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Virgílio Loureiro - One of the best experts on this subject based on the ideXlab platform.
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New Insights into the Ecological Interaction Between Grape Berry Microorganisms and Drosophila Flies During the Development of Sour Rot
Microbial Ecology, 2012Co-Authors: André Barata, Manuel Malfeito-ferreira, Sara Correia Santos, Virgílio LoureiroAbstract:In this work, we studied the ecological interactions between grape berry microorganisms and Drosophila sp. flies involved in sour rot disease during grape ripening. After veráison the total microbial counts of grape berries affected by sour rot increased from about 2 log CFU/g of berries to more than 7 log CFU/g. Berry damage provoked a clear shift in yeast diversity from basidiomycetes to ascomycetous fermentative species. The latter were mostly Pichia terricola , Hanseniaspora uvarum , Candida zemplinina , and Zygoascus hellenicus . However, these species were not able to produce the metabolites characteristic of sour rot (gluconic and acetic acids) in inoculated berries. On the contrary, the acetic acid bacteria Gluconacetobacter saccharivorans produced high levels of these acids, mainly when berries were incubated in the presence of the insect Drosophila sp. Sour rot was not observed when grape bunches were physically separated from insects, even when berries were artificially injured. The wounds made in berry skin healed in the absence of insects, thus preventing the development of sour rot. Therefore, in the vineyard, the induction of sour rot depends on the contamination of wounded berries by a microbial consortium—yeasts and acetic acid bacteria—transported by drosophilid insects which disseminate sour rot among damaged berries. In the absence of these insects, plant defense mechanisms are effective and lead to skin healing, preventing disease spread. Thus, we showed that Drosophila sp. act as a vector for microorganisms associated with grape sour rot disease.
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Changes in sour rotten grape berry microbiota during ripening and wine fermentation
International journal of food microbiology, 2012Co-Authors: André Barata, Manuel Malfeito-ferreira, Virgílio LoureiroAbstract:This study investigated the microbiota of sour rotten wine grapes and its impact on wine fermentations. Yeasts, lactic acid bacteria (LAB) and acetic acid bacteria (AAB) were enumerated and identified on sound and sour rot grapes during the ripening stage. The alteration of the ecological balance induced by sour rot was particularly evidenced by the unequivocal increase of yeast and AAB counts on rotten grapes, since the beginning of ripening. Yeast and AAB species diversity in rotten grape samples were much higher than those found in sound grapes. LAB populations were low detected from both healthy and sour rotten grapes. The yeast species Issatchenkia occidentalis, Zygoascus hellenicus and Zygosaccharomyces bailii and the AAB species Gluconacetobacter hansenii, Gluconacetobacter intermedius and Acetobacter malorum, were recovered from damaged grapes and resulting grape juices in the winery. Acetobacter orleaniensis and Acetobacter syzygii were only recovered from sour rotten grapes. Dekkera bruxellensis and Oenococcus oeni were only recovered after wine fermentation induced by starter inoculation, irrespective of grape health, probably originating from cellar environment. After malolactic fermentation, racking and sulphur dioxide addition the only remaining species were the yeast Trigonopsis cantarellii and Saccharomyces cerevisiae, independently of the grape health status.
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Sour rot-damaged grapes are sources of wine spoilage yeasts
FEMS yeast research, 2008Co-Authors: André Barata, Amparo Querol, Manuel Malfeito-ferreira, Sara S. González, Virgílio LoureiroAbstract:Yeast species of sound and sour rot-damaged grapes were analysed during fermentation and grape ripening in the vineyard, using general and selective culture media. During 2003 and 2004 vintages, microvinifications were carried out with sound grapes to which different amounts of grapes with sour rot were added. The wine spoilage species Zygosaccharomyces bailii was only recovered during fermentations with sour rot, reaching 5.00 log CFU mL -1 (2003) and 2.48 log CFU mL -1 (2004) at the end of fermentation. The study of yeast populations during the sour rot ripening process (2005 vintage) showed that the veraison-damaged grapes always exhibited higher total yeast counts and a much greater diversity of species. From a total of 22 ascomycetous species, 17 were present only in damaged grapes. The most frequent species were Issatchenkia occidentalis and Zygoascus hellenicus. The spoilage species Z. bailii and Zygosaccharomyces bisporus were consistently isolated exclusively from damaged grapes. This work demonstrates that one of the most dangerous wine spoilage species, Z. bailii, is strongly associated with sour rot grapes and survives during fermentation with Saccharomyces cerevisiae. The use of selective media provides a more accurate characterization of grape contamination species.
