Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Lett Appl Microbiol ; 76(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37656878

RESUMO

Film-forming yeasts are potential sources of defects in alcoholic beverages. The aim of this study is to assess the growth capacity of Pichia and Candida film-forming yeasts in cider and wine and the effects on their chemical composition. Cider, partially and fully fermented wine were inoculated with strains of C. californica, P. fermentans, P. kluyveri, P. kudriavzevii, P. manshurica, and P. membranifaciens to simulate a post-fermentative contamination. The former three species grew only in cider. Pichia manshurica and P. kudriavzevii displayed high viability in wine up to 13.18% (v v-1) ethanol. Significant changes in odour-active molecules from different chemical groups were observed in cider and wine in the inoculated samples, compared to the non-inoculated ones. Cider is more susceptible to contamination by all of the species tested, due to its low alcohol content, while P. membranifaciens, P. manshurica, and P. kudriavzevii are additionally potential spoilage agents of wine. This study highlights the risk of cider and wine contamination by film-forming yeasts. Their impact on aroma profiles depends on their ability to grow and their metabolism. This study contributes to an understanding of the possible physiological and metabolic mechanisms responsible for film formation and chemical changes in alcoholic beverages.


Assuntos
Vinho , Fermentação , Pichia , Bebidas Alcoólicas , Candida
2.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688769

RESUMO

Pichia and Candida species include biofilm-forming yeasts able to spoil foods and beverages. Strains belonging to 10 Pichia and Candida species isolated from apples, grape musts, and wines were analysed. They were subjected to molecular typing and characterized for their ability to grow and ferment must for cider and wine production, and for their biofilm properties. All strains grew similarly in apple and grape must. Glucose-fermenting strains displayed differentiated fermentation performances. Great variation in SO2 and ethanol sensitivity was observed among the strains. Pichia manshurica strains showed high tolerance to both molecules. Eleven and five surface-spreading biofilm (MAT) phenotypes were identified in solid and liquid media, respectively. Strains produced biofilms with variable thicknesses and widths in culture tubes. Cell adherence and aqueous-hydrocarbon biphasic hydrophobicity assays were carried out. Some Pichia manshurica and P. membranifaciens strains exhibited a high capacity to form a thick biofilm and had high cell adherence and hydrophobicity values. These strains could be more likely to colonize the internal surfaces of tanks. This study evidenced that some Pichia and Candida strains can proliferate during apple and grape must fermentation and may be detrimental the beverage quality, due to their specific biofilm properties.


Assuntos
Malus , Vitis , Vinho , Pichia/metabolismo , Candida/metabolismo , Vitis/metabolismo , Leveduras/metabolismo , Vinho/análise , Fermentação
3.
World J Microbiol Biotechnol ; 39(5): 121, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36929028

RESUMO

This study evaluates the capacity of commercial formulations of synthetic fungicides to inhibit grapevine bacterial growth when sprayed on vineyards to control diseases, such as downy mildew, powdery mildew and secondary rots. Fungicide sensitivity plate assays were carried out on bacteria isolated from vineyards that were also identified and characterized for their plant growth-promoting (PGP) traits and antifungal activity. The high taxonomic variability of bacteria screened with different chemical classes of fungicides is one new finding of this study. Seven out of 11 fungicides were able to inhibit the growth of bacteria at a concentration corresponding to the maximum dose allowed by law in spray treatments of vineyards. Bacterial sensitivity to each fungicide varied greatly. Many sensitive isolates displayed PGP traits and/or antagonistic activity. This study shows the potential impact of fungicidal treatments on grapevine bacterial microbiota. The involvement of bacteria beneficial to the growth and health of plants underlines the importance of this investigation. Our data reveal that the control of a certain disease may be possible using fungicides that have no or low impact on natural non-target microbiota. Understanding the action mechanisms of the active ingredients in these products is a priority for the development of new eco-friendly pesticides.


