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1.
J Sci Food Agric ; 100(2): 885-890, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31483055

RESUMO

BACKGROUND: The research focused on the evaluation of the impact of cover cropping on trace metals (Fe, Mn, Cu, Zn, Pb, Co and Cd) and nutrients in vineyard soils and Vitis vinifera L. For this purpose, two types of cover crops (Lolium perenne L. and Medicago sativa L.) and their mixture were planted between vine rows of Muscat white in the vineyard in South Crimea. Trace elements, nutrients and other parameters were analyzed in the soil layers, leaves and grapevines of control and cover cropped plots. RESULTS: The effect of cover cropping was dependent on applied plant species. Ryegrass (L. perenne L.) seems to compete with V. vinifera L. for nutrients - these were lower in the soil and vines of the treated plot. In parallel, lead (Pb) bioconcentration in grapevines was reduced. In contrast, under lucerne (M. sativa L.), nitrogen in the soil and vines, and trace metal bioconcentration (Fe, Pb and Co) were higher. CONCLUSIONS: Our results indicate that cover cropping can influence the chemical composition of soil and vines. This should be considered when selecting cover crops. © 2019 Society of Chemical Industry.


Assuntos
Produção Agrícola/métodos , Lolium/crescimento & desenvolvimento , Medicago/crescimento & desenvolvimento , Oligoelementos/análise , Vitis/química , Frutas/química , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Lolium/metabolismo , Medicago/metabolismo , Nutrientes/análise , Nutrientes/metabolismo , Solo/química , Especificidade da Espécie , Oligoelementos/metabolismo , Vitis/crescimento & desenvolvimento , Vitis/metabolismo
2.
Food Chem ; 305: 125502, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606692

RESUMO

Melatonin, a tryptophan derivative, is an important functional component in grape berries. We investigated the effect of cluster bagging on melatonin biosynthesis in the berries of two wine grape cultivars, Cabernet Sauvignon and Carignan, during fruit development and ripening. Cluster bagging delayed fruit coloring and ripening, and bag-treated berries of both grape cultivars synthesized more melatonin and most of the precursor compounds including L-tryptophan, N-acetylserotonin, tryptamine, and serotonin compared to those exposed to light (control) conditions. Interestingly, 5-methoxytryptamine was only detected in the berries of Carignan and not of Cabernet Sauvignon, both in the cluster bagging and control groups. In addition, melatonin and most of its precursors, decreased after veraison. VvSNAT1 and VvT5H expression levels were positively correlated with melatonin content. Our findings suggested that melatonin synthesis pathways differ among grape cultivars, and that VvSNAT1 and VvT5H may show key regulatory roles in the melatonin synthesis of grape berries.


Assuntos
Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Melatonina/biossíntese , Vitis/crescimento & desenvolvimento , Vitis/metabolismo , Vinho
3.
Food Chem ; 305: 125484, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514048

RESUMO

Grape pathogenesis-related proteins can cause haze in wine that is undesirable for consumers. Bentonite is used to remove these proteins but is a non-renewable natural material and reduces wine volume due to poor settling. As a potential bentonite alternative, grape seeds powder (GSP) was added to four wines and two grape juice varieties. Addition to wine required high doses (25-32 g/L) for protein removal and haze prevention and this induced changes to wine composition. By contrast, addition to grape juice prior to fermentation required substantially lower doses of GSP (5 g/L) to prevent haze formation. Further 20 g/L of GSP added to the must induced less changes to wine composition than direct addition of GSP to the wine. No changes were recorded in the efficacy of protein removal by changing the GSP source (red or white grape marc), or by using grape seed roasting. Despite the need for additional trials, these preliminary results suggest that GSP may be considered as a viable alternative to bentonite especially when added to juice prior to fermentation.