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Ascomycetous yeast species recovered from grapes damaged by honeydew and sour rot.
Journal of applied microbiology, 2007Co-Authors: André Barata, Manuel Malfeito-ferreira, F. Seborro, C. Belloch, Virgílio LoureiroAbstract:Aims: To identify ascomycetous yeasts recovered from sound and damaged grapes by the presence of honeydew or sour rot. Methods and Results: In sound grapes, the mean yeast counts ranged from 3AE20 ± 1AE04 log CFU g )1 to 5AE87 ± 0AE64 log CFU g )1 . In honeydew grapes, the mean counts ranged from 3AE88 ± 0AE80 log CFU g )1 to 6AE64 ± 0AE77 log CFU g )1 . In sour rot grapes counts varied between 6AE34 ± 1AE03 and 7AE68 ± 0AE38 log CFU g )1 . Hanseniaspora uvarum was the most frequent species from sound samples. In both types of damage, the most frequent species were Candida vanderwaltii, H. uvarum and Zygoascus hellenicus. The latter species was recovered in high frequency because of the utilization of the selective medium DBDM (Dekkera ⁄Brettanomyces differential medium). The scarce isolation frequency of the wine spoilage species Zygosaccharomyces bailii (in sour rotten grapes) and Zygosaccharomyces bisporus (in honeydew affected grapes) could only be demonstrated by the use of the selective medium ZDM (Zygosaccharomyces differential medium). Conclusions: The isolation of several species only from damaged grapes indicates that damage constituted the main factor determining yeast diversity. The utilization of selective media is required for eliciting the recovery of potentially wine spoilage species. Significance and Impact of the Study: The impact of damaged grapes in the yeast ecology of grapes has been underestimated.
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Evaluation of the inhibitory effect of dimethyl dicarbonate (DMDC) against wine microorganisms.
Food microbiology, 2007Co-Authors: A Costa, André Barata, Manuel Malfeito-ferreira, Virgílio LoureiroAbstract:Several microbial species associated with wine were challenged against increasing concentrations of dimethyl dicarbonate (DMDC). The concentration inducing complete cell death upon addition to red wine was regarded as the minimum inhibitory concentration (MIC). In dry red wines with 12% (v/v) ethanol and pH 3.50, the inactivation depended on the initial cell concentration. For an initial inoculum of 500 CFU/ml, the MIC of the yeasts species Schizosaccharomyces pombe, Dekkera bruxellensis, Saccharomyces cerevisiae and Pichia guilliermondii was 100mg/l. The most sensitive strains belong to Zygosaccharomyces bailii, Zygoascus hellenicus and Lachancea thermotolerans, with MIC of 25mg/l DMDC. For inoculation rates of about 10(6)CFU/ml, the maximum dose of DMDC legally authorized (200mg/l) was not effective against the most resistant species. The addition of 100mg/l potassium metabisulphite (PMB), equivalent to 1mg/l molecular sulphur dioxide, increased the inactivation effect of 100mg/l DMDC over initial yeast populations of 10(6)CFU/ml but did not fully kill S. pombe and S. cerevisiae. Lactic acid and acetic acid bacteria were not killed by the addition of 300 mg/l of DMDC. Trials performed in wines before bottling showed that in most samples indigenous bacterial populations were not affected by 200mg/l DMDC. Therefore, under winery practice, DMDC at the maximum dose legally permitted may be regarded as an efficient preservative to control low contamination rates of yeasts but ineffective against lactic acid and acetic acid bacteria.
Maudy Th Smith - One of the best experts on this subject based on the ideXlab platform.