Assuntos
Fungicidas Industriais , Oomicetos , Vitis , Fungicidas Industriais/farmacologia , Vitis/microbiologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Bactérias
4.
Int J Syst Evol Microbiol ; 69(11): 3385-3391, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31368884

RESUMO

During a survey of yeast populations associated with grape and apple musts used for wine and cider fermentation, respectively, six pink-coloured ballistoconidia-forming yeasts belonging to the order Sporidiobolales (Basidiomycota) were isolated. Phylogenetic analysis inferred using sequences of the internal transcribed spacer (ITS), the D1/D2 domain of the large subunit rRNA gene, the small subunit (SSU) rRNA gene and DNA-directed RNA polymerase II subunit (RPB2) indicated that the six isolates were separated in two novel species. One of the new species, Sporobolomyces agrorum sp. nov., isolated from grape must, had Sporobolomyces roseus and Sporobolomyces metaroseus as its closest relatives, but showed four/two and 16 nucleotide substitutions in the D1/D2 and ITS regions, respectively, to these two species. The other novel species, Sporobolomyces sucorum sp. nov., was found in apple must and was closely related to Sporobolomyces pararoseus and Sporobolomyces patagonicus, but showed two/three and five substitutions in those two regions for its closest relatives. We detected additional representatives of this species, most of them isolated from grapes whose sequences were already available on public databases. A sexual stage could not be observed for the novel species.


Assuntos
Basidiomycota/classificação , Malus/microbiologia , Filogenia , Vitis/microbiologia , Basidiomycota/isolamento & purificação , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Itália , Técnicas de Tipagem Micológica , Análise de Sequência de DNA , Esporos Fúngicos , Leveduras/classificação , Leveduras/isolamento & purificação
5.
Sydowia ; 71: 141-245, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31975743

RESUMO

Thirteen new species are formally described: Cortinarius brunneocarpus from Pakistan, C. lilacinoarmillatus from India, Curvularia khuzestanica on Atriplex lentiformis from Iran, Gloeocantharellus neoechinosporus from China, Laboulbenia bernaliana on species of Apenes, Apristus, and Philophuga (Coleoptera, Carabidae) from Nicaragua and Panama, L. oioveliicola on Oiovelia machadoi (Hemiptera, Veliidae) from Brazil, L. termiticola on Macrotermes subhyalinus (Blattodea, Termitidae) from the DR Congo, Pluteus cutefractus from Slovenia, Rhizoglomus variabile from Peru, Russula phloginea from China, Stagonosporopsis flacciduvarum on Vitis vinifera from Italy, Strobilomyces huangshanensis from China, Uromyces klotzschianus on Rumex dentatus subsp. klotzschianus from Pakistan. The following new records are reported: Alternaria calendulae on Calendula officinalis from India; A. tenuissima on apple and quince fruits from Iran; Candelariella oleaginescens from Turkey; Didymella americana and D. calidophila on Vitis vinifera from Italy; Lasiodiplodia theobromae causing tip blight of Dianella tasmanica 'variegata' from India; Marasmiellus subpruinosus from Madeira, Portugal, new for Macaronesia and Africa; Mycena albidolilacea, M. tenuispinosa, and M. xantholeuca from Russia; Neonectria neomacrospora on Madhuca longifolia from India; Nothophoma quercina on Vitis vinifera from Italy; Plagiosphaera immersa on Urtica dioica from Austria; Rinodina sicula from Turkey; Sphaerosporium lignatile from Wisconsin, USA; and Verrucaria murina from Turkey. Multi-locus analysis of ITS, LSU, rpb1, tef1 sequences revealed that P. immersa, commonly classified within Gnomoniaceae (Diaporthales) or as Sordariomycetes incertae sedis, belongs to Magnaporthaceae (Magnaporthales). Analysis of a six-locus Ascomycota-wide dataset including SSU and LSU sequences of S. lignatile revealed that this species, currently in Ascomycota incertae sedis, belongs to Pyronemataceae (Pezizomycetes, Pezizales).

6.
Mycologia ; 109(3): 495-507, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28849988

RESUMO

A novel species of Botrytis isolated from peony in Alaska, USA, and grape in Trento District, Italy, was identified based on morphology, pathogenicity, and sequence data. The grape and peony isolates share sequence homology in the glyceraldehyde-3-phosphate dehydrogenase (G3PDH), heat shock protein 60 (HSP60), DNA-dependent RNA polymerase subunit II (RPB2), and necrosis- and ethylene-inducing protein 1 and 2 (NEP1 and NEP2) genes that place them in a distinct group closely related to B. aclada, a globally distributed pathogen of onions. Genetic results were corroborated with morphological and pathogenicity trials that included two isolates of B. cinerea and two isolates of B. paeoniae from peony in Alaska and one isolate of B. aclada. The authors observed differences in colony and conidia morphology and ability to cause lesions on different host tissues that suggest that the grape and peony isolates represent a distinct species. Most notably, the grape and peony isolates did not colonize onion bulbs, whereas B. aclada readily produced lesions and prolific sporulation on onion tissue. The new species Botrytis euroamericana is described herein.


