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Biol. Res ; 53: 02, 2020. tab, graf
Article in English | LILACS | ID: biblio-1089077


The budding yeast Saccharomyces cerevisiae has been considered for more than 20 years as a premier model organ- ism for biological sciences, also being the main microorganism used in wide industrial applications, like alcoholic fermentation in the winemaking process. Grape juice is a challenging environment for S. cerevisiae , with nitrogen deficiencies impairing fermentation rate and yeast biomass production, causing stuck or sluggish fermentations, thus generating sizeable economic losses for wine industry. In the present review, we summarize some recent efforts in the search of causative genes that account for yeast adaptation to low nitrogen environments, specially focused in wine fermentation conditions. We start presenting a brief perspective of yeast nitrogen utilization under wine fermentative conditions, highlighting yeast preference for some nitrogen sources above others. Then, we give an outlook of S. cerevisiae genetic diversity studies, paying special attention to efforts in genome sequencing for population structure determination and presenting QTL mapping as a powerful tool for phenotype-genotype correlations. Finally, we do a recapitulation of S. cerevisiae natural diversity related to low nitrogen adaptation, specially showing how different studies have left in evidence the central role of the TORC1 signalling pathway in nitrogen utilization and positioned wild S. cerevisiae strains as a reservoir of beneficial alleles with potential industrial applications (e.g. improvement of industrial yeasts for wine production). More studies focused in disentangling the genetic bases of S. cerevisiae adaptation in wine fermentation will be key to determine the domestication effects over low nitrogen adaptation, as well as to definitely proof that wild S. cerevisiae strains have potential genetic determinants for better adaptation to low nitrogen conditions.

Saccharomyces cerevisiae/metabolism , Wine/microbiology , Adaptation, Physiological , Vitis/metabolism , Fermentation , Nitrogen/metabolism , Saccharomyces cerevisiae/growth & development , Vitis/microbiology
Electron. j. biotechnol ; 38: 10-18, Mar. 2019. tab
Article in English | LILACS | ID: biblio-1051447


Malolactic fermentation (MLF) is a process in winemaking responsible for the conversion of L-malic acid to L-lactic acid and CO2, which reduces the total acidity, improves the biological stability, and modifies the aroma profile of wine. MLF takes place during or after alcoholic fermentation and is carried out by one or more species of lactic acid bacteria (LAB), which are either present in grapes and cellars or inoculated with malolactic starters during the winemaking process. Although the main bacterium among LAB used in commercial starter cultures for MLF has traditionally been Oenococcus oeni, in the last decade, Lactobacillus plantarum has also been reported as a malolactic starter, and many works have shown that this species can survive and even grow under harsh conditions of wine (i.e., high ethanol content and low pH values). Furthermore, it has been proved that some strains of L. plantarum are able to conduct MLF just as efficiently as O. oeni. In addition, L. plantarum exhibits a more diverse enzymatic profile than O. oeni, which could play an important role in the modification of the wine aroma profile. This enzymatic diversity allows obtaining several starter cultures composed of different L. plantarum biotypes, which could result in distinctive wines. In this context, this review focuses on showing the relevance of L. plantarum as a MLF starter culture in winemaking.

Wine/microbiology , Lactobacillus plantarum/metabolism , Fermentation , Malates/metabolism , Vitis/microbiology , Odorants
Braz. j. microbiol ; 47(1): 181-190, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-775120


Abstract In the present work we isolated and identified various indigenous Saccharomyces cerevisiae strains and screened them for the selected oenological properties. These S. cerevisiae strains were isolated from berries and spontaneously fermented musts. The grape berries (Sauvignon blanc and Pinot noir) were grown under the integrated and organic mode of farming in the South Moravia (Czech Republic) wine region. Modern genotyping techniques such as PCR-fingerprinting and interdelta PCR typing were employed to differentiate among indigenous S. cerevisiae strains. This combination of the methods provides a rapid and relatively simple approach for identification of yeast of S. cerevisiae at strain level. In total, 120 isolates were identified and grouped by molecular approaches and 45 of the representative strains were tested for selected important oenological properties including ethanol, sulfur dioxide and osmotic stress tolerance, intensity of flocculation and desirable enzymatic activities. Their ability to produce and utilize acetic/malic acid was examined as well; in addition, H2S production as an undesirable property was screened. The oenological characteristics of indigenous isolates were compared to a commercially available S. cerevisiae BS6 strain, which is commonly used as the starter culture. Finally, some indigenous strains coming from organically treated grape berries were chosen for their promising oenological properties and these strains will be used as the starter culture, because application of a selected indigenous S. cerevisiae strain can enhance the regional character of the wines.