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Diversity of yeast species from Dutch garden soil and the description of six novel Ascomycetes
Fems Yeast Research, 2018Co-Authors: Marizeth Groenewald, Alejandra Giraldo Lopez, Michel De Vries, Maudy Th Smith, Lorenzo Lombard, Pedro W. CrousAbstract:A Citizen Science initiative by the Westerdijk Fungal Biodiversity Institute and the Utrecht University Museum gave rise to a project where fungal and yeast isolates were obtained and identified from Dutch soil samples. During the current study, 386 yeast strains were isolated from 157 different locations in the Netherlands. These strains were identified using sequence data of the large-subunit rRNA gene (D1/D2 region) and the internal transcribed spacer 1 and 2 regions. A total of 53 different yeast species were found as well as 15 potentially novel species. Six novel ascomycetous species are described during this study that include Hanseniaspora mollemarum sp. nov., Ogataea degrootiae sp. nov., Pichia gijzeniarum sp. nov., Saccharomycopsis oosterbeekiorum sp. nov., Trichomonascus vanleenenius sp. nov. and Zygoascus flipseniorum sp. nov. This study made it possible to incorporate numerous yeast isolates into the CBS collection without any restrictions, which make these isolates readily available for use by others. Many of the isolates represented species of which only a few isolates or even only a single ex-type strain were available. Therefore, it is a clear indication that such biodiversity-orientated Citizen Science projects can enrich the pool of available yeasts for future research projects.
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Zygoascus M.Th. Smith (1986)
The Yeasts, 2011Co-Authors: Vincent Robert, Maudy Th SmithAbstract:This chapter studies the genus Zygoascus. Asexual reproduction is by multilateral budding; pseudohyphae are formed and septate hyphae may also be present. Blastoconidia are formed on pseudohyphae and true hyphae. Hyphal septa have micropores. The species of the genus are homo- or heterothallic. Asci are obovate to spherical and are formed after conjugation between a cell and its bud, between independent cells, or after fusion of hyphal cells. Asci are persistent and contain one to four hemispherical to galeate ascospores. The chapter also discusses physiology/biochemistry and phylogenetic placement of the genus in which sugars are fermented, nitrate assimilation varies among species, and the diazonium blue B reaction is negative, where determined coenzyme Q-9 is the primary ubiquinone. The type species taken is Zygoascus hellenicus. In this chapter the genus Zygoascus is characterized by the production of budding cells, pseudohyphae, septate hyphae, and asci with one to four hemispherical to galeate ascospores, which have a distinct electron-dense base. ?? 2011 Copyright ?? 2011 Elsevier B.V. All rights reserved.
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Taxonomy and phylogeny of the ascomycetous yeast genus Zygoascus, with proposal of Zygoascus meyerae sp. nov. and related anamorphic varieties.
International Journal of Systematic and Evolutionary Microbiology, 2005Co-Authors: Maudy Th Smith, Vincent Robert, G. A. Poot, Wendy Epping, A. W. A. M. De CockAbstract:Physiological characters, mating compatibility, PCR-RAPD fingerprints, mol% G+C content, DNA–DNA relatedness, and large-subunit and internal transcribed spacer rRNA gene sequences of strains assigned to the genus Zygoascus were re-examined. On the basis of those data, and after phylogenetic analyses, an emendation of Zygoascus hellenicus (type material is a cross of CBS 6736T×CBS 5839T) is proposed, comprising two novel anamorphic varieties, Candida steatolytica var. steatolytica (CBS 6736T) and C. steatolytica var. inositophila (CBS 5839T). A novel teleomorphic species, Zygoascus meyerae sp. nov. (type material is a cross of CBS 4099T×CBS 7521T) is described, together with two novel anamorphic varieties corresponding to it, Candida hellenica var. hellenica (CBS 4099T) and C. hellenica var. acidophila (CBS 7115T).
