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Colen, Gecernir
Rosa, Carlos Augusto
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Id: biblio-974299
Autor: Penido, Fernanda Corrêa Leal; Piló, Fernanda Barbosa; Sandes, Sávio Henrique de Cicco; Nunes, Álvaro Cantini; Colen, Gecernir; Oliveira, Evelyn de Souza; Rosa, Carlos Augusto; Lacerda, Inayara Cristina Alves.
Título: Selection of starter cultures for the production of sour cassava starch in a pilot-scale fermentation process
Fonte: Braz. j. microbiol;49(4):823-831, Oct.-Dec. 2018. tab, graf.
Idioma: en.
Resumo: ABSTRACT Sour cassava starch (Polvilho azedo) is obtained from a spontaneous fermentation conducted by microorganisms from raw materials and fermentation tanks. This product is traditionally used in the baking industry for the manufacture of biscuits and Brazilian cheese breads. However, the end of fermentation is evaluated empirically, and the process occurs without standardization, which results in products of inconsistent quality. Predominant microbiota from a cassava flour manufacturer was isolated in order to select starter cultures for the production of sour cassava starch in a pilot-scale fermentation process. Lactic acid bacteria and yeasts were isolated, enumerated and grouped by Restriction Fragment Length Polymorphism, and PCR fingerprinting, respectively. One isolate of each molecular profile was identified by sequencing of the rRNA gene. LAB were prevalent throughout the entire process. Lactobacillus brevis (21.5%), which produced the highest values of acidity, and Lactobacillus plantarum (13.9%) were among the most frequent species. Pichia scutulata (52.2%) was the prevalent yeast and showed amylolytic activity. The aforementioned species were tested as single and mixed starter cultures in a pilot-scale fermentation process for 28 days. L. plantarum exhibited better performance as a starter culture, which suggests its potential for the production of sour cassava starch.
Descritores: Amido/metabolismo
Leveduras/metabolismo
Manihot/química
Lactobacillus/metabolismo
-Amido/química
Leveduras/genética
Brasil
Manihot/metabolismo
Fermentação
Microbiota
Microbiologia de Alimentos
Lactobacillus/isolamento & purificação
Lactobacillus/genética
Responsável: BR1.1 - BIREME


  2 / 454 LILACS  
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Rosa, Carlos Augusto
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Id: biblio-974288
Autor: Piló, Fernanda Barbosa; Carvajal-Barriga, Enrique Javier; Guamán-Burneo, Maria Cristina; Portero-Barahona, Patricia; Dias, Arthur Matoso Morato; Freitas, Larissa Falabella Daher de; Gomes, Fátima de Cássia Oliveira; Rosa, Carlos Augusto.
Título: Saccharomyces cerevisiae populations and other yeasts associated with indigenous beers (chicha) of Ecuador
Fonte: Braz. j. microbiol;49(4):808-815, Oct.-Dec. 2018. tab, graf.
Idioma: en.
Resumo: ABSTRACT Chicha, a type of beer made mainly with maize or cassava, is a traditional fermented beverage of the Andean region. There have only been a few studies on yeasts associated with chicha fermentation, and the species diversity occurring during the production of this beverage is not known. The objective of this study was to determine the biodiversity of yeasts in chicha, and to characterize the Saccharomyces cerevisiae populations associated with the production of chicha de jora, seven-grain chicha, chicha de yuca, and chicha de morocho in Ecuador. The molecular diversity of S. cerevisiae populations was determined by restriction polymorphism mitochondrial profiles. The beverages were characterized based on their physicochemical parameters. Twenty-six species were identified, and the most prevalent species were S. cerevisiae and Torulaspora delbrueckii. Other yeast species were isolated at low frequencies. Among 121 isolates of S. cerevisiae, 68 different mtDNA molecular profiles were identified. These results showed that chichas are fermented by a high number of different strains of S. cerevisiae. Some other species provided a minor contribution to the fermentation process. The chicha presented generally similar physicochemical parameters to those observed for other traditional fermented beverages, and can be considered as an acid fermented beverage.
Descritores: Saccharomyces cerevisiae/isolamento & purificação
Cerveja/microbiologia
Leveduras/isolamento & purificação
Leveduras/metabolismo
-Saccharomyces cerevisiae/classificação
Saccharomyces cerevisiae/genética
Saccharomyces cerevisiae/metabolismo
Cerveja/análise
Leveduras/classificação
Leveduras/genética
Manihot/metabolismo
Manihot/microbiologia
Zea mays/metabolismo
Zea mays/microbiologia
Biodiversidade
Equador
Fermentação
Responsável: BR1.1 - BIREME