Saccharomyces cerevisiae/classification , Saccharomyces cerevisiae/isolation & purification , Vitis/microbiology , Acetic Acid/metabolism , Bacterial Adhesion , Czech Republic , DNA Fingerprinting , Drug Tolerance , Ethanol/toxicity , Hydrogen Sulfide/metabolism , Molecular Typing , Mycological Typing Techniques , Malates/metabolism , Osmotic Pressure , Polymerase Chain Reaction , Stress, Physiological , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/physiology , Sulfur Dioxide/toxicity
Braz. j. microbiol ; 46(4): 1045-1052, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769662


Abstract High copper (Cu) levels in uprooted old vineyard soils may cause toxicity in transplanted young vines, although such toxicity may be reduced by inoculating plants with arbuscular mycorrhizal fungi (AMF). The objective of this study was to evaluate the effects of AMF on the plant growth, chlorophyll contents, mycorrhizal colonization, and Cu and phosphorus (P) absorption in young vines cultivated in a vineyard soil contaminated by Cu. Commercial vineyard soil with high Cu levels was placed in plastic tubes and transplanted with young vines, which were inoculated with six AMF species (Dentiscutata heterogama, Gigaspora gigantea, Acaulospora morrowiae, A. colombiana, Rhizophagus clarus, R. irregularis) and a control treatment on randomized blocks with 12 replicates. After 130 days, the mycorrhizal colonization, root and shoot dry matter (DM), height increment, P and Cu absorption, and chlorophyll contents were evaluated. The height increment, shoot DM and chlorophyll contents were not promoted by AMF, although the root DM was increased by R. clarus and R. irregularis, which had the greatest mycorrhizal colonization and P uptake. AMF increased Cu absorption but decreased its transport to shoots. Thus, AMF species, particularly R. clarus and R. irregularis, contribute to the establishment of young vines exposed to high Cu levels.

Copper/growth & development , Copper/metabolism , Copper/microbiology , Fungi/growth & development , Fungi/metabolism , Fungi/microbiology , Mycorrhizae/growth & development , Mycorrhizae/metabolism , Mycorrhizae/microbiology , Phosphorus/growth & development , Phosphorus/metabolism , Phosphorus/microbiology , Plant Roots/growth & development , Plant Roots/metabolism , Plant Roots/microbiology , Plant Shoots/growth & development , Plant Shoots/metabolism , Plant Shoots/microbiology , Soil Pollutants/growth & development , Soil Pollutants/metabolism , Soil Pollutants/microbiology , Vitis/growth & development , Vitis/metabolism , Vitis/microbiology
Braz. j. microbiol ; 46(3): 815-823, July-Sept. 2015. tab, ilus
Article in English | LILACS | ID: lil-755801


Pectinolytic enzymes are greatly important in winemaking due to their ability to degrade pectic polymers from grape, contributing to enhance process efficiency and wine quality. This study aimed to analyze the occurrence of pectinolytic yeasts during spontaneous fermentation of Argentine Bonarda grape, to select yeasts that produce extracellular pectinases and to characterize their pectinolytic activity under wine-like conditions. Isolated yeasts were grouped using PCR-DGGE and identified by partial sequencing of 26S rRNA gene. Isolates comprised 7 genera, with Aureobasidium pullulans as the most predominant pectinolytic species, followed by Rhodotorula dairenensis and Cryptococcus saitoi. No pectinolytic activity was detected among ascomycetous yeasts isolated on grapes and during fermentation, suggesting a low occurrence of pectinolytic yeast species in wine fermentation ecosystem. This is the first study reporting R. dairenensis and Cr. saitoi species with pectinolytic activity. R. dairenensis GM-15 produced pectinases that proved to be highly active at grape pH, at 12 °C, and under ethanol and SO2 concentrations usually found in vinifications (pectinase activity around 1.1 U/mL). This strain also produced cellulase activity at 12 °C and pH 3.5, but did not produce β-glucosidase activity under these conditions. The strain showed encouraging enological properties for its potential use in low-temperature winemaking.