Assuntos
Botrytis/classificação , Botrytis/isolamento & purificação , Paeonia/microbiologia , Doenças das Plantas/microbiologia , Vitis/microbiologia , Alaska , Botrytis/genética , Botrytis/crescimento & desenvolvimento , Proteínas Fúngicas/genética , Itália , Técnicas Microbiológicas , Microscopia , Cebolas/microbiologia , Filogenia , Homologia de Sequência
7.
Antonie Van Leeuwenhoek ; 109(2): 197-205, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26581438

RESUMO

A necrotrophic member of the Sclerotiniaceae family (herewith named strain C10) isolated from withered rotten-grapes, is described. Interestingly, the fungus has no defined taxonomic position since it has been impossible to attribute it to an existing genus. Phylogenetic analysis of partial sequences of glyceraldehyde 3-phosphate dehydrogenase (G3PDH), heat shock protein 60 (HSP60) and DNA-directed RNA polymerase II subunit (RPB2), revealed that strain C10 is distantly related to Amphobotrys and Botrytis. This evidence clearly distinguishes this new Sclerotiniaceae member from other taxa of the family. Moreover, its morphological characteristics did not match those of Amphobotrys and Botrytis. Infectivity assays demonstrated that strain C10 could be a potential postharvest pathogen of withered grapes. This study revealed the taxonomic importance of this strain suggesting the existence of a possible new genus, a theory that requires further investigation.


Assuntos
Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Doenças das Plantas/microbiologia , Vitis/microbiologia , Ascomicetos/genética , Proteínas Fúngicas/genética , Dados de Sequência Molecular , Filogenia
8.
Antonie Van Leeuwenhoek ; 108(5): 1171-80, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26459338

RESUMO

Fungi like Cladosporium, Fusarium, Epicoccum and Aureobasidium can occur on withered grapes causing spoilage of passito wine. There is little or no information on the pathogenic role of these fungi. This study describes the isolation, incidence and identification of several isolates from different withered rotten grapes. Representative isolates grouped in several phenotypes were identified by phylogenetic analysis of internal transcribed spacer, actin or elongation factor gene sequences. Isolates of Cladosporium and Fusarium were ascribed to different species, of these C. ramotenellum, C. halotolerans and F. graminearum were isolated from Vitis vinifera for the first time. All Epicoccum and Aureobasidium isolates belonged to E. nigrum and A. pullulans, respectively. Random amplified DNA polymorphism analysis showed high level of heterogenicity among Epicoccum and Fusarium isolates. Infection assays were carried out to evaluate infectivity in some strains under different withering conditions. Fusarium spp. strains had similar infectivity, while significant variability was observed among Cladosporium spp. and E. nigrum strains. A. pullulans resulted particularly infective. This study provided insights into the occurrence and infection of these fungi in fruit-drying rooms with important implications towards control management during the withering.


Assuntos
Ascomicetos/classificação , Cladosporium/classificação , Fusarium/classificação , Vitis/microbiologia , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Cladosporium/genética , Cladosporium/isolamento & purificação , DNA Espaçador Ribossômico , Fusarium/genética , Fusarium/isolamento & purificação , Fenótipo , Filogenia , Doenças das Plantas/microbiologia , Análise de Sequência de DNA
9.
World J Microbiol Biotechnol ; 31(2): 277-93, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25388474

RESUMO

Although the positive role of non-Saccharomyces yeasts on the overall quality of wine is encouraging research into their oenological potential, current knowledge on the topic is still far from satisfactory. This work analyzes the contribution of starter cultures of Torulaspora delbrueckii, inoculated sequentially with Saccharomyces cerevisiae (multi-starter fermentation), on the fermentation and aromas of two different white style wines, i.e., dry and sweet wines. Chemical analysis of Soave and Chardonnay wines (dry wines) showed that multi-starter fermentation greatly affected the content of several important volatile compounds, including 2-phenylethanol, isoamyl acetate, fatty acid esters, C4-C10 fatty acids and vinylphenols. Moreover, strain-specific contributions have been shown by testing two different T. delbrueckii strains. Evidence of the positive impact of T. delbrueckii activity on wine quality was also demonstrated in Vino Santo, a sweet wine. Due to its low production of acetic acid, this non-Saccharomyces yeast is recommended for the fermentation of high sugar grapes. T. delbrueckii also influenced the content of different variety of chemical groups, including lactones. From a sensory perspective, all wines produced by multi-starter fermentation have greater aromatic intensity and complexity than wines resulting from a monoculture fermentation. These results emphasize the potential of employing T. delbrueckii, in association with S. cerevisiae, for the production of white wines of different styles with improved and enhanced flavour.


