de Leishmania (L.) major relacionados com resistência a inibidores da via de biossíntese do ergosterol; Identification and chromosomal localization of 9 Leishmania (L.) major loci related to resistance against two inhibitors of ergosterol biosynthesis pathway

Camizotti, Luciana Aparecida
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 17/12/2008 PT
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37.53%
O ergosterol é um componente responsável por manter a integridade e a fluidez das membranas de Leishmania spp. A partir de uma metodologia que consiste em seleção por superexpressão gênica, foram isolados nove diferentes loci de L. (L.) major relacionados com a resistência a dois inibidores da via de biossíntese do ergosterol: Terbinafina (TBF) e Itraconazol (ITZ). Análises funcionais individuais desses nove loci na presença de TBF e ITZ (ou do análogo Cetoconazol - CTZ) apresentaram níveis significantes de resistência após transfecção em células selvagens de L. (L.) major. Nesse trabalho apresentamos a metodologia de isolamento de um desses loci (cItz2), bem como a análise in silico das regiões cromossômicas correspondentes aos insertos dos nove cosmídios no genoma de L. (L.) major; Ergosterol is an important compound responsible to maintain integrity and fluidity of Leishmania spp. membranes. Starting from an overexpression/selection method, our group has isolated nine different loci of L. (L.) major related to resistance against two inhibitors of the ergosterol biosynthesis pathway, Terbinafine (TBF) and Itraconazole (ITZ). Individual functional analysis of these nine loci in the presence of TBF and/or ITZ (or the ITZ analog Ketoconazole...

Effect of culture conditions on the biomass determination by ergosterol of Lentinus crinitus and Psilocybe castanella

Silva, Ricardo Ribeiro; Corso, Carlos Renato; Matheus, Dacio Roberto
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 841-846
ENG
Relevância na Pesquisa
37.5%
Estimating fungal growth is important in processes of soil bioremediation. It has been demonstrated that ergosterol is a good indicator of fungal biomass in solid substrata. In the present study were evaluated the effects upon the ergosterol rate of Lentinus crinitus Berk. and Psilocybe castanella Peck through the culture conditions of these fungi, which are evaluated for the bioremediation of soils contaminated by organochlorates. A good correlation between fungal biomass and ergosterol was observed for both species. The culture conditions did not influence the ergosterol rate of L. crinitus. Yet the ergosterol rate of P. castanella was influenced from 35 days of culture and when grown in the presence of 15.00 g hexachlorobenzene l(-1) of culture medium. So it is possible to estimate growth of both species using ergosterol as indicator in processes of soil bioremediation since the influences observed in the ergosterol rate of P. castanella are considered.

Isolation of ergosterol peroxide and its reversion to ergosterol in the pathogenic fungus Sporothrix schenckii

Da Graça Sgarbi, Diana Bridon; Da Silva, Antonio Jorge Ribeiro; Carlos, Iracilda Zeppone; Silva, Célio Lopes; Angluster, Jayme; Alviano, Celuta Sales
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 9-14
ENG
Relevância na Pesquisa
37.5%
Ergosterol peroxide, a presumed product of the H2O2-dependent enzymatic oxidation of ergosterol, has been isolated from yeast from yeast forms of the pathogenic fungus Sporothrix schenckii. The substance, which may have a role in fungal virulence, has been characterized mainly using spectroscopic methods (1H and 13C nuclear magnetic resonance and high resolution mass spectra). The purified compound showed a molecular formula of C28H44O3, displaying characteristic features of epidioxy sterols and was reverted to ergosterol when submitted to S. schenckii enzymatic extract.

