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Grapes have a complex microbial ecology including filamentous fungi, yeasts and bacteria with different physiological characteristics and effects upon wine production. Some species are only found in grapes, such as parasitic fungi and environmental bacteria, while others have the ability to survive and grow in wines, constituting the wine microbial consortium. The aim of the present study was to identify bacteria and yeasts in grape samples from Slovakia. A total amount of 13 grapes, or more precisely 9 white and 4 red were collected from August until November 2021, from a local Slovak winemaker, including 1. Irsai Olivér, 2. Feteasca regala, 3. Chardonnay, 4. Green Veltliner, 5. Mūller Thurgau, 6. Palava, 7. Rhein Riesling, 8. Welschriesling, 9. Sauvignon Blanc, 10. Alibernet, 11. Blue Frankish, 12. Cabernet Sauvignon, and 13. Dornfelder grapes samples were also used in our study. The microorganisms were cultivated on following way: at 25 0C for five days aerobically on malt extract agar (MEA) for yeasts, at 37 0C for 24 - 48 h aerobically on plate count agar (PCA) for total count of bacteria, and at 30 0C for 48 - 72 hour microaerophilic on de Man, Rogosa and Sharpe agar (MRS) for lactic acid bacteria. MALDI-TOF MS Biotyper mass spectrometry was used for identification of bacteria and yeasts, and microscopic filamentous fungi were identified via Samson, Samson and Frisvad and Pitt and Hocking manuals. A total of 152 isolates were identified with mass spectrometry. Total bacterial counts on different wine grape berries ranged from 2.32 ± 0.05 in to 5.21 ± 0.02 log CFU x g-1. Lactic acid bacteria ranged from 3.22 ± 0.06 to 3.96 ± 0.07 log CFU x g-1. Yeast count ranged from 1.25 ± 0.04 to 3.11 ± 0.09 log CFU x g-1. The most identified yeast species were Hanseniaspora uvarum and Priestia megatherium, and Lactococcus lactis for bacteria. Natural microbiota of grape berries is very diverse. In our study, the bacterial species were the most isolated microorganisms. [ABSTRACT FROM AUTHOR]

Chemical fertilizers were applied on perennial tree vines to obtain high yields, which have resulted in considerable deterioration of soil quality, and it is likely to have negative impacts on the development of the grape industry. In this study, P. putida Rs-198 liquid biofertilizer (Rs198LBF) was inoculated into grape rhizosphere soils to assess its influence on grape growth and microbial community. Field experiment results showed that grape growth and quality increased depending on the concentrations of Rs198LBF applications. The berry weight, length, and width in addition with 60 ml Rs198LBF (1.44 × 10 13 cfu m l − 1 Rs-198) per grapevine treatment (BFP3) were 17.2%, 6.2%, and 4.4% higher than those of CK (control, non-inoculation) treatment, respectively. The available phosphorus contents in addition with 40 ml Rs198LBF per grapevine (BFP2) and BFP3 treatments were 12.6% and 55.3% higher than those of CK treatment (P < 0.05). The activities of invertase and alkaline phosphatase were improved in BFP2 and BFP3 treatment compared with those in CK. The relative abundance of potentially beneficial bacteria significantly increased compared with that in CK treatment (P < 0.05). The clusters of orthologous groups (COG) annotation illustrated that the application of 60 ml Rs198LBF increased the relative abundance of metabolic genes in rhizosphere soil. The results of this study show that biofertilizer is very effective in enhancing plant growth and affects soil community diversity. [ABSTRACT FROM AUTHOR]

The in vitro and in situ antifungal activity of Lactobacillus plantarum against the ochratoxigenic fungus Aspergillus carbonarius was investigated in this study. Four different fungal isolates from grape berries were co-cultured with four different strains of L. plantarum on Malt Extract Agar (MEA) plates at 30 °C. Bacterial strains inhibited fungal growth up to 88% and significantly reduced toxin production up to 100%. In addition, L . plantarum was evaluated as biocontrol agent against A . carbonarius growth and OTA production on table grapes. Temporal studies of bacterial antagonism were performed with two different grape cultivars. Artificially wounded and unwounded berries were pre-treated with 10 8  CFU/mL bacteria and inoculated with 10 6  spores/mL of A . carbonarius ochratoxigenic isolates. Biocontrol agents displayed high rate of colonization on grapes during 5 days of incubation at 30 °C. Scanning electron microscopy (SEM) also determined the presence of microorganisms on grape surface. Bacterial strains were effective in controlling fungal infection reaching up to 71% inhibition rates. However the presence of wounds on grape skin facilitated infection of berries by A . carbonarius , since unwounded berries showed lower levels of infection. Results also revealed significant reduction in mycotoxin production ranging between 32% and 92%. Transcriptome analysis following exposure to co-cultivation, exhibited differential expression for each gene studied of AcOTA nrps ( Aspergillus carbonarius OTA nonribosomal), AcOT Apks ( Aspergillus carbonarius OTA polyketide synthase ) and laeA , emphasizing the significance of strain variability. The genes AcOTA nrps and laeA were most influenced by the presence of L. plantarum . This work is a contribution for the potential biocontrol of toxigenic fungi in table grapes by lactic acid bacteria (LAB). The above findings underline the significance of bacterial strain variability on the effectiveness of biopreservative features of L. plantarum strains. [ABSTRACT FROM AUTHOR]

The influence of the matrix and the concentration of the pesticides on the bioavailability of the dimethomorph, ametoctradin, boscalid, fenhexamid, mepanipyrim, cyazofamid, kresoxim-methyl, pyraclostrobin, and metrofenone fungicides in grapes and red wine are studied. Bioavailability is calculated using an in vitro procedure and by simulating human gastric digestion by dialyzation of the fungicides at six concentrations (0.1, 0.5, 1, 2, 5, and 10 mg kg−1) in the semipermeable cellulose membrane. Analyses were carried out by QuEChERS extraction method and liquid chromatography with mass spectrometry with a triple quadrupole analyzer detection (LC-MS/MS QqQ). The results indicated a clear effect of the concentration and matrix, with dialyzation in grapes and red wine beginning in some fungicides from just 2 mg kg1, and in water from 5 mg kg−1. The different matrices can also be ordered according to the matrix effect: water > red wine > grape. The fungicides which present greatest bioavailability are, in order: ametoctradin in grape and red wine, boscalid in red wine and water, dimethomorph in water, and fenhexamid in red wine and water. [ABSTRACT FROM AUTHOR]

Fertilisation practices are increasingly recognised as factors influencing the soil microbial communities, and they have a pivotal role in maintaining soil fertility and regulating ecosystem functions. Soil microbial communities react to different fertilisation practices and environmental conditions. It is known that vineyards harbour a specific set of microorganisms. The vineyard microbiome has been extensively investigated to decipher the associated microbial populations in soil, as well as the dynamics of microorganisms in grapes and the phyllosphere. Wine harbours a wide range of microorganisms originating from the belowground environment, many of which are recognised for their role in driving the grapevine quality. This study evaluates the long term-effect of two fertilisation practices (mineral, MD and organo-mineral, OMD) on the soil bacterial community in a nine-year-old vineyard. Sequencing was done on environmental DNA soil samples to amplify the hypervariable region V3–V4 of the 16S rRNA gene using an Illumina platform. The results provide information on the distribution of different bacterial groups in relation to fertilisation practices and temporal variability. Our work reveals that the assortment and distribution of microorganisms in agricultural systems depend on several factors, underlining the importance of fertilisation strategy in the overall management of soil quality and fertility. [ABSTRACT FROM AUTHOR]