Assuntos
Saccharomyces cerevisiae/metabolismo , Torulaspora/metabolismo , Vinho/análise , Vinho/microbiologia , Álcoois/análise , Álcoois/química , Técnicas de Cocultura , Fermentação
10.
Food Microbiol ; 42: 142-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24929730

RESUMO

The variation in the coding capacity within Oenococcus oeni can have a significant impact on wine quality. The detection of several genes involved in important metabolic pathways (i.e. citrate, sulphur and arginine metabolisms) was performed on 10 indigenous O. oeni strains from Negroamaro wine, a red table wine (Apulia, Italy). These strains were selected from 95 isolates, collected during spontaneous malolactic fermentation, according to the results of an Amplified Fragment Length Polymorphism (AFLP) analysis. A total of 16 genes were screened, most (11) of which had never previously been assayed on O. oeni. All strains possessed 10 genes encoding enzymes such as malolactic enzyme (mleA), esterase (estA), citrate lyase (citD, citE and citF), citrate transporter (maeP), α-acetolactate decarboxylase (alsD), α- acetolactate synthase (alsS), S-adenosylmethionine synthase (metK) and cystathionine ß-lyase (metC) and resulted negative in the detection of genes encoding cystathionine γ-lyase (metB), ornithine transcarbamylase (arcB) and carbamate kinase (arcC). The sequence of PCR fragments of 11 genes of a representative strain (ITEM 15929) was compared to those of three reference O. oeni strains. The indigenous strain was phylogenetically more similar to PSU-1 and ATCC BAA1163 than AWRI B429. This study describes new genetic markers useful for detecting the genetic potential of O. oeni strains to contribute to aroma production and for investigating the population structure of the species.


Assuntos
Oenococcus/genética , Oenococcus/isolamento & purificação , Vinho/microbiologia , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Itália , Dados de Sequência Molecular , Oenococcus/classificação , Oenococcus/metabolismo , Filogenia
11.
FEMS Yeast Res ; 13(6): 540-52, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23710966

RESUMO

In order to improve the quality of Italian passito wine, produced from withered grapes that can be naturally infected by noble rot, in this study, a novel protocol was developed to select suitable cultures of both Botrytis cinerea to infect grapes (as noble rot) and of Saccharomyces cerevisiae to ferment grapes. A total of 16 B. cinerea isolated from withered grapes were typified by RAPD-PCR, and three representative strains were selected for physiological characterization. The strains showed different mycelial growth and enzymatic activities (i.e. polygalacturonase, protease, and laccase). A total of 15 yeasts were isolated from spontaneous fermented wines, these were identified as S. cerevisiae, and typified at strain level. Seven strains were selected according to RAPD-PCR profiles and tested for their fermentation performances. The effects of B. cinerea and S. cerevisiae cultures on the aroma profile of sweet style wine were preliminary evaluated fermenting artificially botrytized grapes induced with B. cinerea infection. The combination of selected fungi affected the aroma profile of wine according to the variation of the content of important molecules (i.e. alcohols, esters, and lactones). This study has provided valuable information to develop new natural cultures destined to induce grape botrytization and manage fermentation in passito winemaking.


Assuntos
Botrytis/isolamento & purificação , Saccharomyces cerevisiae/isolamento & purificação , Seleção Genética , Vinho/microbiologia , Botrytis/crescimento & desenvolvimento , Botrytis/metabolismo , Botrytis/fisiologia , DNA Fúngico/genética , Enzimas/metabolismo , Fermentação , Itália , Tipagem Molecular , Micélio/crescimento & desenvolvimento , Técnicas de Tipagem Micológica , Técnica de Amplificação ao Acaso de DNA Polimórfico , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiologia
12.
Microorganisms ; 10(4)2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35456845