  3 / 454 LILACS  
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Texto completo
Id: biblio-839329
Autor: Lopes, Mario Lucio; Paulillo, Silene Cristina de Lima; Godoy, Alexandre; Cherubin, Rudimar Antonio; Lorenzi, Marcel Salmeron; Giometti, Fernando Henrique Carvalho; Bernardino, Claudemir Domingos; Amorim Neto, Henrique Berbert de; Amorim, Henrique Vianna de.
Título: Ethanol production in Brazil: a bridge between science and industry
Fonte: Braz. j. microbiol;47(supl.1):64-76, Oct.-Dec. 2016. tab, graf.
Idioma: en.
Resumo: ABSTRACT In the last 40 years, several scientific and technological advances in microbiology of the fermentation have greatly contributed to evolution of the ethanol industry in Brazil. These contributions have increased our view and comprehension about fermentations in the first and, more recently, second-generation ethanol. Nowadays, new technologies are available to produce ethanol from sugarcane, corn and other feedstocks, reducing the off-season period. Better control of fermentation conditions can reduce the stress conditions for yeast cells and contamination by bacteria and wild yeasts. There are great research opportunities in production processes of the first-generation ethanol regarding high-value added products, cost reduction and selection of new industrial yeast strains that are more robust and customized for each distillery. New technologies have also focused on the reduction of vinasse volumes by increasing the ethanol concentrations in wine during fermentation. Moreover, conversion of sugarcane biomass into fermentable sugars for second-generation ethanol production is a promising alternative to meet future demands of biofuel production in the country. However, building a bridge between science and industry requires investments in research, development and transfer of new technologies to the industry as well as specialized personnel to deal with new technological challenges.
Descritores: Etanol
Fermentação
-Ciência
Tecnologia
Leveduras/metabolismo
Microbiologia Industrial
Brasil
Biocombustíveis
Limites: Seres Humanos
Responsável: BR1.1 - BIREME


  4 / 454 LILACS  
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Id: biblio-828185
Autor: Castillo-Castillo, Y; Ruiz-Barrera, O; Burrola-Barraza, M. E; Marrero-Rodriguez, Y; Salinas-Chavira, J; Angulo-Montoya, C; Corral-Luna, A; Arzola-Alvarez, C; Itza-Ortiz, M; Camarillo, J.
Título: Isolation and characterization of yeasts from fermented apple bagasse as additives for ruminant feeding
Fonte: Braz. j. microbiol;47(4):889-895, Oct.-Dec. 2016. tab, graf.
Idioma: en.
Resumo: Abstract Solid-state fermentation can be used to produce feeds for ruminants, which can provide an enriched population of yeasts to improve ruminal fermentation. Fermentation of apple bagasse was performed to obtain a yeast-rich product, with the objective of isolating, identifying, and characterizing yeast strains and testing their capability to enhance in vitro ruminal fermentation of fibrous feeds. Yeasts were isolated from apple bagasse fermented under in vitro conditions, using rumen liquor obtained from cannulated cows and alfalfa as a fibrous substrate. A total of 16 new yeast strains were isolated and identified by biochemical and molecular methods. The strains were designated Levazot, followed by the isolate number. Their fermentative capacity was assessed using an in vitro gas production method. Strain Levazot 15 (Candida norvegensis) showed the greatest increase in gas production (p < 0.05) compared with the yeast-free control and positively affected in vitro ruminal fermentation parameters of alfalfa and oat straw. Based on these results, it was concluded that the Levazot 15 yeast strain could be potentially used as an additive for ruminants consuming high-fiber diets. However, further studies of effects of these additives on rumen digestion, metabolism, and productive performance of ruminants are required.
Descritores: Leveduras/isolamento & purificação
Leveduras/classificação
Celulose
Malus
Aditivos Alimentares
Ração Animal/microbiologia
-Filogenia
Leveduras/genética
Leveduras/metabolismo
Ruminantes
Fermentação
Limites: Animais
Responsável: BR1.1 - BIREME