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Fungemia Caused by Zygoascus hellenicus in an Allogeneic Stem Cell Transplant Recipient
Journal of clinical microbiology, 2004Co-Authors: Mary E. Brandt, Carol A. Kauffman, Peter G. Pappas, Naureen Iqbal, Beth A. Arthington-skaggs, Wendy Lee-yang, Maudy Th SmithAbstract:Zygoascus hellenicus (Candida hellenica) was isolated from a blood culture from a patient who had received an allogeneic stem cell transplant. The isolate displayed an antifungal susceptibility pattern of decreased susceptibility to fluconazole and itraconazole, high susceptibility to voriconazole, and low susceptibility to caspofungin. The organism was misidentified by a commercial yeast identification system. This is the first reported case of human infection with this rare ascomycetous yeast.
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CASE REPORTS Fungemia Caused by Zygoascus hellenicus in an Allogeneic Stem Cell Transplant Recipient
2004Co-Authors: Mary E. Brandt, Carol A. Kauffman, Peter G. Pappas, Naureen Iqbal, Beth A. Arthington-skaggs, Wendy Lee-yang, Maudy Th SmithAbstract:Zygoascus hellenicus (Candida hellenica) was isolated from a blood culture from a patient who had received an allogeneic stem cell transplant. The isolate displayed an antifungal susceptibility pattern of decreased susceptibility to fluconazole and itraconazole, high susceptibility to voriconazole, and low susceptibility to caspofungin. The organism was misidentified by a commercial yeast identification system. This is the first reported case of human infection with this rare ascomycetous yeast.
André Barata - One of the best experts on this subject based on the ideXlab platform.
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New Insights into the Ecological Interaction Between Grape Berry Microorganisms and Drosophila Flies During the Development of Sour Rot
Microbial Ecology, 2012Co-Authors: André Barata, Manuel Malfeito-ferreira, Sara Correia Santos, Virgílio LoureiroAbstract:In this work, we studied the ecological interactions between grape berry microorganisms and Drosophila sp. flies involved in sour rot disease during grape ripening. After veráison the total microbial counts of grape berries affected by sour rot increased from about 2 log CFU/g of berries to more than 7 log CFU/g. Berry damage provoked a clear shift in yeast diversity from basidiomycetes to ascomycetous fermentative species. The latter were mostly Pichia terricola , Hanseniaspora uvarum , Candida zemplinina , and Zygoascus hellenicus . However, these species were not able to produce the metabolites characteristic of sour rot (gluconic and acetic acids) in inoculated berries. On the contrary, the acetic acid bacteria Gluconacetobacter saccharivorans produced high levels of these acids, mainly when berries were incubated in the presence of the insect Drosophila sp. Sour rot was not observed when grape bunches were physically separated from insects, even when berries were artificially injured. The wounds made in berry skin healed in the absence of insects, thus preventing the development of sour rot. Therefore, in the vineyard, the induction of sour rot depends on the contamination of wounded berries by a microbial consortium—yeasts and acetic acid bacteria—transported by drosophilid insects which disseminate sour rot among damaged berries. In the absence of these insects, plant defense mechanisms are effective and lead to skin healing, preventing disease spread. Thus, we showed that Drosophila sp. act as a vector for microorganisms associated with grape sour rot disease.
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Changes in sour rotten grape berry microbiota during ripening and wine fermentation
International journal of food microbiology, 2012Co-Authors: André Barata, Manuel Malfeito-ferreira, Virgílio LoureiroAbstract:This study investigated the microbiota of sour rotten wine grapes and its impact on wine fermentations. Yeasts, lactic acid bacteria (LAB) and acetic acid bacteria (AAB) were enumerated and identified on sound and sour rot grapes during the ripening stage. The alteration of the ecological balance induced by sour rot was particularly evidenced by the unequivocal increase of yeast and AAB counts on rotten grapes, since the beginning of ripening. Yeast and AAB species diversity in rotten grape samples were much higher than those found in sound grapes. LAB populations were low detected from both healthy and sour rotten grapes. The yeast species Issatchenkia occidentalis, Zygoascus hellenicus and Zygosaccharomyces bailii and the AAB species Gluconacetobacter hansenii, Gluconacetobacter intermedius and Acetobacter malorum, were recovered from damaged grapes and resulting grape juices in the winery. Acetobacter orleaniensis and Acetobacter syzygii were only recovered from sour rotten grapes. Dekkera bruxellensis and Oenococcus oeni were only recovered after wine fermentation induced by starter inoculation, irrespective of grape health, probably originating from cellar environment. After malolactic fermentation, racking and sulphur dioxide addition the only remaining species were the yeast Trigonopsis cantarellii and Saccharomyces cerevisiae, independently of the grape health status.
