Influence of wine-like conditions on arginine utilization by lactic acid bacteria

Wine can contain trace amounts of ethyl carbamate (EC), a carcinogen formed when ethanol reacts with carbamyl compounds such as citrulline. EC is produced from arginine by lactic acid bacteria (LAB), e.g., Lactobacillus and Pediococcus. Although the amounts of EC in wine are usually negligible, over the last few years there has been a slight butsteady increase, as climate change has increased temperatures and alcohol levels have become proportionately higher, both of which favor EC formation. In this study, resting cells of LAB were used to evaluate the effects of ethanol, glucose, malic acid, and low pH on the ability of non-oenococcal strains of these bacteria to degrade arginine and excrete citrulline. Malic acid was found to clearly inhibit arginine consumption in all strains. The relation between citrulline produced and arginine consumed was clearly higher in the presence of ethanol (10-12 %) and at low pH (3.0), which is consistent with both the decreased amount of ornithine produced from arginine and the reduction in arginine degradation. In L. brevis and L. buchneri strains isolated from wine and beer, respectively, the synthesis of citrulline from arginine was highest

Proyecto Cenit-Demeter: resultados vitícolas

Desarrollar estrategias y métodos vitícolas y enológicos frente al cambio climático. Aplicación de nuevas tecnologías que mejoren la eficiencia de los procesos resultante

Isolation, selection, and characterization of highly ethanol-tolerant strains of Oenococcus oeni from south Catalonia

Twenty-one strains of Oenococcus oeni were isolated during the malolactic fermentation of wines from south Catalonia. Due to their high ethanol tolerance (14 %, or more), these strains may serve as promising starters. The strains were screened by assays in a wine-like medium and by their co-inoculation in wine, resulting in the selection of well-performing strains, subsequently shown not to produce the main biogenic amines and lacking the genes involved in their synthesis. The genetic diversity of the isolates was studied by multilocus sequence typing (MLST), in which seven housekeeping genes were sequenced. Although the concatenated allelic profi le of some strains was the same, the profi les obtained by random amplifi cation of polymorphic DNA together with the variable number of tandem repeats at several loci showed that none of the strains were identical. A phylogenetic tree was constructed based on MLST with the seven genes and clearly showed two phylogroups, in accordance with previous studies. The best-performing strains occurred in members of both subgroups, suggesting that the grouping of housekeeping genes is not directly related to adaptation and ethanol tolerance. [Int Microbiol 2013; 16(2):113-123]Keywords: Oenococcus oeni; malolactic fermentation; wine production; multilocus sequence typing (MLST);strain selectio

Selection and characterization of autochthonous strains of Oenococcus oeni for vinification in Priorat (Catalonia, Spain)

The use of autochthonous strains of Oenococcus oeni for inducing malolactic fermentation (MLF) in wines is increasing because they are well adapted to the conditions of a specific area. The main aim of this work was to select O. oeni strains from Priorat (Catalonia, Spain) wines that would be able to carry out the MLF while maintaining the characteristics of the wine. Forty-five autochthonous strains were selected based on their degradation of L-malic acid, resistance to low pH and high ethanol, and the absence of biogenic amine genes. The three strains with the best characteristics were inoculated and MLF was carried out successfully with the final wines showing good characteristics. One of the inoculated O. oeni strains would be a good candidate to study as possible starter culture. It shows that autochthonous O. oeni strains, once selected, have the potential to be used as an inoculum for wines.Multi-strain indigenous Yeast and Bacterial starters for ‘Wild-ferment’ Wine productio