Ergosterol analyses of oil palm seedlings and plants infected with Ganoderma

Mohd As wad, A. B.; Sariah, M.; Paterson, R. R. M.; Zainal Abidin, M. A.; Lima, Nelson
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /11/2011 ENG
Relevância na Pesquisa
37.42%
Basal stem rot of oil palm (OP) by Ganoderma boninense is of major economic concern and it is the predominant disease of OP in SE Asia. Also, other plantation crops are affected by Ganoderma. The early detection of symptoms is crucial for control, although effective methods remain elusive. Ergosterol is the principal sterol of fungi and plays an essential role in the cell membrane and other cellular constituents. The analysis of ergosterol is useful for fungal detection in solid plant substrates. The present report compares ergosterol concentration in sound and decayed OP seedlings and mature plants using HPLC with diode array detection. The disease of OP requires to be considered as a white rot process where fungal biomass will increase from a low to high level as the infection progresses. G. boninense biomass was correlated with ergosterol concentration in vitro. Furthermore, the sterol was correlated with internal colonization (a) of inoculated seedlings, (b) of felled and standing OP and (c) to external symptoms of the disease. The compound was not detected in healthy samples. Disease treatments may be made more effective as the amounts of fungal biomass can be estimated and early detection is possible. Ergosterol quantification is a provisional diagnostic method for detection for G. boninense infection in OP which can be employed with other methods...

Rapid detection of Ganoderma-infected oil palms by microwave ergosterol extraction with HPLC and TLC

Muniroh, M. S.; Sariah, M.; Abidin, M. A. Zainal; Lima, Nelson; Paterson, R. R. M.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2014 ENG
Relevância na Pesquisa
37.36%
Detection of basal stem rot (BSR) by Ganoderma of oil palms was based on foliar symptoms and production of basidiomata. Enzyme-Linked Immunosorbent Assays-Polyclonal Antibody (ELISA-PAB) and PCR have been proposed as early detection methods for the disease. These techniques are complex, time consuming and have accuracy limitations. An ergosterol method was developed which correlated well with the degree of infection in oil palms, including samples growing in plantations. However, the method was capable of being optimised. This current study was designed to develop a simpler, more rapid and efficient ergosterol method with utility in the field that involved the use of microwave extraction. The optimised procedure involved extracting a small amount of Ganoderma, or Ganoderma-infected oil palm suspended in low volumes of solvent followed by irradiation in a conventional microwave oven at 70 °C and medium high power for 30 s, resulting in simultaneous extraction and saponification. Ergosterol was detected by thin layer chromatography (TLC) and quantified using high performance liquid chromatography with diode array detection. The TLC method was novel and provided a simple, inexpensive method with utility in the field. The new method was particularly effective at extracting high yields of ergosterol from infected oil palm and enables rapid analysis of field samples on site...

Estudos biofísicos em sistemas modelo da membrana plasmática da levedura

Cordeiro, André Miguel Henriques
Fonte: Universidade de Lisboa Publicador: Universidade de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2009 POR
Relevância na Pesquisa
27.58%
Tese de mestrado, Bioquímica (Bioquímica Médica), Universidade de Lisboa, Faculdade de Ciências, 2009; Na membrana plasmatica de Saccharomyces cerevisiae já foram identificados domínios lipídicos compostas maioritariamente por esteróis e/ou esfingolípidos, podendo apresentar-se organizadas duma forma semelhante a uma fase líquido ordenado (lo). No entanto, os princípios biofísicos da formação e funcionamento desses domínios ainda nao são totalmente conhecidos. Neste trabalho foram utilizadas técnicas de espectroscopia de fluorescência em estado estacionário e resolvidas no tempo para caracterizar propriedades biofísicas de diversas misturas lipídicas que mimetizam os domínios da membrana plasmática da levedura, de modo a esclarecer aqueles princípios. Foram estudados os sistemas binários 1-Palmitoil-2-oleoil-sn-glicero-3- fosfocolina (POPC)/ ergosterol e POPC/ fitoceramida, que mimetizam o papel dos esteróis e esfingolípidos na formação de domínios, respectivamente, com as sondas ácido trans-parinárico (t-PnA) e difenil-hexatrieno (DPH). Confirmou-se a formação de uma fase lo induzida pelo ergosterol, de acordo com resultados da literatura, ao passo que a fitoceramida a baixas concentrações tem a capacidade de induzir a formação de fases gel de elevada rigidez. Neste trabalho é proposto um diagrama de fases do tipo peritéctico para o sistema POPC/fitoceramida (C18:0)...

