Culturable yeast community associated with grape must and honey bees sampled from apiaries located in the vineyards.

Aim: In this study, we investigated culturable yeast community, present in grape must sampled from vineyards with apiaries on the borders, and in honey bees collected in these apiaries.

Methods And Results: To this aim, yeasts isolated from spontaneously fermented grapes randomly collected in two vineyards (P1 and P2) with apiaries on the borders (A1 and A2) were compared to those isolated from spontaneously fermented grapes collected from a vineyard without apiary (P4). At the same time, yeast community was analyzed on bees collected in each apiary placed in the vineyards, in comparison to yeasts isolated from an apiary (A3) located far from the vineyards.

Preliminary investigation on the potential involvement of an ABC-like gene in Halomicronema metazoicum (Cyanobacteria) tolerance to low seawater pH in an ocean acidification scenario.

Decreasing ocean surface pH, called ocean acidification (OA), is among the major risks for marine ecosystems due to human-driven atmospheric pCO increase. Understanding the molecular mechanisms of adaptation enabling marine species to tolerate a lowered seawater pH could support predictions of consequences of future OA scenarios for marine life. This study examined whether the ATP-binding cassette (ABC)-like gene slr2019 confers tolerance to the marine cyanobacterium Halomicronema metazoicum to low seawater pH conditions (7.

Screening of and Non- Wine Yeasts for Their Decarboxylase Activity of Amino Acids.

The type and quantity of precursor amino acids present in grape must that are used by wine yeasts affect the organoleptic and health properties of wine. The aim of this work was to conduct a preliminary screening among and non- indigenous strains, which were previously isolated from different Italian regional grape varieties. This was performed in order to evaluate their decarboxylase activity on certain important amino acids-such as arginine, proline, serine, and tyrosine-that are present in grape must.

Impact of Starmerella bacillaris and Zygosaccharomyces bailii on ethanol reduction and Saccharomyces cerevisiae metabolism during mixed wine fermentations.

The bulk of grape juice fermentation is carried out by the yeast Saccharomyces cerevisiae, but non-Saccharomyces yeasts can modulate many sensorial aspects of the final products in ways not well understood. In this study, some of such non-conventional yeasts were screened as mixed starter cultures in a defined growth medium in both simultaneous and sequential inoculations. One strain of Starmerella bacillaris and another of Zygosaccharomyces bailii were chosen by their distinct phenotypic footprint and their ability to reduce ethanol levels at the end of fermentation.

Role of Yeasts on the Sensory Component of Wines.

The aromatic complexity of a wine is mainly influenced by the interaction between grapes and fermentation agents. This interaction is very complex and affected by numerous factors, such as cultivars, degree of grape ripeness, climate, mashing techniques, must chemical−physical characteristics, yeasts used in the fermentation process and their interactions with the grape endogenous microbiota, process parameters (including new non-thermal technologies), malolactic fermentation (when desired), and phenomena occurring during aging. However, the role of yeasts in the formation of aroma compounds has been universally recognized.

In Vitro Study of Probiotic, Antioxidant and Anti-Inflammatory Activities among Indigenous Strains.

Nowadays, the interest toward products containing probiotics is growing due to their potential health benefits to the host and the research is focusing on search of new probiotic microorganisms. The present work was focused on the characterization of indigenous strains, isolated from different food matrixes, with the goal to select strains with probiotic or health-beneficial potential. A preliminary screening performed on fifty indigenous strains, in comparison to a commercial probiotic strain, allowed to individuate the most suitable ones for potential probiotic aptitude.

Validation of a Standard Protocol to Assess the Fermentative and Chemical Properties of Wine Strains.

This paper reports on a common experiment performed by 17 Research Units of the Italian Group of Microbiology of Vine and Wine (GMVV), which belongs to the Scientific Society SIMTREA, with the aim to validate a protocol for the characterization of wine strains of . For this purpose, two commercial strains (EC 1118 and AWRI796) were used to carry out inter-laboratory-scale comparative fermentations using both synthetic medium and grape musts and applying the same protocol to obtain reproducible, replicable, and statistically valid results. Ethanol yield, production of acetic acid, glycerol, higher alcohols, and other volatile compounds were assessed.