The lignocellulosic structure of grape pomace requires the use of pretreatments facilitating microbial decomposition of the matter and enhancing methane production. In this study, the effects of various pretreatments (freezing, alkaline treatment using NaOH and NH 3 , acid treatment using HCl, ultrasounds and pulsed electric fields) were examined in batch mode. The highest methane production (0.178 Nm 3 kg −1 of COD) was attained after alkaline treatment with 10% NaOH w/w dry basis, at 20 °C and for 24 h. This result is due to the degradation of more than 50% of lignin and about 22% of cellulose present in grape pomace. The coupling of this pretreatment with freezing at −20 °C exhibited the highest methane production of 0.2194 ± 0.0007 Nm 3 kg −1 of COD. When applied to a larger scale continuous digester, this coupled pretreatment increased methane production by about 27%, compared to the untreated samples, promoting the green valorization of the biomass. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the biodiversity of Aspergillus section Nigri populations from Cyprus vineyards by morphological, toxigenic and phylogenetic analysis. Aspergillus section Nigri populations were isolated from grapes of the varieties ‘Maratheftiko’ and ‘Cabernet Sauvignon’ originating from six growing regions of Cyprus during 2010 and 2011 years. The isolation frequency of Aspergillus section Nigri from grape samples was 43.3% and a total of 284 isolates were selected for further analyses based on the macroscopic characteristics of black aspergilli. The isolates were characterized by sequencing analysis of the calmodulin gene in order to identify species responsible for ochratoxin A (OTA) production. The phylogenetic analysis showed that the isolates were grouped in three major clusters. The A. tubingensis cluster included 262 isolates (92.25%), the A. niger cluster included 15 isolates identified as A. niger (5.3%) and 6 isolates identified as A. welwitschiae (2.1%). One isolate was classified as A. carbonarius (0.35%) and was grouped in a cluster together with the reference isolates of A. carbonarius , A. sclerotioniger , A. sclerotiocarbonarius and A. ibericus . All the isolates were evaluated for their ochratoxigenic ability by HPLC coupled with a fluorescence detector (HPLC-FLD) and the positive isolates were re-examined using ultra high-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). The Aspergillus carbonarius isolate produced an average quantity of 1436.1 ng OTA/g Czapek Yeast Agar (CYA); From the A. niger strains three isolates (20%) produced OTA and only one isolate from A. welwitschiae (16.7%) was proved ochratoxigenic with toxin production average at 23.9 ng/g and 9.1 ng/g CYA respectively. Grape must samples derived from the collected berries were also analyzed for OTA and none of the samples were found contaminated with the mycotoxin. The results showed that the geographic area and the meteorological conditions had no significant effect on the incidence and the distribution of black aspergilli in this 2-year project. However, absence of rainfall and low humidity during the harvesting period were critical for the low incidence of the ochratoxigenic A. carbonarius on grapes. [ABSTRACT FROM AUTHOR]

Grape berries harbor a wide range of microbes originating from the vineyard environment, many of which are recognized for their role in the must fermentation process shaping wine quality. To better clarify the contribution of the microbiome of grape fruits during wine fermentation, we used high-throughput sequencing to identify bacterial and fungi communities associated with berries and musts of Cannonau. This is the most important cultivar-wine of Sardinia (Italy) where most vineyards are cultivated without phytochemical treatments. Results suggested that microbiomes of berries collected at four different localities share a core composition characterized by Enterobacteriales, Pseudomonadales, Bacillales, and Rhodospirillales. However, any area seems to enrich berries microbiome with peculiar microbial traits. For example, berries belonging to the biodynamic vineyards of Mamoiada were rich in Bacillales typical of manure (i.e. Lysinibacillus, Bacillus, and Sporosarcina), whereas in the Santadi locality, berries showed soil bacteria such as Pasteurellales and Bacteroidales as well as Rhodospirillales and Lactobacillales which are commonly involved in wine fermentation. In the case of fungi, the most abundant taxa were Dothioraceae, Pleosporaceae, and Saccharomycodaceae, and although the proportion of these families varied among localities, they occurred ubiquitously in all vineyards. During vinification processes performed at the same wine cellar under controlled conditions and without using any yeast starter, more than 50% of bacteria groups of berries reached musts, and each locality had its own private bacteria signature, even if Saccharomyces cerevisiae represented the most abundant fungal species. This work suggests that natural berries microbiome could be influenced by pedoclimatic and anthropologic conditions (e.g., farming management), and the fruits’ microorganisms persist during the fermentation process. For these reasons, a reliable wine genotyping should include the entire holobiont (plant and all its symbionts), and bioprospecting activities on grape microbiota could lead to improved viticulture yields and wine quality. [ABSTRACT FROM AUTHOR]

Binding of anthocyanin extract from grapes ( Fetească neagră variety) by whey protein isolate was first estimated through fluorescence spectroscopy quenching experiments. The data were analyzed using the modified Stern-Volmer equation, allowing the estimation of binding and thermodynamic parameters. The increase of binding constants, accessible fractions, and number of binding sites was highlighted when increasing the temperature, suggesting the presence of the dynamic quenching process. The HPLC analysis allowed the identification of anthocyanin composition of extract and powders, highlighting the presence of the malvidin-3-glucoside as the main anthocyanin. Molecular docking tests provided strong evidence on the involvement of α-lactalbumin and β-lactoglobulin in the tight binding of malvidin-3-glucoside. Further, grape anthocyanins were encapsulated within whey protein isolate and two different polysaccharides (acacia gum and pectin) by coacervation, followed by freeze-drying. The encapsulating efficiency varied between 94 and 99%. Two size smaller particles were obtained in case of microencapsulation in the presence of pectin when compared with acacia gum, as revealed by laser confocal scanning microscopy investigations. Significantly, the experimental variant with pectin allowed the entrapment of a higher amount of flavonoids. The antioxidant activities of the two experimental variants were comparable. The thermal stability experiments evidenced a relatively higher protective effect on anthocyanin degradation in the variant with pectin. [ABSTRACT FROM AUTHOR]

This study aimed at using grape marc for the growth of lactic acid bacteria and bifidobacteria with the perspective of producing a functional ingredient having antioxidant activity. Lactobacillus plantarum 12A and PU1, Lactobacillus paracasei 14A, and Bifidobacterium breve 15A showed the ability to grow on grape marc (GM) based media. The highest bacterial cell density (>9.0 CFU/g) was found in GM added of 1% of glucose (GMG). Compared to un-inoculated and incubated control fermented GMG showed a decrease of carbohydrates and citric acid together with an increase of lactic acid. The content of several free amino acids and phenol compounds differed between samples. Based on the survival under simulated gastro-intestinal conditions, GMG was a suitable carrier of lactic acid bacteria and bifidobacteria strains. Compared to the control, cell-free supernatant (CFS) of fermented GMG exhibited a marked antioxidant activity in vitro . The increased antioxidant activity was confirmed using Caco-2 cell line after inducing oxidative stress, and determining cell viability and radical scavenging activity through MTT and DCFH-DA assays, respectively. Supporting these founding, the SOD-2 gene expression of Caco-2 cells also showed a lowest pro-oxidant effect induced by the four CFS of GMG fermented by lactic acid bacteria and bifidobacteria. [ABSTRACT FROM AUTHOR]

