85 research outputs found
The role of nitrogen uptake on the competition ability of three vineyard Saccharomyces cerevisiae strains
Three vineyard strains of Saccharomyces cerevisiae, P301.4, P304.4 and P254.12, were assayed in comparison with a commercial industrial strain, QA23. The aim was to understand if nitrogen availability could influence strain competition ability during must fermentation. Pairwise-strain fermentations and co-fermentations with the simultaneous presence of the four strains were performed in synthetic musts at two nitrogen levels: control nitrogen condition (CNC) that assured the suitable assimilable nitrogen amount required by the yeast strains to complete the fermentation and low nitrogen condition (LNC) where nitrogen is present at very low level.
Results suggested a strong involvement of nitrogen availability, as the frequency in must of the vineyard strains, respect to QA23, in LNC was always higher than that found in CNC. Moreover, in CNC only strain P304.4 reached the same strain frequency as QA23. P304.4 competition ability increased during the fermentation, indicating better performance when nitrogen availability was dropping down. P301.4 was the only strain sensitive to QA23 killer toxin. In CNC, when it was co-inoculated with the industrial strain QA23, P301.4 was never detected. In LNC, P301.4 after 12 h accounted for 10% of the total population. This percentage increased after 48 h (20%).
Single-strain fermentations were also run in both conditions and the nitrogen metabolism further analyzed. Fermentation kinetics, ammonium and amino-acid consumptions and the expression of genes under nitrogen catabolite repression evidenced that vineyard yeasts, and particularly strain P304.4, had higher nitrogen assimilation rate than the commercial control. In conclusion, the high nitrogen assimilation rate seems to be an additional strategy that allowed vineyard yeasts successful competition during the growth in grape musts
Perspectives of Latino Parents of School-aged Children in Northern Nevada Regarding Beverage Choices and Nutrition Education
This project aimed to explore the role of sugary drinks within the family setting of the Latino community in Northern Nevada. The resulting information will be used to strengthen the on-going Rethink Your Drink campaign. Latino children have a higher rate of sugary drink consumption compared to other race and ethnic groups. In order to reduce sugary drink intake effectively among members of Latino households, nutrition education efforts must be culturally relevant. Thirteen interviews with Latino parents in the Northern Nevada were conducted for the purpose of discovering significant considerations surrounding the beverage choices for their children; and their interests and preferences regarding nutrition information. The resulting qualitative data included the following considerations that Latino parents make when buying drinks for their children: cost, taste, convenience, nutrition, and their child(ren)âs preference. Topics of interest among the Latino parents regarding nutrition information include food for meals, food specifically for snack time, drinks, grocery shopping (including recipes and meal preparation), tips for getting children to eat healthier, weight management, and tips on feeding children when they are sick. Additionally, parentsâ preferred methods of obtaining nutrition information were mail, website, class, and other methods such as email. Parentsâ preferred professional sources were pediatricians, dentists, other health professionals, and organizations like the Supplemental Nutrition Program for Women, Infants, and Children (WIC), Supplemental Nutrition Assistance Program (SNAP) or the Boys and Girls Club. In conclusion, this qualitative research gathered information from Latino parents of school-aged children to learn more about drink choices in the Latino households as well as their preference of method and source for obtaining nutrition education. Findings from this study may be useful to create additional nutritional education resources and thus may help meet the needs of the Latino comm
Microbiological control of alcoholic fermentation
Alcoholic fermentation and the production of wine has accompanied humanity for more than 10000 years. However, it has been only in the last 50 years when the winemakers have had the tools to manage and control the process. The methodology to analyze and monitor the succession of the microorganisms that participate in the process along with the effective use of antimicrobial compounds (for instance sulfur dioxide), the control of the temperature and, above all, the use of cellar-friendly fermentation starters (mostly as Active Dry Wine Yeast) have provided the appropriate conditions for that control. However, the use of a limited number of commercial presentations of the starters has generated an unwanted uniformity of the wines produced. Furthermore, new tendencies in wine making with limited or no human intervention have considered these tolls as a negative aspect in the wine quality, although most of these concerns are only philosophical, without clear scientific evidence. We present a revision of the present state of the art in these methodologies where our research group has been working for the last 25 years
Melatonin Minimizes the Impact of Oxidative Stress Induced by Hydrogen Peroxide in Saccharomyces and Non-conventional Yeast
Melatonin (N-acetyl-5-methoxytryptamine) is synthesized from tryptophan by Saccharomyces cerevisiae and non-conventional yeast species. Antioxidant properties have been suggested as a possible role of melatonin in a S. cerevisiae wine strain. However, the possible antioxidant melatonin effect on non-Saccharomyces species and other strains of S. cerevisiae must be evaluated. The aim of this study was to determine the antioxidant capacity of melatonin in eight S. cerevisiae strains and four non-conventional yeasts (Torulaspora delbrueckii, Metschnikowia pulcherrima, Starmerella bacillaris, and Hanseniaspora uvarum). Therefore, the ROS formation, lipid peroxidation, catalase activity, fatty acid composition, and peroxisome proliferation were investigated. The results showed that the presence of melatonin increases peroxisome accumulation and slightly increases the catalase activity. When cells grown in the presence of melatonin were exposed to oxidative stress induced by H2O2, lower ROS accumulation and lipid peroxidation were observed in all tested strains. Therefore, the increased catalase activity that was a consequence of oxidative stress was lower in the presence of melatonin. Moreover, the presence of MEL modulates cell FA composition, increasing oleic and palmitoleic acids and leading to higher UFA/SFA ratios, which have been previously related to a higher tolerance to H2O2. These findings demonstrate that melatonin can act as an antioxidant compound in both S. cerevisiae and non-Saccharomyces yeasts
Analysis of the NCR Mechanisms in Hanseniaspora vineae and Saccharomyces cerevisiae During Winemaking
There is increasing interest in the use of non-Saccharomyces yeasts in winemaking due to their positive attributes. The non-Saccharomyces yeast Hanseniaspora vineae is an apiculate yeast that has been associated with the production of wine with good fermentation capacity and an increase in aromatic properties. However, this yeast represents a concern in mixed culture fermentation because of its nutrient consumption, especially nitrogen, as its mechanisms of regulation and consumption are still unknown. In this study, we analyzed the nitrogen consumption, as well as the nitrogen catabolism repression (NCR) mechanism, in two genome-sequenced H. vineae strains, using synthetic must fermentations. The use of synthetic must with an established nitrogen content allowed us to study the NCR mechanism in H. vineae, following the amino acid and ammonia consumption, and the expression of genes known to be regulated by the NCR mechanism in S. cerevisiae, AGP1, GAP1, MEP2, and PUT2. H. vineae exhibited a similar amino acid consumption and gene expression profile to S. cerevisiae. However, the wine strain of S. cerevisiae QA23 consumed ammonia and valine more quickly and, in contrast, tyrosine and tryptophan more slowly, than the H. vineae strains. Our results showed a similar behavior of nitrogen regulation in H. vineae and S. cerevisiae, indicating the presence of the NCR mechanism in this Hanseniaspora yeast differentiated before the whole genome duplication event of the Saccharomyces complex. Future study will elucidate if the NCR mechanism is the only strategy used by H. vineae to optimize nitrogen consumption
Occurrence of melatonin and indolic compounds derived from L-tryptophan yeast metabolism in fermented wort and commercial beers
Melatonin and serotonin are bioactive compounds present in foods and beverages and related to neuroprotection and anti-angiogenesis, among other activities. They have been described in wines and the role of yeast in their formation is clear. Thus, this study evaluates the content of these bioactives and other related indolic compounds in beer. For this purpose, commercial beers were analyzed by a validated UHPLC-HRMS method and sample treatment optimized due to the low concentrations expected. Moreover, a wort was fermented with different commercial beer yeast (Abbaye, Diamond, SafAle, SafLager) in order to monitor the formation of these bioactives during the elaboration process. Results show that indolic compounds such as N-acetylserotonin and 3-indoleacetic acid are produced during the alcoholic fermentation of wort. Moreover, the occurrence of four indolic compounds (5-hydroxytryptophan, N-acetylserotonin, 3-indoleacetic acid, L-tryptophan ethyl ester) in commercial beers is reported for the first time.Ministerio de EconomĂa y Competitividad AGL2013-47300-C3-2-R, AGL2016-77505-C3-2-
Cold plasma: a new technology to modify wheat flour functionality
Atmospheric pressure cold plasma has the potential to modify biological chemistry and modulate physical surface properties. Wheat flour was treated by low levels of cold plasma (air, 15 V and 20 V) for 60 or 120 s. There was no change in the total aerobic bacterial count or total mould count as a result of treatment. Treatment did not impact the concentration of total non-starch lipids, or non-polar and glycolipids. However, treatment did reduce total free fatty acids and phospholipids and was dose dependent. Oxidation markers (hydroperoxide value and head space n-hexanal) increased with treatment time and voltage, which confirmed the acceleration of lipid oxidation. Total proteins were not significantly influenced by treatment although there was a trend towards higher molecular weight fractions which indicated protein oxidation and treated flour did produce a stronger dough. This study confirms the potential of cold plasma as a tool to modify flour functionality
Common risk factor approach to address socioeconomic inequality in the oral health of preschool children â a prospective cohort study
Background: Dental caries remains the most prevalent chronic condition in children and a major contributor to poor general health. There is ample evidence of a skewed distribution of oral health, with a small proportion of children in the population bearing the majority of the burden of the disease. This minority group is comprised disproportionately of socioeconomically disadvantaged children. An in-depth longitudinal study is needed to better understand the determinants of child oral health, in order to support effective evidence-based policies and interventions in improving child oral health. The aim of the Study of Mothersâ and Infantsâ Life Events Affecting Oral Health (SMILE) project is to identify and evaluate the relative importance and timing of critical factors that shape the oral health of young children and then to seek to evaluate those factors in their inter-relationship with socioeconomic influences.Methods/Design: This investigation will apply an observational prospective study design to a cohort ofsocioeconomically-diverse South Australian newborns and their mothers, intensively following these dyads as the children grow to toddler age. Mothers of newborn children will be invited to participate in the study in the early post-partum period. At enrolment, data will be collected on parental socioeconomic status, mothersâ general and dental health conditions, details of the pregnancy, infant feeding practice and parental health behaviours and practices. Data on diet and feeding practices, oral health behaviours and practices, and dental visiting patterns will be collected at 3, 6, 12 and 24 months of age. When children turn 24-30 months, the children and their mothers/primary care givers will be invited to an oral examination to record oral health status. Anthropometric assessment will also be conducted.Discussion: This prospective cohort study will examine a wide range of determinants influencing child oral health and related general conditions such as overweight. It will lead to the evaluation of the inter-relationship among main influences and their relative effect on child oral health. The study findings will provide high level evidence of pathways through which socio-environmental factors impact child oral health. It will also provide an opportunity to examine the relationship between oral health and childhood overweight.Discussion: This prospective cohort study will examine a wide range of determinants influencing child oral health and related general conditions such as overweight. It will lead to the evaluation of the inter-relationship among main influences and their relative effect on child oral health. The study findings will provide high level evidence of pathways through which socio-environmental factors impact child oral health. It will also provide an to examine the relationship between oral health and childhood overweight
Systematic Collaborative Reanalysis of Genomic Data Improves Diagnostic Yield in Neurologic Rare Diseases
Altres ajuts: Generalitat de Catalunya, Departament de Salut; Generalitat de Catalunya, Departament d'Empresa i Coneixement i CERCA Program; Ministerio de Ciencia e Innovación; Instituto Nacional de Bioinformåtica; ELIXIR Implementation Studies (CNAG-CRG); Centro de Investigaciones Biomédicas en Red de Enfermedades Raras; Centro de Excelencia Severo Ochoa; European Regional Development Fund (FEDER).Many patients experiencing a rare disease remain undiagnosed even after genomic testing. Reanalysis of existing genomic data has shown to increase diagnostic yield, although there are few systematic and comprehensive reanalysis efforts that enable collaborative interpretation and future reinterpretation. The Undiagnosed Rare Disease Program of Catalonia project collated previously inconclusive good quality genomic data (panels, exomes, and genomes) and standardized phenotypic profiles from 323 families (543 individuals) with a neurologic rare disease. The data were reanalyzed systematically to identify relatedness, runs of homozygosity, consanguinity, single-nucleotide variants, insertions and deletions, and copy number variants. Data were shared and collaboratively interpreted within the consortium through a customized Genome-Phenome Analysis Platform, which also enables future data reinterpretation. Reanalysis of existing genomic data provided a diagnosis for 20.7% of the patients, including 1.8% diagnosed after the generation of additional genomic data to identify a second pathogenic heterozygous variant. Diagnostic rate was significantly higher for family-based exome/genome reanalysis compared with singleton panels. Most new diagnoses were attributable to recent gene-disease associations (50.8%), additional or improved bioinformatic analysis (19.7%), and standardized phenotyping data integrated within the Undiagnosed Rare Disease Program of Catalonia Genome-Phenome Analysis Platform functionalities (18%)
ClinPrior: an algorithm for diagnosis and novel gene discovery by network-based prioritization
BackgroundWhole-exome sequencing (WES) and whole-genome sequencing (WGS) have become indispensable tools to solve rare Mendelian genetic conditions. Nevertheless, there is still an urgent need for sensitive, fast algorithms to maximise WES/WGS diagnostic yield in rare disease patients. Most tools devoted to this aim take advantage of patient phenotype information for prioritization of genomic data, although are often limited by incomplete gene-phenotype knowledge stored in biomedical databases and a lack of proper benchmarking on real-world patient cohorts.MethodsWe developed ClinPrior, a novel method for the analysis of WES/WGS data that ranks candidate causal variants based on the patient's standardized phenotypic features (in Human Phenotype Ontology (HPO) terms). The algorithm propagates the data through an interactome network-based prioritization approach. This algorithm was thoroughly benchmarked using a synthetic patient cohort and was subsequently tested on a heterogeneous prospective, real-world series of 135 families affected by hereditary spastic paraplegia (HSP) and/or cerebellar ataxia (CA).ResultsClinPrior successfully identified causative variants achieving a final positive diagnostic yield of 70% in our real-world cohort. This includes 10 novel candidate genes not previously associated with disease, 7 of which were functionally validated within this project. We used the knowledge generated by ClinPrior to create a specific interactome for HSP/CA disorders thus enabling future diagnoses as well as the discovery of novel disease genes.ConclusionsClinPrior is an algorithm that uses standardized phenotype information and interactome data to improve clinical genomic diagnosis. It helps in identifying atypical cases and efficiently predicts novel disease-causing genes. This leads to increasing diagnostic yield, shortening of the diagnostic Odysseys and advancing our understanding of human illnesses
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