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1.
Food Microbiol ; 123: 104571, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39038885

RESUMO

The pieddecuve (PdC) technique involves using a portion of grape must to undergo spontaneous fermentation, which is then used to inoculate a larger volume of must. This allows for promoting autochthonous yeasts present in the must, which can respect the typicality of the resulting wine. However, the real impact of this practice on the yeast population has not been properly evaluated. In this study, we examined the effects of sulphur dioxide (SO2), temperature, ethanol supplementation, and time on the dynamics and selection of yeasts during spontaneous fermentation to be used as PdC. The experimentation was conducted in a synthetic medium and sterile must using a multi-species yeast consortium and in un-inoculated natural grape must. Saccharomyces cerevisiae dominated both the PdC and fermentations inoculated with commercial wine yeast, displaying similar population growth regardless of the tested conditions. However, using 40 mg/L of SO2 and 1% (v/v) ethanol during spontaneous fermentation of Muscat of Alexandria must allowed the non-Saccharomyces to be dominant during the first stages, regardless of the temperature tested. These findings suggest that it is possible to apply the studied parameters to modulate the yeast population during spontaneous fermentation while confirming the effectiveness of the PdC methodology in controlling alcoholic fermentation.


Assuntos
Etanol , Fermentação , Saccharomyces cerevisiae , Dióxido de Enxofre , Vitis , Vinho , Leveduras , Vitis/microbiologia , Vinho/microbiologia , Vinho/análise , Etanol/metabolismo , Dióxido de Enxofre/farmacologia , Dióxido de Enxofre/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Leveduras/metabolismo , Temperatura , Estresse Fisiológico
2.
Microb Ecol ; 63(4): 844-55, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22167078

RESUMO

The Acidobacteria show a widespread distribution in natural ecosystems. In this study, we analyzed the presence of Acidobacteria in freshwater ponds at Doñana National Park (southwestern Spain). Nucleic acid sequence analysis, quantitative, real-time RT-PCR, and fluorescence in situ hybridization (FISH) were carried out. Acidobacteria in these aquatic environments were investigated using their 16S and 23S rDNA sequences and acidobacterial specific primer pairs through phylogenetic approaches. The presence of up to five subdivisions of Acidobacteria was detected during this study. The analyzed ponds exhibited distinctive patterns of acidobacterial clades. In order to detect their role in ecosystem functions, metabolically active Acidobacteria were detected based upon rRNA analyses. Quantitative, real-time RT-PCR showed a low percentage of metabolically active Acidobacteria at suboxic zones within the water column covered by surface Fe-rich films. Oxygen-saturated areas showed around 4% of total bacterial RNA belonging to Acidobacteria both in the water column and the sediment surface. The morphology of the most abundant Acidobacteria was revealed by FISH as cocci generally in pairs or chains. Enrichment cultures were also obtained and indicated a putative metabolism based on aerobic and heterotrophic characteristics likely taking advantage of the abundant organic matter present at the investigated sites. These results represent a significant contribution toward understanding the distribution and ecological role of the phylum Acidobacteria in natural ecosystems, specifically at Doñana National Park freshwater ponds.


Assuntos
Acidobacteria/genética , Lagoas/microbiologia , Acidobacteria/classificação , Acidobacteria/crescimento & desenvolvimento , Acidobacteria/isolamento & purificação , Primers do DNA , Ecossistema , Hibridização in Situ Fluorescente , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Espanha
3.
Int J Food Microbiol ; 367: 109592, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-35240437