Oenococcus oeni is the main lactic acid bacteria species associated with grapes and wine. It is a bacterium that has adapted itself to the harsh conditions of wine, and demonstrated its importance in the production of quality wines. It has a small genome (1.8 Mb); over 200 strains have had their genome sequenced. Genomic analyses have proposed that there are two major branches of O. oeni strains that might be linked to wine style (sparkling wine versus white and red) and metagenomic studies have suggested a possible influence of terroir. This review explores recent developments of O. oeni including genomic studies examining O. oeni diversity and how this might shape future regional-specific commercial O. oeni starter strains. [ABSTRACT FROM AUTHOR]

Novel sensitive optical biosensor for determination of Grapevine virus A-type (GVA) proteins (GVA-antigens) has been designed. This biosensor was based on thin films of Zinc Oxide (ZnO) deposited by atomic layer deposition (ALD). The ZnO-based films have demonstrated favorable surface-structural properties for the direct immobilization of antibodies against GVA-antigens in order to form a biosensitive layer sensitive to GVA-antigens. The immobilization was confirmed by intensity changes in the main near band emission (NBE) peak of ZnO and by the formation of intense photoluminescence band, discovered in the visible range around 425 nm, caused by the immobilized proteins. The GVA-antigen detection was performed by the evaluation of changes and behavior of a corresponding luminescence band. The sensitivity of as-formed label-free biosensor towards the GVA-antigens was determined in the range from 1 pg/ml to 10 ng/ml; in addition, the selectivity of biosensor was evaluated. [ABSTRACT FROM AUTHOR]

In accordance with Article 6 of Regulation (EC) No 396/2005, the evaluating Member State, Italy, received an application from Syngenta to modify the existing maximum residue level (MRL) for the active substance penconazole in grapes. The data submitted in support of the request are sufficient to derive a MRL proposal of 0.4 mg/kg for the intended use on grapes. Adequate analytical enforcement methods are available to control the residues of penconazole in grapes. Based on the risk assessment results, EFSA concludes that the intended use of penconazole on grapes will not result in a consumer exposure exceeding the toxicological reference values and therefore is unlikely to pose a consumer health risk. However, these results should be considered provisional due to the fact that the risk assessment for triazole derivate metabolites is still pending. [ABSTRACT FROM AUTHOR]

The wine industry is responsible for the production of million tons of waste, such as grape skin, stalk, sludge and seeds, which can be considered inexpensive sources of phenolic compound owing to incomplete extraction during wine production. Phenolic compounds, also called polyphenols, comprise the most abundant bioactive compounds in grape and are recognized by their antioxidant and antimicrobial potential. Because of their functional properties, extracts obtained from grape wastes, which are rich in phenolic compounds, can be employed in the development of many products, ranging from medical to food applications, decreasing the growth of spoilage and pathogenic microorganisms and inhibiting lipid oxidation. These characteristics are motivating the research for alternative sources of natural antioxidant and antimicrobial agents, aimed at decreasing the use of artificial additives, which have been associated with some toxic effects. This article provides a review of the use of grape by-product extracts and their bioactive compounds as natural antioxidant and antimicrobial agents in food products. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Antibacterial effects of unripe grape products (verjuice and sour grape sauce) which are particularly rich in antioxidants and organic acids were evaluated. Survival of Escherichia coli , Listeria monocytogenes, Salmonella Typhimurium and Staphylococcus aureus which were inoculated in unripe grape products at different inoculum doses (2 and 6 log CFU/mL) was determined. All the samples were kept at room temperature (approximately 25 °C) for 0, 5, 15 and 30 min after inoculation with pathogens, separately. The unripe grape products which were inoculated at low inoculum dose inhibited all tested pathogens in 5 min, while it took 15 min for high inoculum dose. The pH, titratable acidity (tartaric acid %) and total sugar content values of the samples were between 2.14–2.74, 2.29–7.10% and 1.19–17.65 g/L, respectively. It was concluded that unripe grape products are microbiologically safe products and they have self-protection systems even when they were contaminated with pathogens at high levels. [ABSTRACT FROM AUTHOR]

Grapes and wine musts harbour a complex microbiome, which plays a crucial role in wine fermentation as it impacts on wine flavour and, consequently, on its final quality and value. Unveiling the microbiome and its dynamics, and understanding the ecological factors that explain such biodiversity, has been a challenge to oenology. In this work, we tackle this using a metagenomics approach to describe the natural microbial communities, both fungal and bacterial microorganisms, associated with spontaneous wine fermentations. For this, the wine microbiome, from six Portuguese wine appellations, was fully characterized as regards to three stages of fermentation – Initial Must (IM), and Start and End of alcoholic fermentation (SF and EF, respectively).The wine fermentation process revealed a higher impact on fungal populations when compared with bacterial communities, and the fermentation evolution clearly caused a loss of the environmental microorganisms. Furthermore, significant differences (p

Grapevine Pinot gris virus (GPGV) is a new virus reported in Europe and several other grape-growing countries. In an attempt to identify a vector for GPGV, samples of the eriophyid mite Colomerus vitis collected from buds and erinea in GPGV-infected vines were analysed by RT-PCR, using specific primers. Molecular analysis revealed the presence of GPGV in C. vitis. Transmission trials were conducted using C. vitis collected from GPGV-infected vines. Mites were able to transmit GPGV to healthy grapevines, suggesting that C. vitis is a potential vector of this virus. [ABSTRACT FROM AUTHOR]

We isolated, identified and characterized yeast strains from grapes, and their fermented musts, sampled in the small island of Linosa, where there are no wineries and therefore the possibility of territory contamination by industrial strains is minimal. By traditional culture-dependent methods, we isolated 3805 colonies, distinguished by molecular methods in 17 different species. Five hundred and forty-four isolates were analysed for the main oenological characteristics such as fermentative vigour with and without sulphites, sugar consumption and production of alcohol, volatile acidity, hydrogen sulphide, glycerol and β-glucosidase. This analysis identified Kluyveromyces marxianus (seldomly used in winemaking) as the most interesting candidate yeast for the production of innovative wines. Significance and Impact of the Study In recent years, interest is growing for wine production by non- Saccharomyces yeasts, both in research and in the industry. This study describes the yeast population of the grapes in a small-secluded island in the Mediterranean Sea, useful site for the search of new strains. Evaluation of fundamental oenological characters identifies potential best yeasts to assay in experimental vinifications. We also describe, for the first time, 14 new colony morphologies on WL Nutrient Agar, culture medium used to monitor the yeast population dynamics. [ABSTRACT FROM AUTHOR]