  5 / 454 LILACS  
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Weiblen, Rudi
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Id: biblio-828184
Autor: Arenhart, Sandra; Silva Junior, José Valter Joaquim; Flores, Eduardo Furtado; Weiblen, Rudi; Gil, Laura Helena Vega Gonzales.
Título: Use of homologous recombination in yeast to create chimeric bovine viral diarrhea virus cDNA clones
Fonte: Braz. j. microbiol;47(4):993-999, Oct.-Dec. 2016. tab, graf.
Idioma: en.
Resumo: Abstract The open reading frame of a Brazilian bovine viral diarrhea virus (BVDV) strain, IBSP4ncp, was recombined with the untranslated regions of the reference NADL strain by homologous recombination in Saccharomyces cerevisiae, resulting in chimeric full-length cDNA clones of BVDV (chi-NADL/IBSP4ncp#2 and chi-NADL/IBSP4ncp#3). The recombinant clones were successfully recovered, resulting in viable viruses, having the kinetics of replication, focus size, and morphology similar to those of the parental virus, IBSP4ncp. In addition, the chimeric viruses remained stable for at least 10 passages in cell culture, maintaining their replication efficiency unaltered. Nucleotide sequencing revealed a few point mutations; nevertheless, the phenotype of the rescued viruses was nearly identical to that of the parental virus in all experiments. Thus, genetic stability of the chimeric clones and their phenotypic similarity to the parental virus confirm the ability of the yeast-based homologous recombination to maintain characteristics of the parental virus from which the recombinant viruses were derived. The data also support possible use of the yeast system for the manipulation of the BVDV genome.
Descritores: Leveduras/genética
Genoma Viral
DNA Complementar
Vírus da Diarreia Viral Bovina/genética
Recombinação Homóloga
-Replicação Viral
Leveduras/metabolismo
Linhagem Celular
Fases de Leitura Aberta
Análise de Sequência de DNA
Vírus da Diarreia Viral Bovina/fisiologia
Vírus da Diarreia Viral Bovina/ultraestrutura
Limites: Animais
Bovinos
Responsável: BR1.1 - BIREME


  6 / 454 LILACS  
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Texto completo
Id: biblio-975604
Autor: Ali, Khaled; Hamed, Mahmood A; Hassan, Hameda; Esmail, Amira; Sheneef, Abeer.
Título: Identification of Fungal Pathogens in Otomycosis and Their Drug Sensitivity: Our Experience
Fonte: Int. arch. otorhinolaryngol. (Impr.);22(4):400-403, Oct.-Dec. 2018. tab.
Idioma: en.
Resumo: Abstract Introduction Otomycosis is a common problem in otolaryngology practice. However, we usually encounter some difficulties in its treatment because many patients show resistance to antifungal agents, and present high recurrence rate. Objectives To determine the fungal pathogens that cause otomycosis as well as their susceptibility to the commonly used antifungal agents. Additionally, to discover the main reasons for antifungal resistance. Methods We conducted an experimental descriptive study on 122 patients clinically diagnosed with otomycosis from April 2016 to April 2017. Aural discharge specimens were collected for direct microscopic examination and fungal culture. In vitro antifungal susceptibility testing was performed against the commonly used antifungal drugs. We tested the isolated fungi for their enzymatic activity. Results Positive fungal infection was found in 102 samples. The most common fungal pathogens were Aspergillus and Candida species, with Aspergillus niger being the predominant isolate (51%). The antifungal susceptibility testing showed that mold isolates had the highest sensitivity to voriconazole (93.48%), while the highest resistance was to fluconazole (100%). For yeast, the highest sensitivity was to nystatin (88.24%), followed by amphotericin B (82.35%), and the highest resistance was to terbinafine (100%), followed by Itraconazole (94.12%). Filamentous fungi expressed a high enzymatic ability, making them more virulent. Conclusion The Aspergillus and Candida species are the most common fungal isolates in otomycosis. Voriconazole and Nystatin are the medications of choice for the treatment of otomycosis in our community. The high virulence of fungal pathogens is owed to their high enzymatic activity. Empirical use of antifungals should be discouraged.
Descritores: Farmacorresistência Fúngica
Otomicose/microbiologia
Fungos/isolamento & purificação
Antifúngicos/farmacologia
-Aspergillus/isolamento & purificação
Aspergillus niger/isolamento & purificação
Leveduras/isolamento & purificação
Candida/isolamento & purificação
Testes de Sensibilidade Microbiana
Anfotericina B/farmacologia
Epidemiologia Descritiva
Epidemiologia Experimental
Itraconazol/farmacologia
Voriconazol/farmacologia
/farmacologia
AMERICAN HEART ASSOCIATION9TEMEFOS/farmacologia
Limites: Seres Humanos
Masculino
Feminino
Lactente
Pré-Escolar
Criança
Adolescente
Adulto
Meia-Idade
Idoso
Responsável: BR66.1 - Divisão de Biblioteca e Documentação