RESUMO

The characterization of Oenococcus oeni strains isolated from Nero di Troia wine (Apulia, Italy) sampled in two distinct production areas was carried out. The two indigenous populations, consisting of 95 and 97 isolates, displayed high genetic diversity when analyzed by amplified fragments length polymorphisms (AFLP). Based on the UPGMA dendrogram obtained by AFLP analysis, the two populations displayed similar genotypes that grouped in the same clusters with a high level of similarity (>95%). One genotype was found in only one of the two areas. Representative strains of each cluster were analyzed for their enzymatic activities (esterase, ß-glucosidase, and protease), assayed in whole cells, and tested for their metabolic properties (consumption of L-malic acid, citric acid, acetaldehyde, and arginine) and growth parameters. Significant differences among strains, including the reference strain ATCC BAA-1163, were observed for all of these properties. Principal component analysis evidenced phenotypic differences among strains, and well separated some of them belonging to different genotypes. Strains exhibiting the best performances in most of these traits could be further investigated in order to select possible candidates as malolactic starters for Nero di Troia wine. This study provided insights on the population structure of O. oeni of a local winemaking area useful to the understanding of the regional diversity of this bacterium, an issue not yet completely resolved

13.
Microorganisms ; 9(2)2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33498710

RESUMO

An evaluation was conducted of the colonization of Pseudomonas protegens MP12, a plant-growth promoting and antagonistic strain, inoculated in vine plants during a standard process of grapevine nursery propagation. Three in vivo inoculation protocols (endophytic, rhizospheric, and epiphytic) were implemented and monitored by means of both culture-dependent and independent techniques. Endophytic treatment resulted in the colonization of the bacterium inside the vine cuttings, which spread to young leaves during the forcing period. Microscopy analysis performed on transformed dsRed-tagged P. protegens MP12 cells confirmed the bacterium's ability to penetrate the inner part of the roots. However, endophytic MP12 strain was no longer detected once the plant materials had been placed in the vine nursery field. The bacterium also displayed an ability to colonize the rhizosphere and, when the plants were uprooted at the end of the vegetative season, its persistence was confirmed. Epiphytic inoculation, performed by foliar spraying of cell suspension, was effective in controlling artificially-induced Botrytis cinerea infection in detached leaves. The success of rhizospheric and leaf colonization in vine plants suggests potential for the future exploitation of P. protegens MP12 as biofertilizer and biopesticide. Further investigation is required into the stability of the bacterium's colonization of vine plants under real-world conditions in vineyards.

14.
Int J Food Microbiol ; 319: 108505, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-31911210

RESUMO

The bacterial community in the surface of withered grapes, which are partially dehydrated in the post-harvest period to produce Italian passito wine, has been seldom investigated. Fifty epiphytic bacterial strains isolated from withered berries were identified and characterized. Genera such as Bacillus, Brevibacillus, Curtobacterium, Micrococcus, Pseudomonas and Staphylococcus have been identified by comparative sequence and phylogenetic analyses of 16S rRNA gene sequences. Bacillus was predominant and several taxa within this genus have been recognized. All isolates were characterized by PCR fingerprinting and assayed for osmotic tolerance, motility and antifungal activity. Several Bacillus strains displayed antagonistic effects on grape-rotting fungi such as Botrytis cinerea, Penicillium expansum and Aspergillus uvarum. The other strains were weakly or non-antagonistic on these fungi. Assay on antagonistic interactions among bacteria was also carried out. Bacillus strains, which exhibit swimming and swarming motility, have the potential to colonize the grape surface and to compete with their neighbours for space and resources. The occurrence of these isolates could reduce the contamination of fungal pathogens during grape withering. Epiphytic antagonistic bacteria could potentially be of interest for fungal biocontrol in the post-harvest processing of fruit and vegetables.


Assuntos
Antibiose/fisiologia , Bactérias/metabolismo , Fungos/crescimento & desenvolvimento , Vitis/microbiologia , Vinho/microbiologia , Bactérias/genética , Bactérias/isolamento & purificação , Agentes de Controle Biológico , Frutas/microbiologia , Itália , Filogenia , RNA Ribossômico 16S/genética
15.
Electrophoresis ; 30(17): 2988-2995, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19685470

RESUMO

Cultures of Oenococcus oeni, the most important malolactic bacterium, are used to induce malolactic fermentation in wine. Survival assays in two different wines confirmed that cells acclimated for 24 h in half-strength wine-like medium (acclimation medium) enhanced the malolactic performances. To investigate the effect of the pre-incubation phase on cell physiology, a proteomic study was carried out. Total protein extracts of acclimated and non-acclimated cell cultures (control) were analyzed by 2-D-PAGE. A total of 20 out of approximately 400 spots varied significantly. All the spots were identified by MS analysis and most of them were proteins involved in metabolism, transcription/translation processes and stress response. The results revealed the different physiological status between non-acclimated and acclimated cells explaining, in part, their different behavior in wine. Regulation of stress proteins such as heat and cold shock proteins was involved. Moreover, the availability of sugars and amino acids (even if at low concentration) in acclimation medium determined a modulation of energy metabolism enhancing the resistance to stressful conditions (as those that cells find in wine when inoculated). Finally, this proteomic study increased knowledge concerning the physiological changes in freeze-dried culture occurring with pre-inoculation procedures.