Assuntos
Pós/química , Vitis/química , Adsorção , Bentonita/química , Cor , Estudos de Viabilidade , Qualidade dos Alimentos , Sucos de Frutas e Vegetais/análise , Proteínas de Plantas/química , Sementes/química , Sementes/metabolismo , Vitis/metabolismo , Vinho/análise
4.
Food Chem ; 307: 125518, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31644976

RESUMO

The Greek vineyard is home to many minor, indigenous grape cultivar whose diverse polyphenolic content has remained largely unexploited. The study aimed at assaying and assessing the polyphenolic content and antioxidant capacity of: (a) five obscure cultivars; (b) Six biotypes of cultivar 'Liatiko'; (c) Five prominent cultivars; and (d) three French varieties included for comparison reasons. Results revealed all samples exhibiting high polyphenol content and antioxidant capacity levels. 'Vertzami' recorded the highest concentrations in berry skins total anthocyanins, flavanols, flavonols, antioxidant capacity. 'Mandilaria' scored the highest value in seed total flavanols compared to all biotypes and cultivars. All 'Liatiko' biotypes scored the highest concentrations in seed total flavonoids and flavonols. 'Liatiko' and its biotypes exhibited different polyphenolic profiles between them. Owing to the climate change, those indigenous varieties' substantial polyphenol amounts, and the differences between biotypes, will allow viticulturists to select the varieties/biotypes most appropriate for obtaining higher quality products.


Assuntos
Antioxidantes/química , Polifenóis/química , Vitis/química , Antocianinas/análise , Mudança Climática , Flavonoides/análise , Flavonóis/análise , Frutas/química , Frutas/metabolismo , Grécia , Polifenóis/análise , Sementes/química , Sementes/metabolismo , Vitis/metabolismo
5.
Int J Food Microbiol ; 312: 108373, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31654841

RESUMO

The use of non-Saccharomyces yeast in conjunction with Saccharomyces cerevisiae in wine fermentation is a growing trend in the wine industry. Non-Saccharomyces, through their distinctive production of secondary metabolites, have the potential to positively contribute to wine sensory profile. To discover new candidate strains for development as starter cultures, indigenous non-Saccharomyces were isolated from un-inoculated fermenting Shiraz musts from a South Australian vineyard (McLaren Vale wine region) and characterised. Among the 77 isolates, 7 species belonging to 5 genera (Kazachstania, Aureobasidium, Meyerozyma, Wickerhamomyces and Torulaspora) were identified by sequencing the internal transcribed spacer regions of the 5.8S rRNA gene (ITS1-5.8S-ITS2 region). The indigenous isolates were evaluated for oenological properties, namely, ethanol tolerance, enzyme activity, and H2S production. To determine their potential industrial use as starter cultures, representative isolates of each species were assessed in a sterile chemically defined grape juice and Viognier grape juice to evaluate their contribution to fermentation kinetics and production of key metabolites, including volatile compounds.


Assuntos
Saccharomycetales/genética , Saccharomycetales/metabolismo , Vitis/metabolismo , Vinho/microbiologia , Leveduras/metabolismo , Austrália , DNA Intergênico/genética , Fazendas , Fermentação , RNA Ribossômico 5,8S/genética , Saccharomycetales/classificação , Saccharomycetales/isolamento & purificação , Austrália do Sul , Vinho/análise
6.
Int J Food Microbiol ; 312: 108362, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31669764

RESUMO

Stuck and sluggish fermentations are among the main problems in winemaking industry leading to important economic losses. Several factors have been described as causes of stuck and sluggish fermentations, being exposure to extreme temperatures barely studied. The objective of this study was to identify thermal conditions leading to stuck and sluggish fermentations, focusing on the impact of an abrupt and transient decrease/increase of temperature on fermentation performance and yeast viability/vitality. Different strains of Saccharomyces cerevisiae, SBB11, T73, and PDM were evaluated in synthetic grape must fermentations. Cold shocks (9 °C and 1.5 °C for 16 h) carried out on different days during the fermentation process were unable to alter fermentation performance. Conversely, shock temperatures higher than 32 °C, applied in early stages of the process, lead to sluggish fermentation showing a delay directly related to the temperature increase. Fermentation delay was associated with a decrease in cell vitality. The impact of the heat shock on fermentation performance was different depending on the strain evaluated and nitrogen supplementation (with or without diammonium phosphate addition). None of the conditions evaluated produced a stuck fermentation and importantly, in all cases must nutrition improved fermentation performance after a heat shock.