This study represents the first investigation on ecology of endophytic bacteria isolated from 3 and 15 year-old vine stems of Vitis vinifera cv. Corvina. The analysis was performed by means of culture-dependent techniques. The obtained results showed that new grapevine endophytic genera are being discovered. Moreover, Bacilli and Actinobacteria are frequently isolated from 3 year-old plants, whereas Alpha- and Gamma- Proteobacteria classes are more prevalent in the 15 year-old plants. Shannon–Wiener ( H ) index and analysis of rarefaction curves revealed greater genus richness in young grapevine plants. Furthermore, results evidenced an increase of genotypic group number within specific genera (e.g., Rhizobium and Pantoea ). Among isolated strains from 3 and 15 year-old stems, respectively, 34 and 39% produce siderophores; 22 and 15% secrete ammonia; 22 and 21% produce indole-3-acetic acid; 8.7 and 41% solubilize phosphate. Besides, two strains isolated from 15 year-old grapevines showed 1-aminocyclopropane-1-carboxylate deaminase activity. Antifungal activity analysis evidenced that two Bacillus strains possess growth antagonistic effect toward all the tested fungal strains. Therefore, the present study extends our knowledge of the diversity of the endophytic bacteria by providing new insights into the complexity of the grapevine microbiome. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) is a nephrotoxic mycotoxin which has been found worldwide as a contaminant in wines. It is produced on grapes mainly by molds from Aspergillus section Nigri . This study has demonstrated for the first time the occurrence of black aspergilli on Tannat grapes from Uruguay, in a two year survey. Aspergillus uvarum (uniseriate) and Aspergillus welwitschiae (from Aspergillusniger aggregate) were the prevalent species whereas Aspergillus carbonarius which is considered the main OTA producing species was not detected. OTA production in culture medium was evaluated for native isolates from A. niger aggregate and compared to levels produced by a type strain of A. carbonarius . This work also includes the development of quick and easy molecular methods to identify black aspergilli to species level, avoiding sequencing. [ABSTRACT FROM AUTHOR]

We studied reservatrol biosynthesis in cells of the grape V. amurensis with overexpression of the VaSTS7 gene. The present study demonstrated that overexpression of the VaSTS7 gene increased the resveratrol content in transgenic grape cells by 3.2-6.6 times as compared with control cells. Also, the transformation enhanced dry biomass accumulation; resveratrol production therefore increased significantly, by 4.7-9.7 times, as compared with control cells. [ABSTRACT FROM AUTHOR]

In this work, a SYBR Green I real-time PCR method has been developed for the detection and quantification of Aspergillus carbonarius in grapes by targeting the veA gene with a primer pair (veAF4/veAR4) that specifically amplifies a 91-bp PCR product. The quantification of the fungal DNA was performed by generation of standard curves for two A. carbonarius strains, using spectrophotometrically measured DNA quantities (Log) with a linearity range from 50 to 5 X 10-4 ng of DNA. A high positive correlation (R² > 0.99) between exponential increases of DNA and real-time PCR threshold cycles showed a high amplification efficiency for the assay (E values 100.06 and 101.51%, respectively). Quantification of the fungal genomic DNA in grape samples artificially inoculated with A. carbonarius conidia was successfully performed with a minimum threshold of 104 conidia per g of grape berry. The assay developed would allow reliable, specific, and efficient detection and quantification of A. carbonarius in grapes. [ABSTRACT FROM AUTHOR]

The yeast diversity on wine grapes in Germany, one of the most northern wine growing regions of the world, was investigated by means of a culture dependent approach. All yeast isolates were identified by sequence analysis of the D1/D2 domain of the 26S rDNA and the ITS region. Besides Hanseniaspora uvarum and Metschnikowia pulcherrima , which are well known to be abundant on grapes, Metschnikowia viticola , Rhodosporidium babjevae , and Curvibasidium pallidicorallinum , as well as two potentially new species related to Sporidiobolus pararoseus and Filobasidium floriforme , turned out to be typical members of the grape yeast community. We found M. viticola in about half of the grape samples in high abundance. Our data strongly suggest that M. viticola is one of the most important fermenting yeast species on grapes in the temperate climate of Germany. The frequent occurrence of Cu. pallidicorallinum and strains related to F. floriforme is a new finding. The current investigation provides information on the distribution of recently described yeast species, some of which are known from a very few strains up to now. Interestingly yeasts known for their role in the wine making process, such as Saccharomyces cerevisiae , Saccharomyces bayanus ssp. uvarum , Torulaspora delbrueckii , and Zygosaccharomyces bailii , were not found in the grape samples. [ABSTRACT FROM AUTHOR]

We investigated the potential plant growth-promoting traits of 377 culturable endophytic bacteria, isolated from Vitis vinifera cv. Glera, as good biofertilizer candidates in vineyard management. Endophyte ability in promoting plant growth was assessed in vitro by testing ammonia production, phosphate solubilization, indole-3-acetic acid (IAA) and IAA-like molecule biosynthesis, siderophore and lytic enzyme secretion. Many of the isolates were able to mobilize phosphate (33%), release ammonium (39%), secrete siderophores (38%) and a limited part of them synthetized IAA and IAA-like molecules (5%). Effects of each of the 377 grapevine beneficial bacteria on Arabidopsis thaliana root development were also analyzed to discern plant growth-promoting abilities (PGP) of the different strains, that often exhibit more than one PGP trait. A supervised model-based clustering analysis highlighted six different classes of PGP effects on root architecture. A. thaliana DR5::GUS plantlets, inoculated with IAA-producing endophytes, resulted in altered root growth and enhanced auxin response. Overall, the results indicate that the Glera PGP endospheric culturable microbiome could contribute, by structural root changes, to obtain water and nutrients increasing plant adaptation and survival. From the complete cultivable collection, twelve promising endophytes mainly belonging to the Bacillus but also to Micrococcus and Pantoea genera, were selected for further investigations in the grapevine host plants towards future application in sustainable management of vineyards. [ABSTRACT FROM AUTHOR]

A mechanistic model for Botrytis cinerea on grapevine was developed. The model, which accounts for conidia production on various inoculum sources and for multiple infection pathways, considers two infection periods. During the first period (“inflorescences clearly visible” to “berries groat-sized”), the model calculates: i) infection severity on inflorescences and young clusters caused by conidia (SEV1). During the second period (“majority of berries touching” to “berries ripe for harvest”), the model calculates: ii) infection severity of ripening berries by conidia (SEV2); and iii) severity of berry-to-berry infection caused by mycelium (SEV3). The model was validated in 21 epidemics (vineyard × year combinations) between 2009 and 2014 in Italy and France. A discriminant function analysis (DFA) was used to: i) evaluate the ability of the model to predict mild, intermediate, and severe epidemics; and ii) assess how SEV1, SEV2, and SEV3 contribute to epidemics. The model correctly classified the severity of 17 of 21 epidemics. Results from DFA were also used to calculate the daily probabilities that an ongoing epidemic would be mild, intermediate, or severe. SEV1 was the most influential variable in discriminating between mild and intermediate epidemics, whereas SEV2 and SEV3 were relevant for discriminating between intermediate and severe epidemics. The model represents an improvement of previous B. cinerea models in viticulture and could be useful for making decisions about Botrytis bunch rot control. [ABSTRACT FROM AUTHOR]

Shiraz and Cabernet Sauvignon (Cs) grapevines were grown at near optimal temperatures (25 or 35°C). Gas exchange, fluorescence, metabolic profiling and correlation based network analysis were used to characterize leaf physiology. When grown at 25°C, the growth rate and photosynthesis of both cultivars were similar. At 35°C Shiraz showed increased respiration, non-photochemical quenching and reductions of photosynthesis and growth. In contrast, Cs maintained relatively stable photosynthetic activity and growth regardless of the condition. In both cultivars, growth at 35°C resulted in accumulations of secondary sugars (raffinose, fucose and ribulose) and reduction of primary sugars concentration (glucose, fructose and sucrose), more noticeably in Shiraz than Cs. In spite of similar patterns of metabolic changes in response to growth at 35°C, significant differences in important leaf antioxidants and antioxidant precursors (DHA/ascorbate, quinates, cathechins) characterized the cultivar response. Correlation analysis reinforced Shiraz sensitivity to the 35°C, showing higher number of newly formed edges at 35°C and higher modularity in Shiraz as compared to Cs. The results suggest that the optimal growth temperatures of grapevines are cultivar dependent, and allow a first insight into the variability of the metabolic responses of grapevines under varied temperatures. [ABSTRACT FROM AUTHOR]