Can Ergosterol Be an Indicator of Fusarium Fungi and Mycotoxins in Cereal Products?

Stanisz,Ewa; Zgoła-Grześkowiak,Agnieszka; Waśkiewicz,Agnieszka; Stępień,Łukasz; Beszterda,Monika
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2015 EN
Relevância na Pesquisa
37.36%
Presence of fungi in food and feed products is a major problem. Fungi synthesize a large number of secondary metabolites including particularly harmful mycotoxins. They can be produced in plant tissues and are commonly found all over the world in many products including cereals. A total of 44 samples were taken for identification of ergosterol - the potential marker of fungal presence. Fourteen of these samples were chosen for further studies that included the evaluation of the relationship between ergosterol content and three major mycotoxins produced by Fusariumspp.: fumonisin B1, zearalenone and deoxynivalenol. Fungal strains were also isolated and identified by molecular means in those samples. The results of the studies give a further and more detailed insight into the relationship between contents of ergosterol and mycotoxins in different cereal products. It was found that there was no correlation between content of ergosterol and mycotoxins in the tested food products. Also, the presence of mycotoxins was not correlated with occurrence of species able to produce these toxins.

Uso do fungo Fusarium oxysporum como indicador de ametrina, através da medida de biomassa, pela quantificação do ergosterol

Galvão,José Geraldo; Guerreiro,Mário César; Souza,Josefina Aparecida de; Coura,Samuel Martins da Costa
Fonte: Editora da Universidade Federal de Lavras Publicador: Editora da Universidade Federal de Lavras
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2003 PT
Relevância na Pesquisa
37.28%
Neste trabalho avaliou-se o fungo Fusarium oxysporum como potencial bioindicador de contaminação de herbicida da classe das triazinas, por meio do monitoramento do crescimento fúngico. Para tanto, foi avaliado o crescimento micelial em meio de cultura extrato malte e ágar na presença do herbicida ametrina, em diversas concentrações. O crescimento micelial foi avaliado pela determinação do teor de ergosterol, por CLAE/DAD, em comprimento de onda de 281 nm. A quantificação do ergosterol passa pelas etapas de extração em etanol, saponificação em base forte, fracionamento em hexano:água (4:1) e análise por CLAE. O crescimento do fungo foi retardado pelo aumento da concentração do herbicida, mostrando que o potencial dessa técnica de avaliação de contaminação por ametrina. O ergosterol mostrou ser um bom indicador de biomassa fúngica metabólicamente ativa.

The relationship between fungi growth and aflatoxin production with ergosterol content of corn grains

Castro,Maria Fernanda Penteado Moretzsohn de; Bragagnolo,Neura; Valentini,Sílvia Regina de Toledo
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2002 EN
Relevância na Pesquisa
37.59%
The relationships between fungal growth and ergosterol content and between aflatoxins B1 and B2 production and ergosterol content were verified in corn grains. In the first experiment, fungal growth and ergosterol content were monitored during incubation of corn grains presenting water activities of 0.85a w and 0.92a w at 25ºC over a period of 18 days. For the Taiúba variety, the fungi growth and ergosterol content increased more rapidly for 0.92a w than 0.85a w. Maximum ergosterol levels were 2.8 and 4.6 µg/g, respectively, for 0.85a w and 0.92a w. For the Cargill hybrid 606, a more pronounced increase in fungal growth was verified just at the end of the incubation period, mainly for 0.92a w when an acentuated increase in ergosterol content was also observed. Maximum ergosterol levels detected were 1.6 µg/g and 5.8 µg/g, respectively, for 0.85a w and 0.92a w. There was a significant correlation between ergosterol content and log of CFU g-1 for 0.92a w but not for 0.85 a w. In the second experiment, samples of corn grains of the Taiúba variety at 0.87a w and 0.95a w were inoculated with a toxigenic Aspergillus flavus strain and incubated at 25ºC. Ergosterol levels reached maximum values of 12.1 and 73.4 µg/g, respectively, for 0.87a w and 0.95a w. In both water activities...