Assuntos
Aclimatação/fisiologia , Proteínas de Bactérias/metabolismo , Oenococcus/fisiologia , Proteômica/métodos , Eletroforese em Gel Bidimensional , Fermentação , Liofilização , Espectrometria de Massas , Oenococcus/metabolismo , Estresse Fisiológico/fisiologia , Vinho
16.
Electrophoresis ; 30(6): 957-65, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19229842

RESUMO

The molecular mechanisms involved in tannic-acid (TA)-mediated cell growth retardation and viability prolongation of Lactobacillus plantarum VP08 strain were evaluated by a proteomic analysis of starved cells grown in the presence of TA or glucose as carbon source. The tannase activity and the cell growth retardation as well as viability prolongation were confirmed by enzymatic assay and growing tests, respectively. In order to gain information about the effect triggered at the molecular level by TA, total proteins (extracted from starved cells grown in 250 mg/L TA, or 2 g/L glucose) were analyzed by a 2D-PAGE/MS approach to detect differentially expressed proteins. A total of 15 spots were found to be down-regulated and 21 up-regulated in TA-grown cells. The results indicate an overall impact of TA on proteins involved in some cellular and metabolic pathways: glycolysis, amino acid metabolism, translation and protein folding. The modulation of specific proteins correlates with the positive effect of TA on the survival of tannase-positive L. plantarum.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Lactobacillus plantarum/efeitos dos fármacos , Taninos/farmacologia , Hidrolases de Éster Carboxílico/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Eletroforese em Gel Bidimensional , Perfilação da Expressão Gênica , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Lactobacillus plantarum/enzimologia , Lactobacillus plantarum/crescimento & desenvolvimento , Lactobacillus plantarum/metabolismo , Espectrometria de Massas , Proteômica , Taninos/metabolismo
17.
Int J Food Microbiol ; 289: 223-230, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30391797

RESUMO

Yeast-like fungi and yeasts residing on carposphere of withered grapes for Italian passito wine production have been scarcely investigated. In the present study, isolates from single berries, both sound and damaged, of Nosiola, Corvina and Garganega varieties were analyzed at the end of the withering process. Great variation of cell concentration among single berries was observed. In sound berries, yeast-like fungi were significantly more frequent than yeasts. Species identification of isolates was carried out by BLAST comparative analysis on gene databases and phylogenetic approach. All yeast-like fungi isolates belonged to Aureobasidium pullulans. They displayed different culture and physiological characteristics and inhibitory capacity against phytopathogenic fungi. Moreover, PCR profile analysis revealed high genotypic similarity among these strains. A total of 35 species were recognized among yeast isolates. Ascomycetes prevailed over basidiomycetes. To the best of our knowledge, Naganishia onofrii and Rhodosporidiobolus odoratus were identified for the first time among yeasts isolated from grapes, must or wine. Hanseniaspora uvarum and Starmerella bacillaris were the most frequent species. Most species were found only in one grape variety (nine in Nosiola, 10 in Corvina and five in Garganega). The sanitary state of withered grapes could have an important impact on the structure of these epiphytic populations.


Assuntos
Fungos/fisiologia , Vitis/microbiologia , Leveduras/fisiologia , Biodiversidade , Frutas/microbiologia , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Genes Fúngicos/genética , Genótipo , Itália , Filogenia , Leveduras/classificação , Leveduras/genética , Leveduras/isolamento & purificação
18.
Foods ; 8(12)2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31817273