Assuntos
Temperatura Baixa , Fermentação/fisiologia , Temperatura Alta , Saccharomyces cerevisiae/metabolismo , Resposta ao Choque Frio/fisiologia , Resposta ao Choque Térmico/fisiologia , Fosfatos/farmacologia , Vitis/metabolismo , Vinho/análise
7.
J Sci Food Agric ; 100(2): 825-835, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31646642

RESUMO

BACKGROUND: Seaweeds are defined as novel elicitors in many crops, allowing the synthesis of secondary metabolites to be triggered in different plant tissues. Currently, the phenolic composition of Tempranillo Blanco grapes and wines is unreported. The present study aimed to investigate the effects of an Ascophyllum nodosum seaweed extract applied to Tempranillo Blanco grapevines, at low (Ld) and high (Hd) dosages, on grape and wine phenolic compounds during two consecutive seasons (2017-2018). RESULTS: The results obtained showed that catechin was the most abundant phenolic compound in Tempranillo Blanco grapes and wines. Season affected the weight of 100 berries and some enological parameters. Catechin and flavonols concentrations in grapes were increased after Hd application to grapevines, independently of season. The concentration of hydroxycinnamic and hydroxybenzoic acids in wines was affected by vintage, probably as a result of oxidation reactions, as well as pinking phenomena, whereas the stilbenes content in wines was conditioned by the affect of cryptogamic diseases in grapes. CONCLUSION: Seaweeds might act as an elicitor of several phenolic compounds in grapes, enhancing the content of some phenolic compounds in wines. © 2019 Society of Chemical Industry.


Assuntos
Feófitas/química , Fenóis/química , Extratos Vegetais/farmacologia , Alga Marinha/química , Vitis/química , Cromatografia Líquida de Alta Pressão , Fertilizantes/análise , Flavonóis/análise , Flavonóis/metabolismo , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Fenóis/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Estilbenos/análise , Estilbenos/metabolismo , Vitis/efeitos dos fármacos , Vitis/metabolismo , Vinho/análise
8.
J Agric Food Chem ; 67(51): 14137-14142, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31802665

RESUMO

Smoke-taint is a wine defect that may occur when ripening grape crops absorb volatile phenols (VPs), compounds associated with the negative sensory attributes of smoke-taint, due to exposure of grapes to wildfire smoke. This study examined potential methods to reduce the impact that smoke-exposure has on wine grapes. Specifically, agricultural sprays normally used to protect grapes from fungal pathogens and a spray used to prevent cracking in soft-fleshed fruits were assessed for their capacity to inhibit increases in VP concentrations in wine grapes following on-vine smoke-exposure. The results indicated that an artificial grape cuticle applied 1 week before exposure to simulated forest fire smoke (at 1-2 weeks after veraison) can significantly hinder an increase in VP concentrations in smoke-exposed grapes at commercial maturity. This reduction in VP concentrations may mitigate crop losses experienced globally by the wine industry due to exposure of grapes on-vine (at key phenological stages) to wildfire smoke.


Assuntos
Produção Agrícola/métodos , Frutas/efeitos dos fármacos , Fumaça/efeitos adversos , Vitis/crescimento & desenvolvimento , Vinho/análise , Frutas/química , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Fenóis/metabolismo , Fumaça/análise , Vitis/química , Vitis/efeitos dos fármacos , Vitis/metabolismo , Incêndios Florestais
9.
Cell Biochem Biophys ; 77(4): 367-377, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31659617

RESUMO

Cisplatin is a widely used anti-cancer drug. However, cisplatin is limited in clinical treatment because of its severe nephrotoxicity. This study reported whether O-GSP can antagonize the cisplatin-induced cytotoxicity in HEK293 cells through inducing HO-1 protein expression. We previously demonstrated O-GSP can increase the survival rate of HEK293 and have protective effect on HEK293 cells. Herein, We found that O-GSP can antagonize cisplatin nephrotoxicity through regulating the expression of HO-1. O-GSP promotes the translocation of Nrf2 in the nucleus, and activates the ERKN JNK pathway and p38 MAPK pathway. Interestingly, p38 MAPK plays a major role in HO-1 expression induced by O-GSP. And O-GSP can modulate the decrease of Nrf2 and HO-1 expression induced by cisplatin, and improve the cisplatin-induced activity and apoptosis rate of cells by stimulating the expression of HO-1. However, the protective effects of O-GSP are inhibited by ZnPP IX. Collectively, the results indicated that O-GSP induced the expression of HO-1 through p38MAPK and Nrf2 pathway in HEK293 cells.