RESUMO

A complex consortium of yeasts is the principal responsible of wine fermentation, being Saccharomyces cerevisiae the main driver. The use of selected yeast, beginning with Saccharomyces strains, is one of the main achievements in microbiological control in the wine industry. However, the use of single strain starters of S. cerevisiae and the limited variability of strains has increased the objections to its use due to the production of wines with a homogeneous profile. New tendencies in winemaking have emphasized the microbiological terroir and challenged the use of selected starters from different areas, including Non-Saccharomyces yeast or multi-strain starters in order to add complexity to the biochemical composition of wines. Nevertheless, these strategies also harbor their own challenges. In the present mini-review, we focus on the alternatives to current commercial yeast starters mainly based on the local multispecies starters or controlled spontaneous fermentations, considering the advantages and limitations of each strategy. Also, we present an ancestral technique based on the use of pre-fermented must (Pied-de-Cuve) because it provides certain microbial control to the alcoholic fermentation while allows the development of autochthonous microorganisms that might confer microbial typicity to the produced wines. Nevertheless, the latest strategy needs further research to establish a scientific background for the selection of the best Pied-de-Cuve development. Finally, the tendencies in winemaking should find a commitment between microbial control to guarantee alcoholic fermentation fulfillment and the production of wines reflecting microbial typicity to respond to consumer demands, without forgetting the scaling up in the cellars.


Assuntos
Saccharomyces , Vitis , Vinho , Fermentação , Saccharomyces cerevisiae , Vitis/microbiologia , Vinho/microbiologia
4.
Res Microbiol ; 160(1): 41-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18984039

RESUMO

Caves with paleolithic paintings are influenced by bacterial development. Altamira Cave (Spain) contains some of the most famous paintings from the Paleolithic era. An assessment of the composition of bacterial communities that have colonized this cave represents a first step in understanding and potentially controlling their proliferation. In this study, areas showing colonization with uncolored microorganisms, referred to as "white colonizations", were analyzed. Microorganisms present in these colonizations were studied using DNA analysis, and those showing significant metabolic activity were detected in RNA-based RNA analysis. Bacterial community fingerprints were obtained both from DNA and RNA analyses, indicating differences between the microorganisms present and metabolically active in these white colonizations. Metabolically active microorganisms represented only a fraction of the total bacterial community present in the colonizations. 16S rRNA gene libraries were used to identify the major representative members of the studied communities. Proteobacteria constituted the most frequently found division both among metabolically active microorganisms (from RNA-based analysis) and those present in the community (from DNA analysis). Results suggest the existence of a huge variety of taxa in white colonizations of the Altamira Cave which represent a potential risk for the conservation of the cave and its paintings.


Assuntos
Bactérias/genética , Ecossistema , Microbiologia Ambiental , Arqueologia , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/metabolismo , Espaços Confinados , Impressões Digitais de DNA , DNA Bacteriano/genética , Biblioteca Gênica , Genes de RNAr , Pinturas , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espanha
5.
Sci Total Environ ; 407(3): 1114-22, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19027143

RESUMO

The conservation of paleolithic paintings such as those in Altamira Cave (Spain) is a primary objective. Recent molecular studies have shown the existence of unknown microbial communities in this cave including anaerobic microorganisms on cave walls. Herein, we analyzed an anaerobic microbial group, the sulfate-reducing bacteria (SRB), from Altamira Cave with potential negative effects on painting conservation. In the present work, the communities of bacteria and SRB were studied through PCR-DGGE analysis. Data suggest that SRB communities represent a significant, highly diverse bacterial group in Altamira Cave. These findings represent a first report on this physiological group on caves with paleolithic paintings and their potential biodegradation consequences. Expanding our knowledge on microbial communities in Altamira Cave is a priority to design appropriate conservation strategies.


Assuntos
Bactérias/classificação , Bactérias/genética , Desulfovibrio/genética , Ar/análise , Arte , Bactérias/isolamento & purificação , Primers do DNA , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Desulfovibrio/isolamento & purificação , Desulfovibrio desulfuricans/genética , Desulfovibrio desulfuricans/isolamento & purificação , Desulfovibrio vulgaris/genética , Desulfovibrio vulgaris/isolamento & purificação , Ecossistema , Geografia , Sedimentos Geológicos/microbiologia , Oxigênio/análise , Pinturas , Paleontologia , Filogenia , Espanha
7.
Rev Neurol ; 61(10): 447-53, 2015 Nov 16.
Artigo em Espanhol | MEDLINE | ID: mdl-26553175