The diversity of fungi in grape must and during wine fermentation was investigated in this study by culture-dependent and culture-independent techniques. Carignan and Grenache grapes were harvested from three vineyards in the Priorat region (Spain) in 2012, and nine samples were selected from the grape must after crushing and during wine fermentation. From culture-dependent techniques, 362 isolates were randomly selected and identified by 5.8S-ITS-RFLP and 26S-D1/D2 sequencing. Meanwhile, genomic DNA was extracted directly from the nine samples and analyzed by qPCR, DGGE and massive sequencing. The results indicated that grape must after crushing harbored a high species richness of fungi with Aspergillus tubingensis, Aureobasidium pullulans, or Starmerella bacillaris as the dominant species. As fermentation proceeded, the species richness decreased, and yeasts such as Hanseniaspora uvarum, Starmerella bacillaris and Saccharomyces cerevisiae successively occupied the must samples. The "terroir" characteristics of the fungus population are more related to the location of the vineyard than to grape variety. Sulfur dioxide treatment caused a low effect on yeast diversity by similarity analysis. Because of the existence of large population of fungi on grape berries, massive sequencing was more appropriate to understand the fungal community in grape must after crushing than the other techniques used in this study. Suitable target sequences and databases were necessary for accurate evaluation of the community and the identification of species by the 454 pyrosequencing of amplicons. [ABSTRACT FROM AUTHOR]

Esca is a grapevine trunk disease (GTD) associated with different pathogenic fungi inhabiting the woody tissues. Bacteria can also be found in such tissues and they may interact with these fungal colonizers. Although such types of microbial interactions have been observed for wood diseases in many trees, this has never been studied for grapevine. In this study, the bacterial microflora of different vine status (escasymptomatic and asymptomatic), different anatomical part (trunk and cordon) and different type of tissues (necrotic or not) have been studied. Based on Single Strand Conformation Polymorphism (SSCP) analyses, data showed that (i) specific complexes of bacterial microflora colonize the wood of both necrotic and non-necrotic tissues of esca-foliar symptomatic and asymptomatic vines, and also that (ii) depending on the anatomical part of the plant, cordon or trunk, differences could be observed between the bacterial communities. Such differences were also revealed through the community-level physiological profiling (CLPP) with Biolog EcoplatesTM. Two hundred seventeen bacterial strains were also isolated from plant samples and then assigned to bacterial species based on the 16S rRNA genes. Although Bacillus sp. and Pantoea agglomerans were the two most commonly isolated species from all kinds of tissues, various other taxa were also isolated. Inoculation of vine cuttings with 14 different bacterial species, and one GTD fungus, Neofusicoccum parvum, showed no impact of these bacteria on the size of the wood necroses caused by N. parvum. This study showed, therefore, that bacterial communities differ according to the anatomical part (trunk or cordon) and/or the type of tissue (necrotic or nonnecrotic) of wood of grapevine plants showing external symptoms of esca disease. However, research into bacteria having a role in GTD development needs further studies. [ABSTRACT FROM AUTHOR]

Grapevine trunk fungal pathogens, such as Diplodia seriata and Phaeomoniella chlamydospora, can infect plants through pruning wounds. They cause grapevine trunk diseases and are involved in grapevine decline. Accordingly, the protection of pruning wounds is crucial for the management of grapevine trunk diseases. The efficacy of different natural antifungals in inhibiting the growth of several fungi causing grapevine trunk diseases was evaluated in vitro. The fungi showing greater in vitro efficacy were tested on autoclaved grape wood assays against D. seriata and P. chlamydospora. Based on results from these assays, chitosan oligosaccharide, vanillin, and garlic extract were selected for further evaluation on pruning wounds inoculated with D. seriata and P. chlamydospora in field trials. A significant decrease in plant mortality was observed after 2 years of growth in the plants treated with the different natural antifungals compared to the mortality rate observed in infected plants that were not treated with antifungals. Also, the infection rate for the inoculated pathogens was significantly reduced in plants treated with the selected natural antifungals. Therefore, natural antifungals represent a promising alternative for disease control and could provide significant economic benefits for the grape-growing industry. [ABSTRACT FROM AUTHOR]

The antifungal activity of Nerol (NEL) was evaluated against Aspergillus niger , a known cause of grape spoilage, and possible modes of action were explored. The antifungal efficacy of NEL against A. niger has been proven in a dose-dependent manner through in vitro (mycelial growth and spore germination) and in vivo (grapes) tests. An obvious increase in the membrane permeability was detected through the determination of extracellular pH and conductivity. The damage in the cell membrane was measured by monitoring the influx of Propidium iodide (PI) using flow cytometry and was further verified through the inhibition of ergosterol synthesis in the cell membrane. NEL induced morphological changes, and the integrity of the A. niger fungal cells decreased with increasing NEL concentrations. A dose-dependent decrease in ergosterol production was also seen in A. niger cell membranes upon exposure to NEL. The mechanism-of-action study revealed that NEL activated a membrane-active mechanism that inhibits ergosterol synthesis and consequently compromised the membrane integrity of A. niger . As a result, the membrane permeability changes and causes cell death. The membrane lesion mechanism makes NEL a natural alternative to commercial fungicide for control of stored grape spoilage. [ABSTRACT FROM AUTHOR]

Grapes and wine musts harbor a complex microbiome, which plays a crucial role in wine fermentation as it impacts on wine flavour and, consequently, on its final quality and value. Unveiling the microbiome and its dynamics, and understanding the ecological factors that explain such biodiversity, has been a challenge to oenology. In this work, we tackle this using a metagenomics approach to describe the natural microbial communities, both fungal and bacterial microorganisms, associated with spontaneous wine fermentations. For this, the wine microbiome, from six Portuguese wine appellations, was fully characterized as regards to three stages of fermentation - Initial Musts (IM), and Start and End of alcoholic fermentations (SF and EF, respectively). The wine fermentation process revealed a higher impact on fungal populations when compared with bacterial communities, and the fermentation evolution clearly caused a loss of the environmental microorganisms. Furthermore, significant differences (p < 0.05) were found in the fungal populations between IM, SF, and EF, and in the bacterial population between IM and SF. Fungal communities were characterized by either the presence of environmental microorganisms and phytopathogens in the IM, or yeasts associated with alcoholic fermentations in wine must samples as Saccharomyces and non-Saccharomyces yeasts (as Lachancea, Metschnikowia, Hanseniaspora, Hyphopichia, Sporothrix, Candida, and Schizosaccharomyces). Among bacterial communities, the most abundant family was Enterobacteriaceae; though families of species associated with the production of lactic acid (Lactobacillaceae, Leuconostocaceae) and acetic acid (Acetobacteriaceae) were also detected. Interestingly, a biogeographical correlation for both fungal and bacterial communities was identified between wine appellations at IM suggesting that each wine region contains specific and embedded microbial communities which may contribute to the uniqueness of regional wines. [ABSTRACT FROM AUTHOR]