Corrigendum: Genome Sequencing and Comparative Analysis of Three Indigenous Wine Strains Reveal Remarkable Biotechnological Potential.

[This corrects the article DOI: 10.3389/fmicb.2019.

Saccharomyces cerevisiae and Hanseniaspora uvarum mixed starter cultures: Influence of microbial/physical interactions on wine characteristics.

The growing trend in the wine industry is the revaluation of the role of non-Saccharomyces yeasts, promoting the use of these yeasts in association with Saccharomyces cerevisiae. Non-Saccharomyces yeasts contribute to improve wine complexity and organoleptic composition. However, the use of mixed starters needs to better understand the effect of the interaction between these species during alcoholic fermentation.

Biotechnological Approach Based on Selected Starters for Reducing the Use of Sulfur Dioxide in Wine.

Sulfites are considered the main additives in winemaking for their antimicrobial, antioxidant and anti-oxidasic activities. The current concern about the potential negative effects of sulfur dioxide (SO) on consumer health has focused the interest on replacing or reducing SO use. Our work aims to develop a strategy based on the use of selected starter culture, able to perform wine fermentation without SO addition.

Genome Sequencing and Comparative Analysis of Three Indigenous Wine Strains Reveal Remarkable Biotechnological Potential.

A current trend in winemaking has highlighted the beneficial contribution of non- yeasts to wine quality. is one of the more represented non- species onto grape berries and plays a critical role in influencing the wine sensory profile, in terms of complexity and organoleptic richness. In this work, we analyzed a group of indigenous wine strains as for genetic as for technological traits, such as resistance to SO and β-glucosidase activity.

Use of Saccharomyces cerevisiae var. boulardii in co-fermentations with S. cerevisiae for the production of craft beers with potential healthy value-added.

In recent years, the awareness of consumers about the impact of food on health is constantly increasing. A high amount of dietary antioxidant intake can be supplied by beverages widely consumed, such as wine, coffee, beer. Recently, an increase in the consumer interest was observed for beer, in consequence of the high phenolic antioxidants and low ethanol content present in this beverage.

Yeast Starter as a Biotechnological Tool for Reducing Copper Content in Wine.

Copper is widely used in agriculture as a traditional fungicide in organic farming to control downy mildew on grapes, consequently it is possible to find this metal during all stages of the vinification process. Low amounts of copper play a key role on the function of key cell enzymes, whereas excess quantities can exert amount-dependent cytotoxicity, resulting in general cellular damage. Nowadays the excessive copper ions in wines is removed by addition of adsorbents, but these additives can influence the sensory characteristics of wine, as well as detrimental to the health of consumers.

Identification by phenotypic and genetic approaches of an indigenous Saccharomyces cerevisiae wine strain with high desiccation tolerance.

During active dry yeast (ADY) production process, cells are exposed to multiple stresses, such as thermal, oxidative and hyperosmotic shock. Previously, by analysing cells in exponential growth phase, we selected an indigenous Saccharomyces cerevisiae wine strain, namely CD-6Sc, for its higher tolerance to desiccation and higher expression of specific desiccation stress-related genes in comparison to other yeast strains. In this study, we performed a desiccation treatment on stationary phase cells by comparing the efficacy of two different methods: a 'laboratory dry test' on a small scale (mild stress) and a treatment by spray-drying (severe stress), one of the most appropriate preservation method for yeasts and other micro-organisms.

Implementing principles of traditional concentrated grape must fermentation to the production of new generation balsamic vinegars. Starter selection and effectiveness.

In an effort to implement principles of traditional concentrated grape must fermentation to the production of new generation balsamic vinegars (BVs), the specific goals of the study were the isolation and molecular identification of the predominant yeasts in concentrated grape must (cv. Xinomavro), their technological characterization and the evaluation of the fermentative aptitude of the selected strains. Tolerance against 5-hydroxymethyl-furfural (HMF) and furfural, acetic acid and glucose concentration was examined by appropriate methods and tests.