Quantitation of Ergosterol Content: Novel Method for Determination of Fluconazole Susceptibility of Candida albicans

Arthington-Skaggs, Beth A.; Jradi, Hoda; Desai, Tejal; Morrison, Christine J.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /10/1999 EN
Relevância na Pesquisa
27.53%
MIC end points for the most commonly prescribed azole antifungal drug, fluconazole, can be difficult to determine because its fungistatic nature can lead to excessive “trailing” of growth during susceptibility testing by National Committee for Clinical Laboratory Standards broth macrodilution and microdilution methods. To overcome this ambiguity, and because fluconazole acts by inhibiting ergosterol biosynthesis, we developed a novel method to differentiate fluconazole-susceptible from fluconazole-resistant isolates by quantitating ergosterol production in cells grown in 0, 1, 4, 16, or 64 μg of fluconazole per ml. Ergosterol was isolated from whole yeast cells by saponification, followed by extraction of nonsaponifiable lipids with heptane. Ergosterol was identified by its unique spectrophotometric absorbance profile between 240 and 300 nm. We used this sterol quantitation method (SQM) to test 38 isolates with broth microdilution end points of ≤8 μg/ml (susceptible), 16 to 32 μg/ml (susceptible dose-dependent [SDD]), or ≥64 μg/ml (resistant) and 10 isolates with trailing end points by the broth microdilution method. No significant differences in mean ergosterol content were observed between any of the isolates grown in the absence of fluconazole. However...

Ergosterol Content in Various Fungal Species and Biocontaminated Building Materials

Pasanen, Anna-Liisa; Yli-Pietilä, Kati; Pasanen, Pertti; Kalliokoski, Pentti; Tarhanen, Juhani
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /01/1999 EN
Relevância na Pesquisa
27.53%
This paper reports the ergosterol content for microbial cultures of six filamentous fungi, three yeast species, and one actinomycete and the ergosterol levels in 40 samples of building materials (wood chip, gypsum board, and glass wool) contaminated by microorganisms. The samples were hydrolyzed in alkaline methanol, and sterols were silylated and analyzed by gas chromatography-mass spectrometry. The average ergosterol content varied widely among the fungal species over the range of 2.6 to 42 μg/ml of dry mass or 0.00011 to 17 pg/spore or cell. Ergosterol could not be detected in the actinomycete culture. The results for both the fungal cultures and building material samples supported the idea that the ergosterol content reflects the concentration of filamentous fungi but it underestimates the occurrence of yeast cells. The ergosterol content in building material samples ranged from 0.017 to 68 μg/g of dry mass of material. A good agreement between the ergosterol concentration and viable fungal concentrations was detected in the wood chip (r > 0.66, P ≤ 0.009) and gypsum board samples (r > 0.48, P ≤ 0.059), whereas no relationship between these factors was observed in the glass wool samples. For the pooled data of the building materials...

Effect of Culture Conditions on Ergosterol as an Indicator of Biomass in the Aquatic Hyphomycetes