  7 / 454 LILACS  
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Id: biblio-1022493
Autor: Liu, Dongmei; Zhu, Hanyu; Chen, Yue; Zheng, Liesheng; Chen, Liguo; Ma, Aimin.
Título: Cloning and heterologous expression of a hydrophobin gene Ltr. hyd from the tiger milk mushroom Lentinus tuber-regium in yeast-like cells of Tremella fuciformis
Fonte: Electron. j. biotechnol;32:6-12, Mar. 2018. tab, graf, ilus.
Idioma: en.
Projeto: National Natural Science Foundation of China (NSFC).
Resumo: Background: Hydrophobins are small proteins secreted by filamentous fungi, which show a highly surface activity. Because of the signally self-assembling abilities and surface activities, hydrophobins were considered as candidates in many aspects, for example, stabilizing foams and emulsions in food products. Lentinus tuber-regium, known as tiger milk mushroom, is both an edible and medicinal sclerotium-producing mushroom. Up to now, the hydrophobins of L. tuber-regium have not been identified. Results: In this paper, a Class I hydrophobin gene, Ltr.hyd, was cloned from L. tuber-regium and expressed in the yeast-like cells of Tremella fuciformis mediated by Agrobacterium tumefaciens. The expression vector pGEH-GH was under the control of T. fuciformis glyceraldehyde-3-phosphate dehydrogenase gene (gpd) promoter. The integration of Ltr.hyd into the genome of T. fuciformis was confirmed by PCR, Southern blot, fluorescence observation and quantitative real-time PCR (qRT-PCR). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that recombinant hydrophobin rLtr.HYD with an expected molecular mass of 13 kDa was extracted. The yield of rLtr.HYD was 0.66 mg/g dry weight. The emulsifying activity of rLtr.HYD was better than the typical food emulsifiers sodium caseinate and Tween 20. Conclusions: We evaluated the emulsifying property of hydrophobin Ltr.HYD, which can be potentially used as a food emulsifier.
Descritores: Basidiomycota/metabolismo
Proteínas Fúngicas/genética
Lentinula/genética
Lentinula/metabolismo
-Transformação Genética
Basidiomycota/enzimologia
Leveduras
Proteínas Fúngicas/metabolismo
Southern Blotting
Clonagem Molecular
Agrobacterium tumefaciens/metabolismo
Análise de Sequência
Emulsificantes
Eletroforese em Gel de Poliacrilamida
Reação em Cadeia da Polimerase em Tempo Real
Gliceraldeído-3-Fosfato Desidrogenases/metabolismo
Microscopia de Fluorescência
Responsável: CL1.1 - Biblioteca Central


  8 / 454 LILACS  
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Id: biblio-1022044
Autor: Revin, Victor; Atykyan, Nelli; Lyovina, Ekaterina; Dragunova, Yuliya; Ushkina, Victoriya.
Título: Effect of ultraviolet radiation on physiological and biochemical properties of yeast Saccharomyces cerevisiae during fermentation of ultradispersed starch raw material
Fonte: Electron. j. biotechnol;31:61-66, Jan. 2018. graf, ilus, tab.
Idioma: en.
Projeto: Ministry of Education and Science of the Russian Federation.
Resumo: Background: Study of correlation between pretreatment of yeast with ultraviolet radiation and efficiency of further fermentation of wort made of ultrafine grain particles to ethanol. Results: We investigated three races of industrial yeast Saccharomyces cerevisiae (native and irradiated by ultraviolet). Physiological properties during fermentation of starchy wort were tested in all variants. It was shown that activation of the yeast by ultraviolet radiation allows to further increase the ethanol yield by 25% on average compared with the native yeast races when using thin (up to micro- and nano-sized particles) or standard grain grinding. Conclusions: Using mechanical two-stage grinding of starchy raw materials and ultraviolet pretreatment of yeast, the efficiency of saccharification of starch and fermentation of wort to ethanol was increased.
Descritores: Saccharomyces cerevisiae/efeitos da radiação
Raios Ultravioleta
Leveduras/efeitos da radiação
Etanol/efeitos da radiação
-Saccharomyces/metabolismo
Amido
Temperatura Ambiente
Leveduras/metabolismo
Estabilidade Enzimática
Etanol/metabolismo
Fermentação
Glucose
Amilases
Responsável: CL1.1 - Biblioteca Central