Ascomycota/enzymology , Cryptococcus/enzymology , Polygalacturonase/metabolism , Rhodotorula/enzymology , Vitis/microbiology , Wine/microbiology , Argentina , Ascomycota/isolation & purification , Cryptococcus/isolation & purification , Fermentation/physiology , Molecular Sequence Data , Molecular Typing , Mycological Typing Techniques , Polymerase Chain Reaction , Pectins/metabolism , RNA, Ribosomal/genetics , Rhodotorula/isolation & purification
Indian J Exp Biol ; 2015 Feb; 53(2): 109-115
Article in English | IMSEAR | ID: sea-158390


Uncinula necator and Botrytis cinerea are the most destructive pathogens of the grapevine in Tunisia and elsewhere. We used two strains of Bacillus subtilis group, B27 and B29 to control powdery mildew and the grey mold disease of the grapevine. Green house experiments showed that B29 and B27 strains of the bacteria efficiently reduced the severity of powdery mildew up to 50% and 60%, respectively. Further, they decreased Botrytis cinerea development on grape leaf by 77% and 99%, respectively. The mode of action has been shown to be chitinolytic. These two bacteria showed significant production of total proteins discharged into the culture medium. Determination of some chitinolytic enzymes revealed the involvement of N-acetyl glucosaminidase (Nagase), the chitin-1,4-chitobiosidase (Biase) and endochitinase in degrading the mycelium of B. cinerea.

Acetylglucosaminidase/metabolism , Antibiosis/physiology , Ascomycota/chemistry , Ascomycota/physiology , Bacillus subtilis/classification , Bacillus subtilis/enzymology , Bacillus subtilis/physiology , Bacterial Proteins/metabolism , Botrytis/chemistry , Botrytis/physiology , Chitin/metabolism , Chitinases/metabolism , Culture Media, Conditioned/metabolism , Hexosaminidases/metabolism , Host-Pathogen Interactions , Plant Diseases/microbiology , Species Specificity , Time Factors , Vitis/microbiology
Indian J Exp Biol ; 2015 Feb; 53(2): 104-108
Article in English | IMSEAR | ID: sea-158387


We evaluated the effect of addition of commercially available pectolytic enzyme preparations in the must from Sharad variety, cultivated in India and its influence on some oenological parameters of red wine. The small scale fermentations demonstrated marked difference of organoleptic (colour) and rheologic characteristics (filterability, settling rates) and aroma between enzyme treated samples and control samples. We observed 29% enhancement in free-run juice yield and a remarkable 43% reduction in the fermentation time compared to the control. This biotechnological approach has demonstrated the economic feasibility and the benefits of adding 0.05 g. Kg-1 grapes pectolytic enzyme in terms of yield, aroma, colour, clarity and fermentation period.

Beverages/analysis , Beverages/standards , Color , Enzymes/metabolism , Feasibility Studies , Fermentation , Food Technology/methods , Odorants , Pectins/metabolism , Quality Control , Saccharomyces cerevisiae/metabolism , Time Factors , Vitis/metabolism , Vitis/microbiology , Wine/analysis , Wine/standards
Braz. j. microbiol ; 45(2): 411-416, Apr.-June 2014. ilus, graf
Article in English | LILACS | ID: lil-723096