RESUMO

INTRODUCTION: To be able to provide patients with a chronic illness personalised care, it is necessary to know how they live with their disorder. Today, there is no validated scale that assesses this aspect. AIM: To present the pilot study of the preliminary version of the living with a chronic process scale (EC-PC, from the name in Spanish) carried out in patients with Parkinson's disease (PD) in Spain. PATIENTS AND METHODS: A preliminary version of the scale was produced from a literature review and the participation of experts in chronic processes and in PD. Fifteen patients, in all the different stages of PD, answered the preliminary version of the EC-PC (39 items) and a questionnaire about the EC-PC. The viability/acceptability and preliminary aspects of internal consistency were analysed. RESULTS: No domain showed any floor or ceiling effects, but 43.6% of the items had a ceiling effect. The corrected item-total correlation was satisfactory, except in five items. The internal consistency of the five domains was satisfactory, with alpha indexes of 0.81-0.92 and item homogeneity coefficients of 0.19-0.43. The patients identified three items as ambiguous and difficult to answer. Based on these results, 12 items were eliminated and the final version of the EC-PC was drafted, its content being considered satisfactory following its evaluation by expert professionals. CONCLUSIONS: The EC-PC, pending validation, is a viable scale of potential interest in the clinical and community healthcare setting for assessing the ability to live with a chronic process like PD.


TITLE: Estudio piloto sobre la escala de convivencia con un proceso cronico en pacientes con enfermedad de Parkinson.Introduccion. Para proporcionar un cuidado individualizado e integral a los pacientes con una enfermedad cronica es necesario conocer como conviven con su trastorno. En la actualidad, no existe una escala validada que evalue este aspecto. Objetivo. Presentar el estudio piloto de la version preliminar de la escala de convivencia con un proceso cronico (EC-PC) realizado en pacientes con enfermedad de Parkinson (EP) en España. Pacientes y metodos. Se elaboro una version preliminar de la escala a partir de una revision bibliografica y la participacion de expertos en procesos cronicos y en EP. Quince pacientes, en todos los estadios de la EP, cumplimentaron la version preliminar de la EC-PC (39 items) y un cuestionario sobre la EC-PC. Se analizaron la viabilidad/aceptabilidad y aspectos preliminares de consistencia interna. Resultados. Ningun dominio presento efecto suelo o techo, pero un 43,6% de los items tenia efecto techo. La correlacion item-total corregida fue satisfactoria, excepto en cinco items. La consistencia interna de los cinco dominios resulto satisfactoria, con indices alfa de 0,81-0,92 y coeficientes de homogeneidad de los items de 0,19-0,43. Los pacientes identificaron tres items como ambiguos y dificiles de responder. A partir de estos resultados, se eliminaron 12 items y se elaboro la version final de la EC-PC, cuyo contenido fue considerado satisfactorio tras su evaluacion por profesionales expertos. Conclusiones. La EC-PC, pendiente de validacion, es una escala viable, de interes potencial en el ambito clinico y sociosanitario para evaluar la convivencia con un proceso cronico como la EP.


Assuntos
Atividades Cotidianas , Doença de Parkinson/psicologia , Inquéritos e Questionários , Idoso , Idoso de 80 Anos ou mais , Comportamento , Estudos Transversais , Ajustamento Emocional , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Projetos Piloto , Qualidade de Vida , Reprodutibilidade dos Testes , Autocuidado
8.
Naturwissenschaften ; 95(4): 307-15, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18071667

RESUMO

Volcanic eruptions originated the Canary Islands (Spain), and today, different landscapes clearly show that active volcanism. The microbial communities present in these volcanic environments, both at high (above 70 degrees C) and moderate (25-35 degrees C) temperatures, were analyzed. Rock samples were processed using molecular techniques based on both DNA and RNA and complemented with the culture of microorganisms at a wide range of temperatures. Microorganisms detected through RNA-based molecular surveys were mostly related to mesophilic microorganisms, while representatives of hyperthermophiles were not detected. RNA decay curves at 80 degrees C resulted in half-life estimates of less than 2 min for mesophilic microorganisms, supporting a recent and continuous arrival of microorganisms to the high temperature sampled sites. This study constitutes a unique experimental approach showing a great natural potential of microorganisms to spread out to different natural environments. The implications are of great interest for the biogeography, dispersal, and potential distribution of microorganisms, and their genetic information, in natural environments.