  9 / 454 LILACS  
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Id: biblio-1016090
Autor: Castro, Daniela E; Murguía-Romero, Miguel; Thomé, Patricia E; Peña, Antonio; Calderón-Torres, Marissa.
Título: Putative 3-nitrotyrosine detoxifying genes identified in the yeast Debaryomyces hansenii: in silico search of regulatory sequences responsive to salt and nitrogen stress
Fonte: Electron. j. biotechnol;29:1-6, sept. 2017. graf, tab.
Idioma: en.
Projeto: DGAPA-UNAM.
Resumo: Background: During salt stress, the yeast Debaryomyces hansenii synthesizes tyrosine as a strategy to avoid the oxidation of proteins. Tyrosine reacts with nitrogen radicals to form 3-nitrotyrosine. 3-nitrotyrosine prevents the effects of associated oxidative stress and thus contributes to the high halotolerace of the yeast. However, the mechanism of how D. hansenii counteracts the presence of this toxic compound is unclear. In this work, we evaluated D. hansenii's capacity to assimilate 3-nitrotyrosine as a unique nitrogen source and measured its denitrase activity under salt stress. To identify putative genes related to the assimilation of 3-nitrotyrosine, we performed an in silico search in the promoter regions of D. hansenii genome. Results: We identified 15 genes whose promoters had binding site sequences for transcriptional factors of sodium, nitrogen, and oxidative stress with oxidoreductase and monooxygenase GO annotations. Two of these genes, DEHA2E24178g and DEHA2C00286g, coding for putative denitrases and having GATA sequences, were evaluated by RT-PCR and showed high expression under salt and nitrogen stress. Conclusions: D. hansenii can grow in the presence of 3-nitrotyrosine as the only nitrogen source and has a high specific denitrase activity to degrade 3-nitrotyrosine in 1 and 2 M NaCl stress conditions. The results suggest that given the lack of information on transcriptional factors in D. hansenii, the genes identified in our in silico analysis may help explain 3-nitrotyrosine assimilation mechanisms.
Descritores: Tirosina/análogos & derivados
Tirosina/metabolismo
Debaromyces/genética
Debaromyces/metabolismo
-Tirosina/genética
Transcrição Genética
Leveduras
Sequências Reguladoras de Ácido Nucleico
Regiões Promotoras Genéticas
Estresse Oxidativo
Reação em Cadeia da Polimerase em Tempo Real
Osmorregulação
Extremófilos
FRONTAL LOBE0
Nitrogênio/metabolismo
Responsável: CL1.1 - Biblioteca Central


  10 / 454 LILACS  
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Id: biblio-1015723
Autor: Wang, Jiayi; Lu, Lei; Feng, Fujuan.
Título: Combined strategies for improving production of a thermo-alkali stable laccase in Pichia pastoris
Fonte: Electron. j. biotechnol;28:7-13, July. 2017. tab, graf, ilus.
Idioma: en.
Projeto: National Natural Science Foundation of China; . Fundamental Research Funds for the Central Universities.
Resumo: Background: Laccases are copper-containing enzymes which have been used as green biocatalysts for many industrial processes. Although bacterial laccases have high stabilities which facilitate their application under harsh conditions, their activities and production yields are usually very low. In this work, we attempt to use a combinatorial strategy, including site-directed mutagenesis, codon and cultivation optimization, for improving the productivity of a thermo-alkali stable bacterial laccase in Pichia pastoris. Results: A D500G mutant of Bacillus licheniformis LS04 laccase, which was constructed by site-directed mutagenesis, demonstrated 2.1-fold higher activity when expressed in P. pastoris. The D500G variant retained similar catalytic characteristics to the wild-type laccase, and could efficiently decolorize synthetic dyes at alkaline conditions. Various cultivation factors such as medium components, pH and temperature were investigated for their effects on laccase expression. After cultivation optimization, a laccase activity of 347 ± 7 U/L was finally achieved for D500G after 3 d of induction, which was about 9.3 times higher than that of wild-type enzyme. The protein yield under the optimized conditions was about 59 mg/L for D500G. Conclusions: The productivity of the thermo-alkali stable laccase from B. licheniformis expressed in P. pastoris was significantly improved through the combination of site-directed mutagenesis and optimization of the cultivation process. The mutant enzyme retains good stability under high temperature and alkaline conditions, and is a good candidate for industrial application in dye decolorization.
Descritores: Pichia/metabolismo
Lacase/biossíntese
Lacase/genética
Bacillus licheniformis/enzimologia
-Temperatura Ambiente
Leveduras
Estabilidade Enzimática
Catálise
Mutagênese
Lacase/metabolismo
Corantes/metabolismo
Concentração de Íons de Hidrogênio
Responsável: CL1.1 - Biblioteca Central



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