Charcosset, Jean-Yves; Chauvet, Eric
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/2001 EN
Relevância na Pesquisa
27.58%
Ergosterol is a membrane component specific to fungi that can be used to estimate fungal biomass using appropriate factors of conversion. Our objectives were to determine the limits of use of ergosterol content as a measure of biomass for aquatic hyphomycetes, and to evaluate a previously established ergosterol-to-biomass conversion factor. We varied inoculum quality, growth medium, and degree of shaking of four aquatic hyphomycete species. In cultures inoculated with homogenized mycelium, we found a significant effect of shaking condition and culture age on ergosterol content. In liquid cultures with defined medium, ergosterol content reached 10 to 11 μg/mg of mycelium (dry mass) and varied by factors of 2.2 during exponential growth and 1.3 during stationary phase. The increase in ergosterol content during exponential phase could be attributed, at least in part, to rapid depletion of glucose. Oxygen availability to internal hyphae within the mycelial mass is also responsible for the differences found between culture conditions. Ergosterol concentration ranged from 0.8 to 1.6 μg/mg in static cultures inoculated with agar plugs. Ergosterol content varied by a factor of 4 in two media of different richnesses. For different combinations of these parameters...

Use of Solid-Phase Extraction To Determine Ergosterol Concentrations in Plant Tissue Colonized by Fungi

Gessner, M. O.; Schmitt, A. L.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/1996 EN
Relevância na Pesquisa
27.58%
At present, the ergosterol and acetate-to-ergosterol techniques are generally considered to be the methods of choice to quantify fungal biomass, growth rate, and productivity under natural conditions. Both methods rely on the accurate isolation and quantification of ergosterol, a major membrane component of eumycotic fungi. Taking advantage of the solid-phase extraction (SPE) technique, we present a novel method to determine the ergosterol concentration in lipid extracts derived from plant tissues and dead organic matter colonized by fungi. In this method, a primary alkaline extract is acidified and passed through a reversed-phase (C(inf18)) SPE column. The column is then washed with an alkaline methanol-water solution to eliminate interfering substances and increase pH and is thoroughly dried in air. Ergosterol is eluted with alkaline isopropanol. This eluting solvent was chosen to produce a strongly basic pH of the final extract and thus confer stability on the ergosterol molecule before high-performance liquid chromatography analysis. The recovery of ergosterol from plant tissues and the O(infhf) horizon of a woodland soil ranged from 85 to 98%, and the overall extraction efficiency was similar to that obtained by a conventional procedure involving liquid-liquid extraction. Potential pitfalls of ergosterol analysis by SPE include (i) insufficient acidification before sample loading on the extraction column...

Using ergosterol to mitigate the deleterious effects of ethanol on bilayer structure

Dickey, Allison N.; Yim, Wen-Sau; Faller, Roland
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 26/02/2009 EN
Relevância na Pesquisa
27.59%
In wine fermentations, yeast is exposed to concentrated ethanol solutions. Ergosterol, a sterol that is found in lower eukaryotic membranes, helps preserve the structural integrity of yeast membranes in stressful environmental conditions. A premature arrest in ethanol production due to unknown metabolic changes in yeasts results in undesirably large concentrations of residual sugar and may be caused by the formation of an ethanol-induced interdigitated phase. We use atomistic Molecular Dynamics simulations to examine the induction of the interdigitated phase in model yeast membranes that contain either 0, 10, 20, 25 mol% ergosterol in ethanol concentrations of 0, 10, 15 vol%. The 25 mol% ergosterol system shows a similar level of interdigitation for the 0 and 10 vol% ethanol solutions, indicating that ergosterol molecules in this system are able to effectively counteract the disruptive behavior of ethanol molecules. However, at a 15 vol% ethanol solution, the amount of interdigitation triples and this ethanol concentration is similar to the concentrations found in stuck fermentations. The other three ergosterol concentrations studied (0, 10, 20 mol%) show larger quantities of interdigitation in the 10 vol% ethanol solution than the 0 vol% solution. Thus...