Aims To provide an efficient technique for monitoring the off-flavoured fungal compound geosmin. Methods and Results Geosmin-associated gpe1 gene of Penicillium expansum displayed ≥99% similarity to cytochrome P450 gene of geosmin-producing P. restrictum, but ≤40% similarities to geosmin biosynthesis, non-cytochromic gene of Streptomyces avermitilis and cytochrome P450 genes of non-geosmin-producing Neotyphodium lolii, Phoma betae and P. paxilli. Serial 10-fold dilutions of P. expansum's DNA was subjected to a previously reported qPCR assay (Atoui et al. 2007), utilizing gpe1 specific primer pair ' SNgpe1F/ SNgpe1R'. A linear relationship between DNA quantity and Cycle Threshold ( Ct), with strong correlative coefficient, was observed. Using the available physico-chemical method, geosmin was quantified in 188 grape samples. Penicillium spp's DNA was quantified in these samples, utilizing the developed qPCR assay. A strong positive correlation ( R2 = 0·97) between Penicillium's DNA and geosmin concentration was observed. Furthermore, <50 ng μl−1 Penicillium's DNA corresponds to geosmin level below the permitted intensity limit i.e. 4, for 'Flavour Profile Analysis'. Conclusions Penicillium spp., genomic DNA level can provide an efficient way to quantify geosmin. Significance and Impact of the Study This particular qPCR technique can be utilized in numerous food industries, for the timely detection and monitoring of geosmin contamination. [ABSTRACT FROM AUTHOR]

In this study, the samples of the spatial soil and organs of the grapevine ( Vitis vinifera) cultivar Tamjanika were collected from the selected zones near the Mining and Smelting Complex Bor (East Serbia). They were analyzed by ICP-OES to determine the content of Cu, Zn, Pb, As, Cd, and Ni with the aim of ascertaining if these data may help in the assessment and improvement of the quality of environment in polluted areas such as Bor and its surrounding area. The results obtained from the calculated biological and enrichment factors, as well as from the Pearson correlation study and hierarchical cluster analysis confirmed that very useful information is recorded in plant organs: root, stem, leaves, and fruit. Yet, when the atmospheric pollution is the sphere of interest, the most informative data are found in unwashed leaves. The results of this study indicated also that the investigated plant species has some highly effective strategies involved in tolerance to the stress induced by heavy metals, which makes it an excellent candidate for phytostabilization purposes. Planting of this grapevine cultivar can be recommended in all areas that are severely polluted with heavy metals. [ABSTRACT FROM AUTHOR]

Aspergillus carbonarius (AC) and Aspergillus ochraceus (AO) are the major ochratoxin A (OTA)-producing fungi isolated from grapes. Seventy-three yeast strains from 10 species were tested for their capabilities in inhibiting the growth and OTA production by AC and AO in agar medium and grape berries using a co-culture method for in vitro and in vivo experiments, respectively. Results showed that five yeast strains, namely, Candida zemplinina M3, Saccharomyces cerevisiae M114 and C297, Pichia kluyveri M117, and Metschnikowia aff. fructicola M179, significantly inhibited AC and AO in agar medium and grape berries. OTA production in grape berries also significantly decreased. The inhibition efficacy varied with the yeast used. Comparatively, M114 showed the highest reduction of decay incidence of 80% and 40% caused by AC and AO, respectively. The spore germination of AC was inhibited when co-cultured with M114 in liquid cultivation but not when co-cultured in yeast-free supernatant. However, the yeast-free supernatant obtained from 3 d of co-culture of AC and M114 inhibited the germination of fungal spores. The population of M114 in grape berries inoculated with AC was higher than that of the control, particularly at 72 h (28.35 times higher). The volatile compounds produced by M114 had no effect on AC growth. In summary, five strains of yeast that can inhibit growth and OTA production by AC and AO were obtained. Results demonstrated the intrinsic mechanism of the inhibition effect, which was possibly attributed to the competition for space and nutrients of fungi and yeasts or the production of antifungal metabolite(s) by yeast in the co-culture. [ABSTRACT FROM AUTHOR]

The aim of study was to detect the microscopic filamentous fungi from wine surface of sterilized grapes berries of Slovak origin. We analyzed 21 samples of grapes, harvested in the year 2012 of various wine-growing regions. For the isolation of species we used the method of direct plating surface-sterilized berries (using 0.4% freshly pre-pared chlorine) on DRBC (Dichloran Rose Bengal Chloramphenicol agar). The cultivation was carried at 25?1?C, for 5 to 7 days. A total number of 2541 fungal isolates pertaining to 18 genera including Mycelia sterilia were recovered. Isolates of genus Alternaria were found in all of tested samples with the highest relative density 56.4%. The second highest isolation frequency we detected for genus Fusarium (90.48% positive samples), but with low relative density (31 isolates and 2.99% RD). Another genera with higher isolation frequency were Cladosporium (Fr 85.71%, RD 14.6%), Mycelia sterilia (Fr 85.71%, RD 4.25%), Penicillium (Fr 80.95%, RD 13.42%), Botrytis (Fr 71.43%, RD 2.95%) Rhizopus (Fr 66.66%, RD 1.34%), Aspergillus (Fr 57.14%, RD 0.87%), Epicoccum (Fr 47.62%, RD 1.22%), Trichoderma (Fr 42.86%, RD 1.26%). Isolation frequency of another eight genera (Arthrinium, Dichotomophtora, Geotrichum, Harzia, Chaetomium, Mucor, Nigrospora and Phoma) was less than 10% and relative density less than 0.5%. Chosen isolates of potential producers of mycotoxin (species of Alternaria, Aspergillus, Fusarium and Penicillium) were tested for the ability to produce relevant mycotoxins in in vitro conditions using TLC method. None isolate of Aspergillus niger aggregate (13 tested) did not produce ochratoxin A - mycotoxin monitored in wine and another products from grapes berries. Isolates of potentially toxigenic species recovered from the samples were found to produce another mycotoxins: aflatoxin B1, altenuene, alternariol, alternariol monomethylether, citrinin, diacetoxyscirpenol, deoxynivalenol, HT-2 patulin, penitrem A and T-2 toxin in in vitro conditions. In conclusion, another research should be performed to detect the occurrence of these mycotoxins in grapes, must, wine and another products from grape. [ABSTRACT FROM AUTHOR]

The diversity of yeasts and bacterial species on grapes has been investigated in vineyards worldwide. For winemaking are very important three groups of microorganisms. First two includes acetic acid and lactic acid bacteria; they live and grow normally on grape surface. The third group includes more than 20 detectable genera of yeasts. There are three principal genera found on grapes Hanseniaspora uvarum (Kloeckera apiculata), Metschnikowia pulcherrima (Candida pulcherrima), and Candida stellata or new descripted Candida zemplinina. Aim of this study was investigate of number of three major groups of microorganisms which are important for grapes and winemaking. The number of bacteria on Acetobacter agar (AA) ranged from 1.76 log CFU/mL to 2.80 log CFU/mL. Lactic acid bacteria were counted on MRS agar and the number of detectable colonies ranged from 0.48 log CFU/mL to 2.06 log CFU/mL. Sabouraud dextrose agar (SDA) was used for cultivation of yeast and the number of yeasts ranged from 2.47 log CFU/mL to 2.76 log CFU/mL. For identification of yeast species were used different types of agar media with acid base indicator bromocresol green. Identified 10 yeasts species includes to genus: Candida, Metschnikowia, Pichia, Kluyveromyces, Hanseniaspora, Hansenula, Candida, Debaromyces, Rhodotorula and Saccharomyces. We identified only few bacterial species includes to genus Lactobacillus, Pediococcus, Gluconobacter and Acetobacter. [ABSTRACT FROM AUTHOR]