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The microbial ecology of wine grape berries.
International journal of food microbiology, 2011Co-Authors: André Barata, M. Malfeito-ferreira, V. LoureiroAbstract: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. This consortium covers yeast species, lactic acid bacteria and acetic acid bacteria. The proportion of these microorganisms depends on the grape ripening stage and on the availability of nutrients. Grape berries are susceptible to fungal parasites until veraison after which the microbiota of truly intact berries is similar to that of plant leaves, which is dominated by basidiomycetous yeasts (e.g. Cryptococcus spp., Rhodotorula spp. Sporobolomyces spp.) and the yeast-like fungus Aureobasidium pullulans. The cuticle of visually intact berries may bear microfissures and softens with ripening, increasing nutrient availability and explaining the possible dominance by the oxidative or weakly fermentative ascomycetous populations (e.g. Candida spp., Hanseniaspora spp., Metschnikowia spp., Pichia spp.) approaching harvest time. When grape skin is clearly damaged, the availability of high sugar concentrations on the berry surface favours the increase of ascomycetes with higher fermentative activity like Pichia spp. and Zygoascus hellenicus, including dangerous wine spoilage yeasts (e.g. Zygosaccharomyces spp., Torulaspora spp.), and of acetic acid bacteria (e.g. Gluconobacter spp., Acetobacter spp.). The sugar fermenting species Saccharomyces cerevisiae is rarely found on unblemished berries, being favoured by grape damage. Lactic acid bacteria are minor partners of grape microbiota and while being the typical agent of malolactic fermentation, Oenococcus oeni has been seldom isolated from grapes in the vineyard. Environmental ubiquitous bacteria of the genus Enterobacter spp., Enterococcus spp., Bacillus spp., Burkholderia spp., Serratia spp., Staphylococcus spp., among others, have been isolated from grapes but do not have the ability to grow in wines. Saprophytic moulds, like Botrytis cinerea, causing grey rot, or Aspergillus spp., possibly producing ochratoxin, are only active in the vineyard, although their metabolites may affect wine quality during grape processing. The impact of damaged grapes in yeast ecology has been underestimated mostly because of inaccurate grape sampling. Injured berries hidden in apparently sound bunches explain the recovery of a higher number of species when whole bunches are picked. Grape health status is the main factor affecting the microbial ecology of grapes, increasing both microbial numbers and species diversity. Therefore, the influence of abiotic (e.g. climate, rain, hail), biotic (e.g. insects, birds, phytopathogenic and saprophytic moulds) and viticultural (e.g. fungicides) factors is dependent on their primary damaging effect.
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Sour rot-damaged grapes are sources of wine spoilage yeasts
FEMS yeast research, 2008Co-Authors: André Barata, Amparo Querol, Manuel Malfeito-ferreira, Sara S. González, Virgílio LoureiroAbstract:Yeast species of sound and sour rot-damaged grapes were analysed during fermentation and grape ripening in the vineyard, using general and selective culture media. During 2003 and 2004 vintages, microvinifications were carried out with sound grapes to which different amounts of grapes with sour rot were added. The wine spoilage species Zygosaccharomyces bailii was only recovered during fermentations with sour rot, reaching 5.00 log CFU mL -1 (2003) and 2.48 log CFU mL -1 (2004) at the end of fermentation. The study of yeast populations during the sour rot ripening process (2005 vintage) showed that the veraison-damaged grapes always exhibited higher total yeast counts and a much greater diversity of species. From a total of 22 ascomycetous species, 17 were present only in damaged grapes. The most frequent species were Issatchenkia occidentalis and Zygoascus hellenicus. The spoilage species Z. bailii and Zygosaccharomyces bisporus were consistently isolated exclusively from damaged grapes. This work demonstrates that one of the most dangerous wine spoilage species, Z. bailii, is strongly associated with sour rot grapes and survives during fermentation with Saccharomyces cerevisiae. The use of selective media provides a more accurate characterization of grape contamination species.
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Ascomycetous yeast species recovered from grapes damaged by honeydew and sour rot.
Journal of applied microbiology, 2007Co-Authors: André Barata, Manuel Malfeito-ferreira, F. Seborro, C. Belloch, Virgílio LoureiroAbstract:Aims: To identify ascomycetous yeasts recovered from sound and damaged grapes by the presence of honeydew or sour rot. Methods and Results: In sound grapes, the mean yeast counts ranged from 3AE20 ± 1AE04 log CFU g )1 to 5AE87 ± 0AE64 log CFU g )1 . In honeydew grapes, the mean counts ranged from 3AE88 ± 0AE80 log CFU g )1 to 6AE64 ± 0AE77 log CFU g )1 . In sour rot grapes counts varied between 6AE34 ± 1AE03 and 7AE68 ± 0AE38 log CFU g )1 . Hanseniaspora uvarum was the most frequent species from sound samples. In both types of damage, the most frequent species were Candida vanderwaltii, H. uvarum and Zygoascus hellenicus. The latter species was recovered in high frequency because of the utilization of the selective medium DBDM (Dekkera ⁄Brettanomyces differential medium). The scarce isolation frequency of the wine spoilage species Zygosaccharomyces bailii (in sour rotten grapes) and Zygosaccharomyces bisporus (in honeydew affected grapes) could only be demonstrated by the use of the selective medium ZDM (Zygosaccharomyces differential medium). Conclusions: The isolation of several species only from damaged grapes indicates that damage constituted the main factor determining yeast diversity. The utilization of selective media is required for eliciting the recovery of potentially wine spoilage species. Significance and Impact of the Study: The impact of damaged grapes in the yeast ecology of grapes has been underestimated.
Manuel Malfeito-ferreira - One of the best experts on this subject based on the ideXlab platform.
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New Insights into the Ecological Interaction Between Grape Berry Microorganisms and Drosophila Flies During the Development of Sour Rot
Microbial Ecology, 2012Co-Authors: André Barata, Manuel Malfeito-ferreira, Sara Correia Santos, Virgílio LoureiroAbstract:In this work, we studied the ecological interactions between grape berry microorganisms and Drosophila sp. flies involved in sour rot disease during grape ripening. After veráison the total microbial counts of grape berries affected by sour rot increased from about 2 log CFU/g of berries to more than 7 log CFU/g. Berry damage provoked a clear shift in yeast diversity from basidiomycetes to ascomycetous fermentative species. The latter were mostly Pichia terricola , Hanseniaspora uvarum , Candida zemplinina , and Zygoascus hellenicus . However, these species were not able to produce the metabolites characteristic of sour rot (gluconic and acetic acids) in inoculated berries. On the contrary, the acetic acid bacteria Gluconacetobacter saccharivorans produced high levels of these acids, mainly when berries were incubated in the presence of the insect Drosophila sp. Sour rot was not observed when grape bunches were physically separated from insects, even when berries were artificially injured. The wounds made in berry skin healed in the absence of insects, thus preventing the development of sour rot. Therefore, in the vineyard, the induction of sour rot depends on the contamination of wounded berries by a microbial consortium—yeasts and acetic acid bacteria—transported by drosophilid insects which disseminate sour rot among damaged berries. In the absence of these insects, plant defense mechanisms are effective and lead to skin healing, preventing disease spread. Thus, we showed that Drosophila sp. act as a vector for microorganisms associated with grape sour rot disease.