The aims of this work was to characterise indigenous Saccharomyces cerevisiae strains in the naturally fermented juice of grape varieties Cabernet Sauvignon, Grenache, Tempranillo, Sauvignon Blanc and Verdejo used in the São Francisco River Valley, northeastern Brazil. In this study, 155 S. cerevisiae and 60 non-Saccharomyces yeasts were isolated and identified using physiological tests and sequencing of the D1/D2 domains of the large subunit of the rRNA gene. Among the non-Saccharomyces species, Rhodotorula mucilaginosa was the most common species, followed by Pichia kudriavzevii, Candida parapsilosis, Meyerozyma guilliermondii, Wickerhamomyces anomalus, Kloeckera apis, P. manshurica, C. orthopsilosis and C. zemplinina. The population counts of these yeasts ranged among 1.0 to 19 x 10(5) cfu/mL. A total of 155 isolates of S. cerevisiae were compared by mitochondrial DNA restriction analysis, and five molecular mitochondrial DNA restriction profiles were detected. Indigenous strains of S. cerevisiae isolated from grapes of the São Francisco Valley can be further tested as potential starters for wine production.

Biodiversity , Vitis/microbiology , Yeasts/classification , Yeasts/isolation & purification , Brazil , Colony Count, Microbial , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Mycological Typing Techniques , Polymorphism, Restriction Fragment Length , RNA, Ribosomal/genetics , Sequence Analysis, DNA , Yeasts/genetics
Braz. j. microbiol ; 45(1): 59-66, 2014. ilus, tab
Article in English | LILACS | ID: lil-709479


Interactions between yeasts and lactic acid bacteria are strain specific, and their outcome is expected to change in simultaneous alcoholic -malolactic fermentations from the pattern observed in successive fermentations. One Oenococcus oeni strain Lalvin VP41TM was inoculated with two Saccharomyces cerevisiae strains either simultaneously, three days after the yeast inoculation, or when alcoholic fermentation was close to finish. Early bacterial inoculations with each yeast strain allowed for the growth of the bacterial populations, and the length of malolactic fermentation was reduced to six days. Alcoholic fermentation by Lalvin ICV D80® yeast strain left the highest residual sugar, suggesting a negative effect of the bacterial growth and malolactic activity on its performance. In sequential inoculations the bacterial populations did not show actual growth with either yeast strain. In this strategy, both yeast strains finished the alcoholic fermentations, and malolactic fermentations took longer to finish. Lalvin ICV D80® allowed for higher viability and activity of the bacterial strain than Fermicru UY4® under the three inoculation strategies. This was beneficial for the sequential completion of both fermentations, but negatively affected the completion of alcoholic fermentation by Lalvin ICV D80® in the early bacteria additions. Conversely, Fermicru UY4®, which was rather inhibitory towards the bacteria, favored the timely completion of both fermentations simultaneously. As bacteria in early inoculations with low or no SO2 addition can be expected to multiply and interact with fermenting yeasts, not only are the yeast-bacterium strains combination and time point of the inoculation to be considered, but also the amount of bacteria inoculated.

Oenococcus/growth & development , Oenococcus/metabolism , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae/metabolism , Vitis/microbiology , Wine/microbiology , Fermentation
Rev. argent. microbiol ; 44(2): 105-112, jun. 2012. graf, tab
Article in Spanish | LILACS | ID: lil-657620


The aim of this work was to evaluate the potential of grape stalks, an agroindustrial waste, for growth and lignocellulolytic enzyme production via solid-state fermentation, using the following three white rot fungi: Trametes trogii, Stereum hirsutum and Coriolus antarcticus. The decolorization of several dyes by the above mentioned cultures was also investigated. Similar values of dry weight loss of the substrate were measured after 60 days (33-43 %). C. antarcticus produced the highest laccase and Mn-peroxldase activities (33.0 and 1.6 U/g dry solid). The maximum endoglucanase production was measured in S. hirsutum cultures (10.4 U/g), while the endoxylanase peak corresponded to T. trogii (14.6 U/g). The C. antarcticus/grape stalk system seems potentially competitive in bioremediation of textile processing effluents, attaining percentages of decolorization of 93, 86, 82, 82, 77, and 58 % for indigo carmine, malachite green, azure B, remazol brilliant blue R, crystal violet and xylidine, respectively, in 5 h.