Uso do fungo Fusarium oxysporum como indicador de ametrina, através da medida de biomassa, pela quantificação do ergosterol

Fonte: Editora da Universidade Federal de Lavras Publicador: Editora da Universidade Federal de Lavras
Tipo: Artigo de Revista Científica Formato: text/html
PT
Relevância na Pesquisa
37.28%
Neste trabalho avaliou-se o fungo Fusarium oxysporum como potencial bioindicador de contaminação de herbicida da classe das triazinas, por meio do monitoramento do crescimento fúngico. Para tanto, foi avaliado o crescimento micelial em meio de cultura extrato malte e ágar na presença do herbicida ametrina, em diversas concentrações. O crescimento micelial foi avaliado pela determinação do teor de ergosterol, por CLAE/DAD, em comprimento de onda de 281 nm. A quantificação do ergosterol passa pelas etapas de extração em etanol, saponificação em base forte, fracionamento em hexano:água (4:1) e análise por CLAE. O crescimento do fungo foi retardado pelo aumento da concentração do herbicida, mostrando que o potencial dessa técnica de avaliação de contaminação por ametrina. O ergosterol mostrou ser um bom indicador de biomassa fúngica metabólicamente ativa.

Optimization of ultrasound assisted extraction of ergosterol from Agaricus bisporus L

Heleno, Sandrina A.; Diz, Patricia; Barros, Lillian; Pais, L.S.; Rodrigues, A.E.; Barreiro, M.F.; Ferreira, Isabel C.F.R.
Fonte: Instituto Politécnico de Bragança Publicador: Instituto Politécnico de Bragança
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
37.46%
Mushrooms are appreciated worldwide, not only for their nutritional value and exquisite flavor and texture, but also for their medicinal properties. There is scientific evidence demonstrating the benefits of mushrooms ingestion due to their richness in bioactive compounds such as mycosterols, in particular ergosterol [1]. Agaricus bisporus L. is the most consumed mushroom worldwide presenting a high content of ergosterol, which represents 90% of its sterol fraction [2]. Thus, it is an interesting matrix to obtain ergosterol, a molecule with a high commercial value. According to literature, ergosterol concentration can vary between 3 and 9 mg per g of dried mushroom. Traditional methods such as maceration and soxhlet extraction are being replaced by emerging methodologies such as ultrasound assisted extraction in order to decrease the used solvent amount, the extraction time and, of course, increasing the extraction yield [3]. In the present work, A. bisporus was extraction solvent type (hexane and ethanol), ultrasound amplitude (50%, 75% and 100%) and sonication time (5 min, 10 min and 15 min). Moreover, in order to decrease the process complexity, it was evaluated the pertinence of the saponification step. Ethanol proved to be the best solvent to extract higher levels of ergosterol (671.5 ± 0.5 mg/100 g dw...

Analysis of the ergosterol biosynthesis pathway cloning, molecular characterization and phylogeny of lanosterol 14α-demethylase (ERG11) gene of Moniliophthora perniciosa

Ceita,Geruza de Oliveira; Vilas-Boas,Laurival Antônio; Castilho,Marcelo Santos; Carazzolle,Marcelo Falsarella; Pirovani,Carlos Priminho; Selbach-Schnadelbach,Alessandra; Gramacho,Karina Peres; Ramos,Pablo Ivan Pereira; Barbosa,Luciana Veiga; Pereira,Gon
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 EN
Relevância na Pesquisa
37.02%
The phytopathogenic fungus Moniliophthora perniciosa (Stahel) Aime & Philips-Mora, causal agent of witches' broom disease of cocoa, causes countless damage to cocoa production in Brazil. Molecular studies have attempted to identify genes that play important roles in fungal survival and virulence. In this study, sequences deposited in the M. perniciosa Genome Sequencing Project database were analyzed to identify potential biological targets. For the first time, the ergosterol biosynthetic pathway in M. perniciosa was studied and the lanosterol 14α-demethylase gene (ERG11) that encodes the main enzyme of this pathway and is a target for fungicides was cloned, characterized molecularly and its phylogeny analyzed. ERG11 genomic DNA and cDNA were characterized and sequence analysis of the ERG11 protein identified highly conserved domains typical of this enzyme, such as SRS1, SRS4, EXXR and the heme-binding region (HBR). Comparison of the protein sequences and phylogenetic analysis revealed that the M. perniciosa enzyme was most closely related to that of Coprinopsis cinerea.