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Changes in sour rotten grape berry microbiota during ripening and wine fermentation
International journal of food microbiology, 2012Co-Authors: André Barata, Manuel Malfeito-ferreira, Virgílio LoureiroAbstract:This study investigated the microbiota of sour rotten wine grapes and its impact on wine fermentations. Yeasts, lactic acid bacteria (LAB) and acetic acid bacteria (AAB) were enumerated and identified on sound and sour rot grapes during the ripening stage. The alteration of the ecological balance induced by sour rot was particularly evidenced by the unequivocal increase of yeast and AAB counts on rotten grapes, since the beginning of ripening. Yeast and AAB species diversity in rotten grape samples were much higher than those found in sound grapes. LAB populations were low detected from both healthy and sour rotten grapes. The yeast species Issatchenkia occidentalis, Zygoascus hellenicus and Zygosaccharomyces bailii and the AAB species Gluconacetobacter hansenii, Gluconacetobacter intermedius and Acetobacter malorum, were recovered from damaged grapes and resulting grape juices in the winery. Acetobacter orleaniensis and Acetobacter syzygii were only recovered from sour rotten grapes. Dekkera bruxellensis and Oenococcus oeni were only recovered after wine fermentation induced by starter inoculation, irrespective of grape health, probably originating from cellar environment. After malolactic fermentation, racking and sulphur dioxide addition the only remaining species were the yeast Trigonopsis cantarellii and Saccharomyces cerevisiae, independently of the grape health status.
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Sour rot-damaged grapes are sources of wine spoilage yeasts
FEMS yeast research, 2008Co-Authors: André Barata, Amparo Querol, Manuel Malfeito-ferreira, Sara S. González, Virgílio LoureiroAbstract:Yeast species of sound and sour rot-damaged grapes were analysed during fermentation and grape ripening in the vineyard, using general and selective culture media. During 2003 and 2004 vintages, microvinifications were carried out with sound grapes to which different amounts of grapes with sour rot were added. The wine spoilage species Zygosaccharomyces bailii was only recovered during fermentations with sour rot, reaching 5.00 log CFU mL -1 (2003) and 2.48 log CFU mL -1 (2004) at the end of fermentation. The study of yeast populations during the sour rot ripening process (2005 vintage) showed that the veraison-damaged grapes always exhibited higher total yeast counts and a much greater diversity of species. From a total of 22 ascomycetous species, 17 were present only in damaged grapes. The most frequent species were Issatchenkia occidentalis and Zygoascus hellenicus. The spoilage species Z. bailii and Zygosaccharomyces bisporus were consistently isolated exclusively from damaged grapes. This work demonstrates that one of the most dangerous wine spoilage species, Z. bailii, is strongly associated with sour rot grapes and survives during fermentation with Saccharomyces cerevisiae. The use of selective media provides a more accurate characterization of grape contamination species.
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DOI:10.1111/j.1567-1364.2008.00399.x
2008Co-Authors: Andre ́ Barata, Amparo Querol, Manuel Malfeito-ferreira, Correspondence Andre ́ Barata, Patrizia RomanoAbstract:damaged grapes; sour rot; spoilage yeasts; selective culture media; PCR-RFLP; Zygosaccharomyces spp. Yeast species of sound and sour rot-damaged grapes were analysed during fermentation and grape ripening in the vineyard, using general and selective culture media. During 2003 and 2004 vintages, microvinifications were carried out with sound grapes to which different amounts of grapes with sour rot were added. The wine spoilage species Zygosaccharomyces bailii was only recovered during fermentations with sour rot, reaching 5.00 logCFUmL1 (2003) and 2.48 log CFUmL1 (2004) at the end of fermentation. The study of yeast popula-tions during the sour rot ripening process (2005 vintage) showed that the veraison-damaged grapes always exhibited higher total yeast counts and a much greater diversity of species. From a total of 22 ascomycetous species, 17 were present only in damaged grapes. The most frequent species were Issatchenkia occidentalis and Zygoascus hellenicus. The spoilage species Z. bailii and Zygosaccharomyces bisporus were consistently isolated exclusively from damaged grapes. This work demon-strates that one of the most dangerous wine spoilage species, Z. bailii, is strongly associated with sour rot grapes and survives during fermentation with Sacchar-omyces cerevisiae. The use of selective media provides a more accurate character-ization of grape contamination species
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Ascomycetous yeast species recovered from grapes damaged by honeydew and sour rot.
Journal of applied microbiology, 2007Co-Authors: André Barata, Manuel Malfeito-ferreira, F. Seborro, C. Belloch, Virgílio LoureiroAbstract:Aims: To identify ascomycetous yeasts recovered from sound and damaged grapes by the presence of honeydew or sour rot. Methods and Results: In sound grapes, the mean yeast counts ranged from 3AE20 ± 1AE04 log CFU g )1 to 5AE87 ± 0AE64 log CFU g )1 . In honeydew grapes, the mean counts ranged from 3AE88 ± 0AE80 log CFU g )1 to 6AE64 ± 0AE77 log CFU g )1 . In sour rot grapes counts varied between 6AE34 ± 1AE03 and 7AE68 ± 0AE38 log CFU g )1 . Hanseniaspora uvarum was the most frequent species from sound samples. In both types of damage, the most frequent species were Candida vanderwaltii, H. uvarum and Zygoascus hellenicus. The latter species was recovered in high frequency because of the utilization of the selective medium DBDM (Dekkera ⁄Brettanomyces differential medium). The scarce isolation frequency of the wine spoilage species Zygosaccharomyces bailii (in sour rotten grapes) and Zygosaccharomyces bisporus (in honeydew affected grapes) could only be demonstrated by the use of the selective medium ZDM (Zygosaccharomyces differential medium). Conclusions: The isolation of several species only from damaged grapes indicates that damage constituted the main factor determining yeast diversity. The utilization of selective media is required for eliciting the recovery of potentially wine spoilage species. Significance and Impact of the Study: The impact of damaged grapes in the yeast ecology of grapes has been underestimated.
Jose Manuel Guillamon - One of the best experts on this subject based on the ideXlab platform.
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diversity and evolution of non saccharomyces yeast populations during wine fermentation effect of grape ripeness and cold maceration
Fems Yeast Research, 2006Co-Authors: N Hierro, Angel Gonzalez, Jose Manuel GuillamonAbstract:We have evaluated the effect of grape maturity and cold maceration prior to fermentation on the yeast ecology during wine fermentation. Non-Saccharomyces strains were selectively isolated and identified using two rapid PCR techniques, namely enterobacterial repetitve intergenic consensus-PCR and PCR-intron splice sites, in various wine fermentation conditions. These identifications were further complemented and confirmed by restriction fragment length poymorphism and sequencing analysis of the 5.8S-ITS and D1/D2 ribosomal regions, respectively. Eleven species belonging to five genera were identified. Candida stellata, Hanseniaspora uvarum and Hanseniaspora osmophila were the dominant species, representing almost 90% of the isolates. Minor strains presented different species of the genera Candida, Issatchenkia, Zygoascus and Zygosaccharomyces. Selective isolation made it possible to isolate some species that were hardly related to the wine-making process, such as Issatchenkia hanoiensis, a new species that has only been described recently.
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Diversity and evolution of non‐Saccharomyces yeast populations during wine fermentation: effect of grape ripeness and cold maceration
FEMS yeast research, 2006Co-Authors: N Hierro, Angel Gonzalez, Albert Mas, Jose Manuel GuillamonAbstract:We have evaluated the effect of grape maturity and cold maceration prior to fermentation on the yeast ecology during wine fermentation. Non-Saccharomyces strains were selectively isolated and identified using two rapid PCR techniques, namely enterobacterial repetitve intergenic consensus-PCR and PCR-intron splice sites, in various wine fermentation conditions. These identifications were further complemented and confirmed by restriction fragment length poymorphism and sequencing analysis of the 5.8S-ITS and D1/D2 ribosomal regions, respectively. Eleven species belonging to five genera were identified. Candida stellata, Hanseniaspora uvarum and Hanseniaspora osmophila were the dominant species, representing almost 90% of the isolates. Minor strains presented different species of the genera Candida, Issatchenkia, Zygoascus and Zygosaccharomyces. Selective isolation made it possible to isolate some species that were hardly related to the wine-making process, such as Issatchenkia hanoiensis, a new species that has only been described recently.