RESUMO

Experimental passito wines with different percentages of naturally noble-rotten grapes of the Garganega variety were analyzed to evaluate key molecules and odorants related to the typical aroma and sensory profile of botrytized passito wine. Remarkable changes in the concentration of 1-octen-3-ol, 4-terpineol, benzaldehyde, N-(3-methylbutyl)acetamide, and sherry lactone 1 and 2 were observed between sound and noble-rotten wines. Wines were perceived to be different for floral, honey, figs, apricot, and caramel scents. By partial least square regression these descriptors were well correlated to samples. An important positive contribution of sherry lactones, N-(3-methylbutyl)acetamide, vanillin, benzaldehyde, and γ-butyrolactone to honey, apricot, and caramel was observed. It is conceivable that oxidative effects of Botrytis cinerea infection play an important role in the genesis of these chemical and sensory aroma markers. This study provides a predictive tool for winemakers that use natural grape withering to produce wines whose aroma profile is not standardized due to the seasonal variation of noble rot incidence.

19.
Microbiol Res ; 219: 123-131, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30642463

RESUMO

Pseudomonas sp. MP12 was isolated from a soil sample collected in a typical warm-temperate deciduous forest near Brescia, Northern Italy. Phylogenetic analysis identified the species as Pseudomonas protegens. We evidenced in this strain the presence of the genes phlD, pltB and prnC responsible for the synthesis of the antifungal compounds 2,4-diacetylphloroglucinol (2,4-DAPG), pyoluteorin and pyrrolnitrin, respectively. P. protegens MP12 was also shown to produce siderophores and ammonia, yielded positive results with the indole-3-acetic acid test, and was capable of phosphate solubilization. Moreover, P. protegens MP12 exhibited inhibitory effects on in vitro mycelial growth of prominent grapevine (Vitis vinifera) phytopathogens such as Botrytis cinerea, Alternaria alternata, Aspergillus niger, Penicillium expansum and Neofusicoccum parvum. The strain showed activity even against Phaeomoniella chlamydospora and Phaeoacremonium aleophilum, which cause the devastating tracheomycosis/esca disease of grapevine trunks for which no efficacious control methods have been demonstrated so far. Furthermore, the MP12 strain manifested in vivo antifungal activity against B. cinerea on grapevine leaves. Culture-dependent and culture-independent analysis revealed the ability of P. protegens MP12 to efficiently and permanently colonize inner grapevine tissues. These results suggest that P. protegens MP12 could be worth of exploitation as an antifungal biocontrol agent for applications in viticulture.


Assuntos
Antifúngicos/metabolismo , Agentes de Controle Biológico/metabolismo , Fungos/efeitos dos fármacos , Fenóis/metabolismo , Floroglucinol/análogos & derivados , Pseudomonas/metabolismo , Pirróis/metabolismo , Pirrolnitrina/metabolismo , Vitis/microbiologia , Antifúngicos/farmacologia , Agentes de Controle Biológico/farmacologia , Endófitos/metabolismo , Fenóis/farmacologia , Floroglucinol/metabolismo , Floroglucinol/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/terapia , Folhas de Planta/microbiologia , Pseudomonas/isolamento & purificação , Pirróis/farmacologia , Pirrolnitrina/farmacologia , Microbiologia do Solo , Vitis/crescimento & desenvolvimento
20.
Folia Microbiol (Praha) ; 63(6): 677-684, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29736893

RESUMO

Identification of yeasts isolated from apple juices of two cider houses (one located in a plain area and one in an alpine area) was carried out by culture-based method. Wallerstein Laboratory Nutrient Agar was used as medium for isolation and preliminary yeasts identification. A total of 20 species of yeasts belonging to ten different genera were identified using both BLAST algorithm for pairwise sequence comparison and phylogenetic approaches. A wide variety of non-Saccharomyces species was found. Interestingly, Candida railenensis, Candida cylindracea, Hanseniaspora meyeri, Hanseniaspora pseudoguilliermondii, and Metschnikowia sinensis were recovered for the first time in the yeast community of an apple environment. Phylogenetic analysis revealed a better resolution in identifying Metschnikowia and Moesziomyces isolates than comparative analysis using the GenBank or YeastIP gene databases. This study provides important data on yeast microbiota of apple juice and evidenced differences between two geographical cider production areas in terms of species composition.


Assuntos
Biodiversidade , Sucos de Frutas e Vegetais/microbiologia , Malus/microbiologia , Leveduras/isolamento & purificação , Leveduras/metabolismo , Meios de Cultura/metabolismo , Fermentação , Microbiologia de Alimentos , Frutas/metabolismo , Frutas/microbiologia , Malus/metabolismo , Filogenia , Leveduras/classificação , Leveduras/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA