Wine bioacidification: Fermenting Airén grape juices with Lachancea thermotolerans and Metschnikovia pulcherrima followed by sequential Saccharomyces cerevisiae inoculation.

Biological acidification and bioprotection are interesting tools to overcome some problems of climate change and fit some consumer requirements for fresher wine styles. Juices of Airén (Vitis vinifera L.) were fermented by Lachancea thermotolerans (Lt) and Metschnikowia pulcherrima (Mp) starters and compared with Saccharomyces cerevisiae (Sc).

Development of a model to study browning caused by tyrosinase in grape must.

Enzymatic browning caused by polyphenol oxidases, tyrosinase and laccase, continues to be one of the main problems in winemaking. Therefore, wineries are very interested in studying the mechanisms of browning and procedures for decreasing the use sulphur dioxide. This research proposes a model to study tyrosinase activity from grape must using different substrates: one monophenol (p-hydroxybenzoic acid), two diphenols (caftaric acid and (-)-epicatechin) and one triphenol (gallic acid).

Use of Glutathione, Pure or as a Specific Inactivated Yeast, as an Alternative to Sulphur Dioxide for Protecting White Grape Must from Browning.

One of the problems that most seriously affects oenology today is enzymatic browning, especially when grapes are infected by grey rot. We studied the capacity of glutathione (GSH) and a specific inactivated dry yeast rich in glutathione (IDY-GSH) to protect white grape must from browning compared to that of sulphur dioxide (SO). The results indicate that SO drastically reduces the oxygen consumption rate (by around 72%), protects hydroxycinnamic acids from oxidation and prevents grape must against browning even in the presence of laccase.

Systematic analysis of RhoGEF/GAP localizations uncovers regulators of mechanosensing and junction formation during epithelial cell division.

Cell proliferation is central to epithelial tissue development, repair, and homeostasis. During cell division, small RhoGTPases control both actomyosin dynamics and cell-cell junction remodeling to faithfully segregate the genome while maintaining tissue polarity and integrity. To decipher the mechanisms of RhoGTPase spatiotemporal regulation during epithelial cell division, we generated a transgenic fluorescently tagged library for the 48 Drosophila Rho guanine exchange factors (RhoGEFs) and GTPase-activating proteins (GAPs), and we systematically characterized their endogenous distributions by time-lapse microscopy.

Co-inoculations of Lachancea thermotolerans with different Hanseniaspora spp.: Acidification, aroma, biocompatibility, and effects of nutrients in wine.

The use of non-Saccharomyces yeast in the winemaking industry and even more their co-inoculations to maximize their growth and to express phenotypic characteristic is gaining more and more relevance. This study aimed to shed light on the biocompatibilities between Lachancea thermotolerans and Hanseniaspora spp., using different types of nutrients and considering the effect on Yeast Assimilable Nitrogen (YAN), at low temperature (16 °C) and medium SO (50 mg/L), in white must.

A High-Throughput Search for SFXN1 Physical Partners Led to the Identification of ATAD3, HSD10 and TIM50.

Sideroflexins (SFXN, SLC56) are a family of evolutionarily conserved mitochondrial carriers potentially involved in iron homeostasis. One member of the SFXN family is SFXN1, recently identified as a human mitochondrial serine transporter. However, little is known about the SFXN1 interactome, necessitating a high-throughput search to better characterize SFXN1 mitochondrial functions.

Generation of intra- and interspecific Saccharomyces hybrids with improved oenological and aromatic properties.

Non-wine yeasts could enhance the aroma and organoleptic profile of wines. However, compared to wine strains, they have specific intolerances to winemaking conditions. To solve this problem, we generated intra- and interspecific hybrids using a non-GMO technique (rare-mating) in which non-wine strains of S.

Modulation of aroma and chemical composition of Albariño semi-synthetic wines by non-wine Saccharomyces yeasts and bottle aging.

Saccharomyces yeasts from different origins and species fermented in a semi-synthetic must containing aroma precursor of cv. Albariño and polyfunctional mercaptans precursors. The resulting wines were subjected to accelerate anoxic aging.

Effect of non-wine Saccharomyces yeasts and bottle aging on the release and generation of aromas in semi-synthetic Tempranillo wines.