Diversity of Saccharomyces cerevisiae Strains Isolated from Two Italian Wine-Producing Regions.

Numerous studies, based on different molecular techniques analyzing DNA polymorphism, have provided evidence that indigenous Saccharomyces cerevisiae populations display biogeographic patterns. Since the differentiated populations of S. cerevisiae seem to be responsible for the regional identity of wine, the aim of this work was to assess a possible relationship between the diversity and the geographical origin of indigenous S.

Yeast Interactions in Inoculated Wine Fermentation.

The use of selected starter culture is widely diffused in winemaking. In pure fermentation, the ability of inoculated Saccharomyces cerevisiae to suppress the wild microflora is one of the most important feature determining the starter ability to dominate the process. Since the wine is the result of the interaction of several yeast species and strains, many studies are available on the effect of mixed cultures on the final wine quality.

Comparative study of Saccharomyces cerevisiae wine strains to identify potential marker genes correlated to desiccation stress tolerance.

The most diffused formulation of starter for winemaking is active dry yeast (ADY). ADYs production process is essentially characterized by air-drying stress, a combination of several stresses, including thermal, hyperosmotic and oxidative and cell capacity to counteract such multiple stresses will determine its survival. The molecular mechanisms underlying cell stress response to desiccation have been mostly studied in laboratory and commercial yeast strains, but a growing interest is currently developing for indigenous yeast strains which represent a valuable and alternative source of genetic and molecular biodiversity to be exploited.

Indigenous yeast population from Georgian aged wines produced by traditional "Kakhetian" method.

The yeast microbiota present in wines produced by the ancient "Kakhetian" method in Georgia (EU) was studied. This technique involves the use of terracotta vessels (amphoras), during spontaneous fermentation, maceration phase and wine ageing. The analysed yeasts were collected from wines after maturation for one year in ten amphoras from a Georgian winery.

Genetic improvement of Saccharomyces cerevisiae wine strains for enhancing cell viability after desiccation stress.

In the last few decades spontaneous grape must fermentations have been replaced by inoculated fermentation with Saccharomyces cerevisiae strains as active dry yeast (ADY). Among the essential genes previously characterized to overcome the cell-drying/rehydration process, six belong to the group of very hydrophilic proteins known as hydrophilins. Among them, only SIP18 has shown early transcriptional response during dehydration stress.

Bioethanol production from mixed sugars by Scheffersomyces stipitis free and immobilized cells, and co-cultures with Saccharomyces cerevisiae.

Bioethanol can be produced from several biomasses including lignocellulosic materials. Besides 6-carbon sugars that represent the prevalent carbohydrates, some of these feedstocks contain significant amounts of 5-carbon sugars. One common limit of the major part of the xylose-fermenting yeasts is the diauxic shift between the uptake of glucose and xylose during the fermentation of mixed syrups.

Geographical markers for Saccharomyces cerevisiae strains with similar technological origins domesticated for rice-based ethnic fermented beverages production in North East India.

Autochthonous strains of Saccharomyces cerevisiae from traditional starters used for the production of rice-based ethnic fermented beverage in North East India were examined for their genetic polymorphism using mitochondrial DNA-RFLP and electrophoretic karyotyping. Mitochondrial DNA-RFLP analysis of S. cerevisiae strains with similar technological origins from hamei starter of Manipur and marcha starter of Sikkim revealed widely separated clusters based on their geographical origin.

Selection of indigenous Saccharomyces cerevisiae strains for Nero d'Avola wine and evaluation of selected starter implantation in pilot fermentation.

The present research studied Saccharomyces cerevisiae yeasts isolated from Nero d'Avola grapes, collected in different areas of the Sicily region. RAPD-PCR analysis with M13 primer was used for preliminary discrimination among 341 S. cerevisiae isolates.