Assuntos
Actinobacteria/isolamento & purificação , Alphaproteobacteria/isolamento & purificação , Betaproteobacteria/isolamento & purificação , Erupções Vulcânicas , Actinobacteria/genética , Alphaproteobacteria/genética , Ilhas Atlânticas , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Betaproteobacteria/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Ecossistema , Meio Ambiente , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Reação em Cadeia da Polimerase , RNA Bacteriano/genética , RNA Bacteriano/isolamento & purificação , Espanha
9.
Naturwissenschaften ; 93(1): 42-5, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16292522

RESUMO

Altamira Cave contains valuable paleolithic paintings dating back to 15,000 years. The conservation of these unique paintings is attracting increasing interest, and so, understanding microbial proliferation in Altamira Cave represents a prioritary objective. Here, we show for the first time that members of the Crenarchaeota were metabolically active components of developing microbial communities. RNA was extracted directly from the studied environment, and a number of 16S rRNA gene sequences belonging to the low-temperature Crenarchaeota were detected. Although low-temperature Crenarchaeota detected in a variety of ecosystems by using molecular techniques remain uncultured, this RNA-based study confirms an active participation of the Crenarchaeota in cave biogeochemical cycles.


Assuntos
Crenarchaeota/crescimento & desenvolvimento , Sequência de Bases , Crenarchaeota/classificação , Crenarchaeota/genética , Primers do DNA , Paleontologia , Filogenia , RNA Arqueal/genética , RNA Arqueal/isolamento & purificação , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação , Espanha
10.
Environ Microbiol ; 7(7): 1024-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15946299

RESUMO

Microbial assessment of natural biodiversity is usually achieved through polymerase chain reaction (PCR) amplification. Deoxyribonucleic acid (DNA) sequences from natural samples are often difficult to amplify because of the presence of PCR inhibitors or to the low number of copies of specific sequences. In this study, we propose a non-specific preamplification procedure to overcome the presence of inhibitors and to increase the number of copies prior to carrying out standard amplification by PCR. The pre-PCR step is carried out through a multiple displacement amplification (MDA) technique using random hexamers as priming oligonucleotides and phi 29 DNA polymerase in an isothermal, whole-genome amplification reaction. Polymerase chain reaction amplification using specific priming oligonucleotides allows the selection of the sequences of interest after a preamplification reaction from complex environmental samples. The procedure (MDA-PCR) has been tested on a natural microbial community from a hypogean environment and laboratory assemblages of known bacterial species, in both cases targeting the small subunit ribosomal RNA gene sequences. Results from the natural community showed successful amplifications using the two steps protocol proposed in this study while standard, direct PCR amplification resulted in no amplification product. Amplifications from a laboratory assemblage by the two-step proposed protocol were successful at bacterial concentrations >or= 10-fold lower than standard PCR. Amplifications carried out in the presence of different concentrations of fulvic acids (a soil humic fraction) by the MDA-PCR protocol generated PCR products at concentrations of fulvic acids over 10-fold higher than standard PCR amplifications. The proposed procedure (MDA-PCR) opens the possibility of detecting sequences represented at very low copy numbers, to work with minute samples, as well as to reduce the negative effects on PCR amplifications of some inhibitory substances commonly found in environmental samples.


Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase/métodos , Microbiologia do Solo , Fagos Bacilares , Bactérias/genética , Bactérias/crescimento & desenvolvimento , DNA Bacteriano/análise , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/análise , DNA Polimerase Dirigida por DNA/metabolismo , Ecossistema , Laboratórios , RNA Ribossômico 16S/genética
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