Interest in the use of non-conventional yeasts in wine fermentation has been increased in the last years in the wine sector. The main objective of this manuscript was to explore the aromatic diversity produced by wild and non-wine strains of S. cerevisiae, S.

Impact of Nitrogen Addition on Wine Fermentation by Strains with Different Nitrogen Requirements.

In modern oenology, supplementation of nitrogen sources is an important strategy to prevent sluggish or stuck fermentation. The present study thoroughly determined the effect of nitrogen addition timing and nitrogen source type on fermentation kinetics and aroma production, carried out by yeast strains with low and high nitrogen requirements. The results revealed that yeast strains with different nitrogen requirements have divergent reactions to nitrogen addition.

Biocompatibility in Ternary Fermentations With , Other Non- and to Control pH and Improve the Sensory Profile of Wines From Warm Areas.

Global warming is causing serious problems, especially, in warm regions, where musts with excess sugars and high pH produce wines with decreased freshness and unstable evolution. This study aimed to determine biocompatibility between yeast species, the capacity for microbiological acidification, and the aromatic profile produced in ternary fermentations in which has been co-inoculated with , , or , and the fermentation process is subsequently completed with sequential inoculation of . For this purpose, different cell culture media and instruments were used such as infrared spectroscopy, enzymatic autoanalyzer, chromatograph coupled with a flame ionization detector, spectrophotometric analysis, among others.

The effects of strains carrying alcoholic fermentation on the fermentative and varietal aroma profiles of young and aged Tempranillo wines.

Ten different strains fermented semi-synthetic musts containing a Polyphenolic and Aroma Precursor Fraction (PAF) extracted from Tempranillo grapes. Aroma compounds were studied by Gas Chromatography (GC), GC-Olfactometry and GC-Mass Spectrometry (MS), during fermentation by trapping volatilized aroma, immediately after fermentation and after accelerated aging. Volatiles lost by evaporation during fermentation are mostly fermentative compounds and not grape-related odorants.

Screening of Saccharomyces strains for the capacity to produce desirable fermentative compounds under the influence of different nitrogen sources in synthetic wine fermentations.

A collection of 33 Saccharomyces yeasts were used for wine fermentation with a sole nitrogen source: ammonium and four individual aroma-inducing amino acids. The fermentation performance and chemical wine composition were evaluated. The most valuable nitrogen sources were valine as a fermentation promoter on non-cerevisiae strains, phenylalanine as fruity aromas enhancer whereas the ethanol yield was lessened by leucine and isoleucine.

Thermo-adaptive evolution to generate improved Saccharomyces cerevisiae strains for cocoa pulp fermentations.

Cocoa pulp fermentation is a consequence of the succession of indigenous yeasts, lactic acid bacteria and acetic acid bacteria that not only produce a diversity of metabolites, but also cause the production of flavour precursors. However, as such spontaneous fermentations are less reproducible and contribute to produce variability, interest in a microbial starter culture is growing that could be used to inoculate cocoa pulp fermentations. This study aimed to generate robust S.

Phenotypic and genomic differences among S. cerevisiae strains in nitrogen requirements during wine fermentations.

Nitrogen requirements by S. cerevisiae during wine fermentation are highly strain-dependent. Different approaches were applied to explore the nitrogen requirements of 28 wine yeast strains.

Insights into the Roles of the Sideroflexins/SLC56 Family in Iron Homeostasis and Iron-Sulfur Biogenesis.

Sideroflexins (SLC56 family) are highly conserved multi-spanning transmembrane proteins inserted in the inner mitochondrial membrane in eukaryotes. Few data are available on their molecular function, but since their first description, they were thought to be metabolite transporters probably required for iron utilization inside the mitochondrion. Such as numerous mitochondrial transporters, sideroflexins remain poorly characterized.

Isotopic Tracers Unveil Distinct Fates for Nitrogen Sources during Wine Fermentation with Two Non- Strains.