El objetivo de este trabajo fue evaluar el potencial del escobajo, un residuo agroindustrial, como sustrato para el crecimiento y la producción de enzimas lignocelulósicas de tres hongos causantes de pudrición blanca en la madera: Trametes trogii, Stereum hirsutum y Coriolus antarcticus. Para ello se utilizaron técnicas de fermentación en estado sólido. También se ensayó la decoloración de colorantes industriales sobre estos cultivos. La pérdida de peso seco del sustrato fue similar después del día 60 (33-43 %). C. antarcticus produjo las mayores actividades de lacasa y Mn-peroxidasa (33,0 y 1,6 U/g peso seco). La mayor actividad endoglucanasa fue medida en cultivos de S. hirsutum (10,4 U/g), y la mayor actividad endoxilanasa en T. trogii (14,6 U/g). El sistema C. antarcticus/escobap mostró un importante potencial para su aplicación en la biorremediación de efluentes textiles, con porcentajes de decoloración de 93, 86, 82, 82, 77 y 58 % para índigo carmín, verde de malaquita, azure B, azul R brillante de remazol, cristal violeta y xilidina, respectivamente, en 5 h.

Biodegradation, Environmental , Basidiomycota/growth & development , Cellulase/isolation & purification , Coloring Agents/metabolism , /isolation & purification , Fungal Proteins/isolation & purification , Industrial Waste , Industrial Microbiology/methods , Laccase/isolation & purification , Lignin/metabolism , Peroxidases/isolation & purification , Plant Stems/microbiology , Vitis/microbiology , Argentina , Basidiomycota/enzymology , Cellulase/metabolism , Coloring Agents/classification , Coriolaceae/enzymology , Coriolaceae/growth & development , /metabolism , Fermentation , Fungal Proteins/metabolism , Laccase/metabolism , Peroxidases/metabolism , Trametes/enzymology , Trametes/growth & development
Rev. argent. microbiol ; 41(3): 177-184, jul.-sep. 2009. graf, tab
Article in English | LILACS | ID: lil-634633


Yeasts belonging to the genus Dekkera/Brettanomyces, especially the species Dekkera bruxellensis, have long been associated with the production of volatile phenols responsible for off-flavour in wines. According to recent reports, the species Pichia guilliermondii could also produce these compounds at the initial stages of fermentation. Based on the abundance of P. guilliermondii in Patagonian winemaking, we decided to study the relevance of indigenous isolates belonging to this species as wine spoilage yeast. Twenty-three indigenous isolates obtained from grape surfaces and red wine musts were analyzed in their capacity to produce volatile phenols on grape must. The relationship between molecular Random Amplified Polymorphic DNA (RAPD) and physiological (killer biotype) patterns detected in indigenous populations of P. guilliermondii and volatile phenol production was also evaluated. Different production levels of 4-ethylphenol, 4-vinylguaiacol and 4-ethylguaiacol were detected among the isolates; however, the values were always lower than those produced by the D. bruxellensis reference strain in the same conditions. High levels of 4-vinylphenol were detected among P. guilliermondii indigenous isolates. The combined use of RAPD and killer biotype allowed us to identify the isolates producing the highest volatile phenol levels.

Las levaduras del género Dekkera/Brettanomyces, sobre todo la especie Dekkera bruxellensis, siempre han sido asociadas con la producción de fenoles volátiles responsables de aromas desagradables en los vinos. Recientemente, se ha demostrado que la especie Pichia guilliermondii también es capaz de producir estos compuestos, particularmente durante las etapas iniciales de la fermentación. Dada la abundancia de P. guilliermondii en las bodegas de la Patagonia, se decidió evaluar la importancia de algunos aislamientos indígenas de esta especie como levaduras alterantes de vinos regionales. Se evaluó la capacidad de producir fenoles volátiles en ensayos sobre mosto de 23 aislamientos de P. guilliermondii provenientes de superficie de uvas y de mostos de fermentación de vinos tintos. Asimismo, se analizó la relación entre los patrones moleculares (RAPD) y fisiológicos (biotipo killer) de estos aislamientos y la producción de fenoles volátiles. Se detectaron diferentes niveles de producción de 4-etilfenol, 4-vinilguayacol y 4-etilguayacol entre los aislamientos de P. guilliermondii analizados; sin embargo, los valores obtenidos fueron en todos los casos inferiores a los producidos por D. bruxellensis cepa de referencia en las mismas condiciones. En general, se detectaron altos niveles de 4-vinilfenol en los mostos fermentados con los aislamientos indígenas de P. guilliermondii. El uso combinado de RAPD-PCR y el biotipo killer permitió identificar los aislamientos que producen los niveles más altos de fenoles volátiles.