Els bacteris de la fermentació malolàctica del vi

Sense resu

Poetry, music and school: a triangle of sound

L’article parteix de tres idees fonamentals: a) la importància de l’oralitat, en l’educació general i en l’educació poètica i artística en concret; b) la necessitat d’educar de forma holística, més enllà de cada disciplina; i c) els forts lligams històrics entre cançó i poesia en l’àmbit de la didàctica. A partir d’aquí, s’aborda la relació entre poesia i música des de quatre dimensions (fenomenològica, comparativa, complementària i integradora) i se n’extreuen implicacions educatives i didàctiques. Des d’aquest plantejament i de cara a facilitar un ús integrat d’ambdues disciplines, l’article planteja un marc comú entre poesia dita en veu alta i música que en faciliti l’anàlisi. Es proposa un esquema amb tres dimensions (recepció sonora, interpretació escènica i creació) que permeti la comprensió de les obres i l’adquisició del sentit crític. Finalment, com a exemple il·lustratiu, es mostra l’aplicació de l’esquema a un poema recitat per Enric Casasses ____________________________________________________ L'article part de trois idées fondamentales: a) l'importance de l'oralité dans l'enseignement en général, et tout particulièrement dans celui de la poésie et de l'art ; b) la nécessité d'enseigner holistiquement, par delà chacune des disciplines ; et c) les liens historiques étroits entre la chanson et la poésie dans le domaine didactique. Nous analysons ensuite quatre dimensions de la relation entre la poésie et la musique (phénoménologique, comparative, complémentaire et d'intégration), afin d'en extraire des conséquences dans la pratique de l'enseignement et de la didactique. Dans cette perspective, et afin de faciliter un usage adapté aux deux disciplines, l'article propose d'établir un cadre unique à la poésie récitée à voix haute et à la musique, pour une analyse plus aisée. Nous proposons un schéma à trois dimensions (réception sonore, interprétation scénique et création) permettant de comprendre les œuvres et d'acquérir un esprit critique. Enfin, pour illustrer notre propos, nous reportons notre schéma à un poème récité par Enric CasassesEl artículo parte de tres ideas fundamentales: a) la importancia de la oralidad, en la educación en general y en la educación poética y artística en particular; b) la necesidad de educar de forma holística, más allá de cada disciplina; y c) los fuertes lazos históricos entre canción y poesía en el ámbito de la didáctica. A partir de este punto, se aborda la relación entre poesía y música desde cuatro dimensiones (fenomenológica, comparativa, complementaria e integradora) extrayendo de cada una implicaciones educativas y didácticas. Desde este planteamiento y con el objetivo de facilitar un uso integrado de ambas disciplinas, el artículo presenta un marco común entre poesía dicha en voz alta y música que facilite su análisis. Se propone un esquema con tres dimensiones (recepción sonora, interpretación escénica y creación) que permita la comprensión de las obras y la adquisición del sentido crítico. Finalmente, como ejemplo ilustrativo, se muestra la aplicación del esquema un poema recitado por Enric CasassesThree fundamental ideas are the starting point of this article: a) the importance in education, especially poetic and artistic education, of oral tradition; b) the need of educating in a holistic way, beyond each specific subject; and c) the strong historical ties between singing and poetry within the field of teaching. From here, the connection between poetry and music is approached from four dimensions (phenomenological, comparative, complementary and integrative), and educational and didactic implications are drawn. Based on this approach, and as a way to facilitate the integrated use of the two disciplines, for poetry read aloud and music, the article puts forward a common frame that will ease further analysis. A diagram with three dimensions (sound recep-tion, stage performance and production) that allows the understanding of the works and the acquisition of critical thinking is proposed. Finally, the application of the diagram to a poem recited by Enric Casasses is shown as an illustrative exampl

Poesia, música i escola : un triangle sonor

L'article parteix de tres idees fonamentals: a) la importància de l'oralitat, en l'educació general i en l'educació poètica i artística en concret; b) la necessitat d'educar de forma holística, més enllà de cada disciplina; i c) els forts lligams històrics entre cançó i poesia en l'àmbit de la didàctica. A partir d'aquí, s'aborda la relació entre poesia i música des de quatre dimensions (fenomenològica, comparativa, complementària i integradora) i se n'extreuen implicacions educatives i didàctiques. Des d'aquest plantejament i de cara a facilitar un ús integrat d'ambdues disciplines, l'article planteja un marc comú entre poesia dita en veu alta i música que en faciliti l'anàlisi. Es proposa un esquema amb tres dimensions (recepció sonora, interpretació escènica i creació) que permeti la comprensió de les obres i l'adquisició del sentit crític. Finalment, com a exemple il·lustratiu, es mostra l'aplicació de l'esquema a un poema recitat per Enric Casasses.El artículo parte de tres ideas fundamentales: a) la importancia de la oralidad, en la educación en general y en la educación poética y artística en particular; b) la necesidad de educar de forma holística, más allá de cada disciplina; y c) los fuertes lazos históricos entre canción y poesía en el ámbito de la didáctica. A partir de este punto, se aborda la relación entre poesía y música desde cuatro dimensiones (fenomenológica, comparativa, complementaria e integradora) extrayendo de cada una de las implicaciones educativas y didácticas. Desde este planteamiento y con el objetivo de facilitar un uso integrado de ambas disciplinas, el artículo presenta un marco común entre poesía dicha en voz alta y música que facilite su análisis. Se propone un esquema con tres dimensiones (recepción sonora, interpretación escénica y creación) que permita la comprensión de las obras y la adquisición del sentido crítico. Finalmente, como ejemplo ilustrativo, se muestra la aplicación del esquema a un poema recitado por Enric Casasses.L'article part de trois idées fondamentales: a) l'importance de l'oralité dans l'enseignement en général, et tout particulièrement dans celui de la poésie et de l'art ; b) la nécessité d'enseigner holistiquement, par delà chacune des disciplines ; et c) les liens historiques étroits entre la chanson et la poésie dans le domaine didactique. Nous analysons ensuite quatre dimensions de la relation entre la poésie et la musique (phénoménologique, comparative, complémentaire et d'intégration), afin d'en extraire des conséquences dans la pratique de l'enseignement et de la didactique. Dans cette perspective, et afin de faciliter un usage adapté aux deux disciplines, l'article propose d'établir un cadre unique à la poésie récitée à voix haute et à la musique, pour une analyse plus aisée. Nous proposons un schéma à trois dimensions (réception sonore, interprétation scénique et création) permettant de comprendre les œuvres et d'acquérir un esprit critique. Enfin, pour illustrer notre propos, nous reportons notre schéma à un poème récité par Enric Casasses.Three fundamental ideas are the starting point of this article: a) the importance in education, especially poetic and artistic education, of oral tradition; b) the need of educating in a holistic way, beyond each specific subject; and c) the strong historical ties between singing and poetry within the field of teaching. From here, the connection between poetry and music is approached from four dimensions (phenomenological, comparative, complementary and integrative), and educational and didactic implications are drawn. Based on this approach, and as a way to facilitate the integrated use of the two disciplines, for poetry read aloud and music, the article puts forward a common frame that will ease further analysis. A diagram with three dimensions (sound reception, stage performance and production) that allows the understanding of the works and the acquisition of critical thinking is proposed. Finally, the application of the diagram to a poem recited by Enric Casasses is shown as an illustrative example

Transcriptomic and proteomic analysis of Oenococcus oeni adaptation to wine stress conditions

Oenococcus oeni, the main lactic acid bacteria responsible for malolactic fermentation in wine, has to adapt to stressful conditions, such as low pH and high ethanol content. In this study, the changes in the transcriptome and the proteome of O. oeni PSU-1 during the adaptation period before MLF start have been studied. DNA microarrays were used for the transcriptomic analysis and two complementary proteomic techniques, 2-D DIGE and iTRAQ labeling were used to analyze the proteomic response. One of the most influenced functions in PSU-1 due to inoculation into wine-like medium (WLM) was translation, showing the over-expression of certain ribosomal genes and the corresponding proteins. Amino acid metabolism and transport was also altered and several peptidases were up regulated both at gene and protein level. Certain proteins involved in glutamine and glutamate metabolism showed an increased abundance revealing the key role of nitrogen uptake under stressful conditions. A strong transcriptional inhibition of carbohydrate metabolism related genes was observed. On the other hand, the transcriptional up-regulation of malate transport and citrate consumption was indicative of the use of L-malate and citrate associated to stress response and as an alternative energy source to sugar metabolism. Regarding the stress mechanisms, our results support the relevance of the thioredoxin and glutathione systems in the adaptation of O. oeni to wine related stress. Genes and proteins related to cell wall showed also significant changes indicating the relevance of the cell envelop as protective barrier to environmental stress. The differences found between transcriptomic and proteomic data suggested the relevance of post-transcriptional mechanisms and the complexity of the stress response in O. oeni adaptation. Further research should deepen into the metabolisms mostly altered due to wine conditions to elucidate the role of each mechanism in the O. oeni ability to develop MLF.This work was supported by grants AGL2009-07369ALI and AGL2012-34866ALI from the Spanish Ministry of Economy and Competitiveness. MM is grateful to the pre-doctoral fellowship from the Universitat Rovira i Virgili. JB wish to thank to the Spanish Government for his “Ayuda para la Formación Posdoctoral” research contract.Peer Reviewe