The current study investigated an endogenous mycobiota of grapes in Eastern wine region, Slovakia and detection a potentially pathogenic isolates to produce selected mycotoxins. Intact berries from four wine grape cultivars were tested. Seven/eight berries superficially sterilized from each samples were placed on a Dichloran Rose Bengal Chloramphenicol agar in a total of 50 and incubated at 25 ?C, 5 - 7 days. A total of 582 isolates were obtained that belonged to ten genera: Alternaria, Aspergillus, Botrytis, Cladosporium, Epicoccum, Fusarium, Mucor, Penicillium, Rhizopus, Trichoderma and one unidentified genus Mycelium sterillium without creation fruiting bodies. The most frequent were genera Alternaria, Aspergillus, Botrytis and Penicillium with 100% frequention. The most frequent Aspergillus species was Aspergillus section Nigri (100%) and Penicillium species was Penicillium chrysogenum (50%). The largest number of isolates belonged to Alternaria (275 isolates), Cladosporium (114 isolates) and Penicillium (92 isolates). For that reason the relative density of both genera were the highest 42%, 19.6% and 15.8%, respectively. The selected isolates - Aspergillus flavus, Aspergillus section Nigri, Penicillium citrinum, Penicillium expansum and Penicillium chrysogenum were tested for patulin, citrinin, penitrem A, roquefortin C, ochratoxin A, aflatoxin B1, G1 and cyclopiazonic acid producing ability. Out of 11 strains 54% produced at least one mycotoxin. In our research ochratoxigenic microfungi (some species of Aspergillus section Nigri) were found in grape samples but without production of OTA. [ABSTRACT FROM AUTHOR]

Today, occurrence of nanotechnology is making life easier, increasing the individual happiness and attracts attention to the benefits to be provided by it. As with any technology, nanotechnology also has risks, which are discussed here. In this study, toxic effects of ZnOTiO2 nanocomposite on various growth parameters of Drosophila melanogaster and removal of these effects by Cimin grape (Vitis vinifera L. ssp., Cimin) were investigated. For this purpose, assessment of the number of offspring and the survival rate were performed by feeding flies with ZnOTiO2 (1 mg/ml) and Cimin grape seed and fruit extracts (5 and 10 mg/ml). In the first stage, larvae of the the same age were put into the medium of each application group and the adult individuals were recorded. In the second stage, in order to determine the number of offspring in all treatment groups, in a set of experiments the grape extracts and ZnOTiO2 were only applied to the female members, while in another set of experiments, the grape extracts and ZnOTiO2 were applied only to male members, belonging to the same application group. The total number of flies developed from the eggs laid during ten days of pair mating was counted. As a result, survival rate and the offspring number in the application groups, that were only exposed to ZnOTiO2 were found to show a decline, compared with the other groups. At the same time, the values obtained from the groups, exposed to the ZnOTiO2 and grape extracts together, were close to control group values. This result supports the healing effects of Cimin grape, which is abundant in Erzincan. [ABSTRACT FROM AUTHOR]

Plants are constantly under attack from a variety of microorganisms, and rely on a series of complex detection and response systems to protect themselves from infection. Here, we found that a by-product of glutamate fermentation triggered defense responses in grapevine, increasing the expression of defense response genes in cultured cells, foliar chitinase activity, and resistance to infection by downy mildew in leaf explants. To identify the molecule that triggered this innate immunity, we fractionated and purified candidates extracted from Corynebacterium glutamicum, a bacterium used in the production of amino acids by fermentation. Using hydrolysis by lysozyme, a silkworm larva plasma detection system, and gel filtration analysis, we identified peptidoglycan as inducing the defense responses. Peptidoglycans of Escherichia coli, Bacillus subtilis, and Staphylococcus aureus also generated similar defensive responses. [ABSTRACT FROM AUTHOR]

During 2010 and 2012 grape harvest seasons in Cyeonggi-do, Korea, a white stain symptom was observed on the harvested grape fruits in 'Campbell-Early' and 'Kyoho' varieties. In samples collected from the infected vine, two different strains of pathogenic fungi have been found and identified as Acremonium acutatum and Trichothecium roseum based on fungal morphology and nucleotide sequence of internal transcribed spacer (ITS) and supported by the phylogenetic analysis of the rDNA-ITS region. The DNA homologies of the isolated strains were 99.8% and 99.6% identical with T. roseum (IFB-22133) and A. acutatum (CBS682.71), respectively. In the pathogenicity test, the spores of A. acutatum and T. roseum sprayed on the grapes caused white stain symptoms on the fruits in two weeks after the artificial inoculation, which is similar to observations in the field. To our knowledge, this is the first report of white stain symptoms caused by A. acutatum and T. roseum on the grapes in Korea. [ABSTRACT FROM AUTHOR]

Aims: As reliability of preharvest applications of biological control agents (BCAs) to control fruit pathogens is highly dependent on the survival of the selected organism, this study aimed to describe the population dynamics of the yeast-BCA Candida sake (Saito & Ota) CPA-1 on grape berries under the effect of abiotic factors such as temperature, relative humidity, sunlight and rainfall. Methods and Results: Candida sake (5 × 107 CFU ml-1), combined with different concentrations of the food additive Fungicover®, was applied on grape berry clusters. Treated clusters were then exposed to abiotic factors in field or laboratory conditions, recovering populations to describe C. sake population dynamics. The addition of Fungicover significantly increased C. sake multiplication under optimal growth conditions and improved survival under fluctuating abiotic factors. After field applications, significant differences in populations on grape bunches exposed or covered by fine foliage were detected. Simulated rainfall washed off C. sake populations by 0·6-0·9 log units after 20 mm of rain volume. Allowing populations to establish for 24 h or more, prior to a rain event, persistence on grape berries significantly increased and the effect of rain intensity was not observable. Conclusions: Candida sake demonstrated high survival ability under unfavourable environmental conditions and persistence under intense rain. The study evidenced the importance of the first period just after application for C. sake survival on grape tissues and also the protective effect of the additive Fungicover. Significance and Impact of the Study: This research provides new information on the survival of C. sake under field conditions and its practical implications for recommending timing of spray with this antagonist. Our results could be useful for other yeast antagonists applied before harvest. This work, for the first time, defines population dynamics of a yeast BCA using simulated rainfall. [ABSTRACT FROM AUTHOR]

Grape marc used for the production of distilled beverages undergoes prolonged storage which allows alcoholic fermentation to occur. Harsh conditions including low pH, limited oxygen and nutrients, temperature fluctuations, and high ethanol concentrations imposed by that environment create a strong selective pressure on microorganisms. A detailed characterization of the bacterial community during two time points of the fermentation process was performed using high-throughput sequencing of the V3-V6 16S rDNA hypervariable regions. The results revealed a marked reduction in the number of bacterial species after 30 days of incubation and made it possible to identify those species that are able to grow in that extreme environment. The genome sequence of Lactobacillus fabifermentans, one of the dominant species identified, was then analyzed using shotgun sequencing and comparative genomics. The results revealed that it is one of the largest genomes among the Lactobacillus sequenced and is characterized by a large number of genes involved in carbohydrate utilization and in the regulation of gene expression. The genome was shaped through a large number of gene duplication events, while lateral gene transfer contributed to a lesser extent with respect to other Lactobacillus species. According to genomic analysis, its carbohydrate utilization pattern and ability to form biofilm are the main genetic traits linked to the adaptation the species underwent permitting it to grow in fermenting grape marc. [ABSTRACT FROM AUTHOR]