Phenols/analysis , Pichia/isolation & purification , Volatile Organic Compounds/analysis , Wine/microbiology , Argentina , Dekkera/metabolism , Fermentation , Guaiacol/analysis , Guaiacol/analogs & derivatives , Killer Factors, Yeast/pharmacology , Mycological Typing Techniques , Polymerase Chain Reaction , Pichia/drug effects , Pichia/genetics , Pichia/metabolism , Random Amplified Polymorphic DNA Technique , Vitis/microbiology , Wine/analysis
Neotrop. entomol ; 36(4): 555-559, July-Aug. 2007. graf, tab
Article in Portuguese | LILACS | ID: lil-464618


O objetivo deste estudo foi registrar e comparar a ocorrência de adultos e imaturos da traça-dos-cachos, Cryptoblabes gnidiella (Millière), em dois vinhedos, nos diferentes estágios fenológicos de Vitis vinifera cv. Pinot Noir, em Bento Gonçalves (29°10'S 51°32'O), RS, no período de 2004-2005. Quinzenalmente a população de imaturos foi monitorada em cachos e ramos de videira, enquanto os adultos, em armadilhas com feromônio sexual sintético. Houve diferença significativa entre o número de indivíduos coletados nos diferentes estágios fenológicos da videira. No período de cachos secos registrou-se o maior número de C. gnidiella. A permanência de cachos secos nos vinhedos após a colheita permite o refúgio dos imaturos de C. gnidiella no período de entressafra.

The aim of this study was to record and compare the occurrence of adults and immature stages of honeydew moth, Cryptoblabes gnidiella (Millière), related with grape phenology in two Pinot Noir (Vitis vinifera) vineyards in Bento Gonçalves (29°10'S 51°32'O), RS, during 2004-2005. Fortnightly, immature stages were monitored in the clusters and grapevine branches, while the adults, in delta traps baited with synthetic sex pheromone. There were significant differences in the number of individuals in different phenologic stages of vineyards. The highest catches of honeydew moth were registered in the period of dry clusters. The permanence of dry cluster after harvest, could serve as refuge for C. gnidiella immatures between seasons.

Lepidoptera/anatomy & histology , Lepidoptera/parasitology , Vitis/immunology , Vitis/microbiology , Vitis
Neotrop. entomol ; 34(2): 355-356, Mar.-Apr. 2005.
Article in Portuguese | LILACS | ID: lil-451416


A cultura da videira é atacada por uma série de pragas que causam prejuízos à produção. Além dos insetos tradicionalmente associados à cultura recentemente foi observada a presença do gorgulho-do-milho Sitophilus zeamais Motschulsky, registrado como praga de grãos armazenados, danificando as bagas próximo à maturação. O dano direto é causado pela perfuração das bagas e o indireto pela proliferação de bactérias que se multiplicam no suco extravasado, concorrendo para o aumento de podridões na pré-colheita. Em parreirais de Vitis vinifera da cultivar Cabernet Sauvignon, em fevereiro de 2003, até 80 por cento das bagas foram danificadas pelo ataque do inseto.

Vineyards are attacked by a series of pests that damage yield. In addition to the insects traditionally associated with the crop, the presence of Sitophilus zeamais Motschulsky, registered as a grain store pest, was observed damaging grapes near maturity. Direct damage is caused by perforation of the grapes and indirect damage from the proliferation of bacteria that multiply in the spilt juice, that lead to increased rot at harvest. In Vitis vinifera grape vines of the Cabernet Sauvignon cultivar, up to 80 percent of the grapes were damaged by insect attack in February 2003.

Coleoptera/classification , Weevils/parasitology , Vitis/microbiology