Non- yeast strains have become increasingly prevalent in the food industry, particularly in winemaking, because of their properties of interest both in biological control and in complexifying flavour profiles in end-products. However, unleashing the full potential of these species would require solid knowledge of their physiology and metabolism, which is, however, very limited to date. In this study, a quantitative analysis using N-labelled NHCl, arginine, and glutamine, and C-labelled leucine and valine revealed the specificities of the nitrogen metabolism pattern of two non- species, and In , consumed nitrogen sources were mainly directed towards the synthesis of proteinogenic amino acids, at the expense of volatile compounds production.

Industrial Performance of Several Strains for pH Control in White Wines from Warm Areas.

In the current scenario of climatic warming, the over-ripening of grapes increases the sugar content, producing flat and alcoholic wines with low acidity, high pH and low freshness. Additionally, a high pH makes wines more chemically and microbiologically unstable, requiring a higher sulphite content for preservation. Some strains of can naturally lower the pH of wine by producing lactic acid from sugars; this pH reduction can reach 0.

Differential Contribution of the Parental Genomes to a × Hybrid, Inferred by Phenomic, Genomic, and Transcriptomic Analyses, at Different Industrial Stress Conditions.

In European regions of cold climate, can replace in wine fermentations performed at low temperatures. is a cryotolerant yeast that produces more glycerol, less acetic acid and exhibits a better aroma profile. However, this species exhibits a poor ethanol tolerance compared with .

Nitrogen sources preferences of non-Saccharomyces yeasts to sustain growth and fermentation under winemaking conditions.

Wine-related non-Saccharomyces yeasts are becoming more widely used in oenological practice for their ability to confer wine a more complex satisfying aroma, but their metabolism remains unknown. Our study explored the nitrogen utilisation profile of three popular non-Saccharomyces species, Torulaspora delbrueckii, Metschnikowia pulcherrima and Metschnikowia fructicola. The nitrogen source preferences to support growth and fermentation as well as the uptake order of different nitrogen sources during wine fermentation were investigated.

The Hox gene controls appendage shape by regulating extracellular matrix dynamics.

Although the specific form of an organ is frequently important for its function, the mechanisms underlying organ shape are largely unknown. In , the wings and halteres, homologous appendages of the second and third thoracic segments, respectively, bear different forms: wings are flat, whereas halteres are globular, and yet both characteristic shapes are essential for a normal flight. The Hox gene () governs the difference between wing and haltere development, but how function in the appendages prevents or allows flat or globular shapes is unknown.

Yeast influence on the formation of stable pigments in red winemaking.

The anthocyanin profile of a wine greatly varies over time depending on many factors. In addition to color modifications due to changes in the chemical composition of wine, there may be some influence of the yeast strain used in fermentation. The main aim of this study is to identify and quantify the different ways in which yeast may influence on wine color and its stability, during red winemaking.

A functional antagonism between the pgc germline repressor and torso in the development of somatic cells.

Segregation of the germline is a fundamental event during early development. In Drosophila, germ cells are specified at the posterior pole of the embryo by the germplasm. As zygotic expression is activated, germ cells remain transcriptionally silent owing to the polar granule component (Pgc), a small peptide present in germ cells.

Simple and rapid characterization of soybean cultivars by perfusion reversed-phase HPLC: application to the estimation of the 11S and 7S globulin contents.

A perfusion RP HPLC method enabling the separation of soybean proteins in an analysis time lower than 3 min has been used to obtain the chromatographic profiles of different soybean cultivars. The chromatograms obtained for each soybean variety presented clear differences that justified the potential use of this method for cultivar characterization. The area percentages obtained were employed as variables for cluster and principal components analysis of these soybeans.

Spatially distinct downregulation of Capicua repression and tailless activation by the Torso RTK pathway in the Drosophila embryo.

Specification of the terminal regions of the Drosophila embryo depends on the Torso RTK pathway, which triggers expression of the zygotic genes tailless and huckebein at the embryonic poles. However, it has been shown that the Torso signalling pathway does not directly activate expression of these zygotic genes; rather, it induces their expression by inactivating, at the embryonic poles, a uniformly distributed repressor activity. In particular, it has been shown that Torso signalling regulates accumulation of the Capicua transcriptional repressor: as a consequence of Torso signalling Capicua is downregulated specifically at the poles of blastoderm stage embryos.