Abstract: Acetic acid bacteria (AAB) diversity from healthy, mould-infected and rot-affected grapes collected from three vineyards of Adelaide Hills (South Australia) was analyzed by molecular typing and identification methods. Nine different AAB species were identified from the 624 isolates recovered: Four species from Gluconobacter genus, two from Asaia and one from Acetobacter were identified by the analysis of 16S rRNA gene and 16S–23S rRNA gene internal transcribed spacer. However, the identification of other isolates that were assigned as Asaia sp. and Ameyamaea chiangmaiensis required more analysis for a correct species classification. The species of Gluconobacter cerinus was the main one identified; while one genotype of Asaia siamensis presented the highest number of isolates. The number of colonies recovered and genotypes identified was strongly affected by the infection status of the grapes; the rot-affected with the highest number. However, the species diversity was similar in all the cases. High AAB diversity was detected with a specific genotype distribution for each vineyard. [Copyright &y& Elsevier]

Abstract: The aim of this study was to evaluate the diversity of black aspergilli isolated from berries from different agroclimatic regions of Spain. Growth characterization (in terms of temperature and water activity requirements) of Aspergillus carbonarius, Aspergillus tubingensis and Aspergillus niger was carried out on synthetic grape medium. A. tubingensis and A. niger showed higher maximum temperatures for growth (>45°C versus 40–42°C), and lower minimum aw requirements (0.83aw versus 0.87aw) than A. carbonarius. No differences in growth boundaries due to their geographical origin were found within A. niger aggregate isolates. Conversely, A. carbonarius isolates from the hotter and drier region grew and produced OTA at lower aw than other isolates. However, little genetic diversity in A. carbonarius was observed for the microsatellites tested and the same sequence of β-tubulin gene was observed; therefore intraspecific variability did not correlate with the geographical origin of the isolates or with their ability to produce OTA. Climatic change prediction points to drier and hotter climatic scenarios where A. tubingensis and A. niger could be even more prevalent over A. carbonarius, since they are better adapted to extreme high temperature and drier conditions. [Copyright &y& Elsevier]

Abstract: Orujo is the name of the Galician (NW of Spain) grape marc distillate. The usual way of Orujo consumption is as young brandy due to the lack of knowledge about the most appropriate type of barrel for aging and the high cost of the final product. However in the past years, demand for this aged distillate has increased. This manuscript has a double aim: contribute to the analytical characterization of this traditional beverage in terms of mineral constituents and evaluate the influence of the species of wooden barrel in the mineral content. Analyses were performed by flame atomic absorption spectrophotometry (Cu, Mn, Zn, Fe, Ca and Mg), flame atomic emission spectrophotometry (Na and K) and inductively coupled plasma mass spectrometry (Al, Cd and Pb). Orujos aged in Quercus alba showed significant higher value for the majority of metals whereas those aged in Quercus petraea showed the lowest contents. K, Na and Ca were the more abundant minerals in the analyzed distillates. The PCA analysis clearly showed a good separation of samples in terms of mineral constituents. The very low concentrations of all minerals evaluated indicated the good manufactured process and the consumer safety of aged Orujos. [Copyright &y& Elsevier]

Aspergillus carbonarius is a major producer of ochratoxin A in grapes, causing fungal decay and posing a significant threat to human health. Bacillus subtilis CCTCC M 207209 was used to inhibit the growth of A. carbonarius CCTCC AF 2011004, an ochratoxin A-producing strain previously isolated from grapes. The inhibition effect in vitro was tested in potato dextrose agar medium (PDA), while in vivo effects were examined in grape berries of three different grape cultivars: Thompson Seedless, Kyoho, and Red Earth. Inhibitory effects were evaluated according to colony size in PDA and rotten spots in grape berries when A. carbonarius and B. subtilis were inoculated simultaneously and cultivated at 0 °C, 25 °C, or 30 °C. B. subtilis liquid cultures with and without cells and volatile products were used in the analyses. Significant inhibition of A. carbonarius was observed in all samples treated with B. subtilis liquid cultures, especially those subjected to cell-free culture treatment. No inhibition was observed for A. carbonarius treated with the volatile products of B. subtilis. The inhibition was the most significant in Red Earth grapes, followed by the Kyoho then Thompson Seedless varieties, when the same fraction of B. subtilis culture was used. Significant inhibition was also observed for other fungal contaminants in grapes when B. subtilis liquid culture supernatant was used. This study reveals the potential of B. subtilis for inhibiting contamination of OTA-producing A. carbonarius and other fungi in table grapes. [ABSTRACT FROM AUTHOR]

Abstract: Aspergillus carbonarius is the main responsible source of ochratoxin A (OTA) in food commodities such as wine, grapes or dried vine fruits from main viticultural regions worldwide. Besides, OTA production is a very consistent property of this species and for this reason atoxigenic isolates of A. carbonarius are very rarely found in natural environments. In the present study, for the first time, three nonochratoxigenic wild strains of A. carbonarius have been discovered, unambiguously identified, characterized in deep and compared to ochratoxigenic strains of the same species. In addition, polyketide synthase (pks) genes suggested to be involved in OTA biosynthesis were also screened in these strains. The identification of the strains was confirmed by ITS-5.8S rRNA, β-tubulin and calmodulin gene sequencing. The three atoxigenic strains did not produce OTA in a conducive culture medium at any of the temperatures and times of incubation tested. Five ketosynthase domains from pks genes previously described in A. carbonarius were detected both in ochratoxigenic and in nonochratoxigenic strains. Atoxigenic strains of A. carbonarius could be useful as biotechnological agents to be used in food industry and as biological agents for control of OTA production in vineyards and other crops. [Copyright &y& Elsevier]

Highlights: [•] Multiplex RT-qPCR. [•] Vitiviruses GVA, GVB and GVD. [•] Comparison between multiplex and singleplex RT-qPCR. [•] Comparison between multiplex RT-PCR and RT-qPCR. [Copyright &y& Elsevier]

Abstract: In this study, attention has been focused on microbial ecology, during an on-vine withering period of 120days, of Mondeuse grapes, an autochthonous variety cultivated in the Western Alps in Europe, and on their fate during alcoholic fermentation. Laboratory fermentations have been followed in order to describe the yeast dynamics in both spontaneous and inoculated fermentations by means of culture-dependent and -independent methods (PCR-DGGE). The ability of Saccharomyces cerevisiae to take over the fermentation has also been assessed by means of minisatellite analysis. The chemical composition has been evaluated on the final products. A biodiversity of the grapes has been detected during the withering period, despite the predominance of Aureobasidium pullulans and Rhodotorula glutinis thus empathising that withering conditions could affect yeast populations. The spontaneous laboratory fermentation was characterized by a predominance of Hanseniaspora uvarum, Metschnikowia fructicola and S. cerevisiae. In the inoculated ones, counts of S. cerevisiae, belonging to the inoculated starter culture, became predominant after 7days, even though the PCR-DGGE analysis showed the starter profile for the entire fermentation period. Finally, when the S. cerevisiae isolates were characterized by the minisatellite analysis, it was determined that the inoculated culture was responsible for the alcoholic fermentation. As far as spontaneous fermentation is concerned, the autochthonous S. cerevisiae showed a good ethanol production yield, but left a high concentration of residual sugars. [Copyright &y& Elsevier]