Assuntos
Antineoplásicos/farmacologia , Biflavonoides/farmacologia , Catequina/farmacologia , Cisplatino/farmacologia , Heme Oxigenase-1/metabolismo , Proantocianidinas/farmacologia , Regulação para Cima/efeitos dos fármacos , Vitis/química , Apoptose/efeitos dos fármacos , Núcleo Celular/metabolismo , Células HEK293 , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Sementes/química , Sementes/metabolismo , Transdução de Sinais/efeitos dos fármacos , Vitis/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
BMC Plant Biol ; 19(1): 404, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31521112

RESUMO

BACKGROUND: To limit the impact of the downy mildew disease of grapevine and reduce the need to recur to chemical treatments, an effective strategy might be recovering adaptive resistance traits in both cultivated and wild V. vinifera germplasm. Considering that stilbenes represent the most important class of phytoalexins in the Vitaceae, the constitutive expression and transcriptional activation of all the functional members of the stilbene synthase gene family were analysed in a group of nine grapevine genotypes following artificial infection with the oomycete Plasmopara viticola, the causal agent of the disease. In addition, in the same genotypes we analyzed the expression of genes encoding for two transcription factors involved in the transcriptional regulation of the stilbene synthase genes, namely VvMYB14 and VvMYB15, and of genes encoding for chalcone synthases. RESULTS: Downy mildew incidence and severity ranged from nihil to high in the grapevine genotypes considered, being low to moderate in a subgroup of V. vinifera genotypes. The constitutive expression of the stilbene synthase genes as well as the extent of their transcriptional activation following P. viticola inoculation appeared to be inversely related to the proneness to develop disease symptoms upon infection. In a specular manner, following P. viticola inoculation all the chalcone synthase genes were up-regulated in the susceptible grapevine genotypes and down-regulated in the resistant ones. The infection brought by P. viticola appeared to elicit a co-ordinated and sequential transcriptional activation of distinct stilbene synthase genes subsets, each of which may be regulated by a distinct and specific MYB transcription factor. CONCLUSIONS: The present results suggest that the induction of stilbene biosynthesis may contribute to the basal immunity against the downy mildew of grapevine, thus representing an adaptive resistance trait to recover, in both cultivated and wild V. vinifera germplasm. During the early stages of P. viticola infection, an antagonistic interaction between flavonol and stilbene biosynthesis might occur, whose outcome might determine the subsequent extent of disease symptoms. Further studies are needed to decipher the possible regulatory mechanisms involved in the antagonistic crosstalk between these two metabolic pathways in resistant and susceptible genotypes in response to P. viticola.


Assuntos
Aciltransferases/genética , Oomicetos/patogenicidade , Doenças das Plantas/microbiologia , Vitis/enzimologia , Vitis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Genótipo , Doenças das Plantas/genética
11.
J Agric Food Chem ; 67(39): 10913-10920, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31532663

RESUMO

Copper in grape musts can influence the fermentation efficiency of Saccharomyces cerevisiae during winemaking. The present study revealed the impact of glutathione addition on yeast strains with variable copper sensitivity. The antioxidant glutathione increased yeast vitality and fastened sugar metabolism at copper concentrations up to 0.39 mM. A significant accumulation of acetaldehyde at high copper concentrations was mitigated by the addition of 20 mg L-1 glutathione. Low recovery of glutathione added implicated a complexation of both compounds. Specific alcohol dehydrogenase (ADH) activity was inhibited or reduced in the enzyme extracts of the copper-stressed yeast cells. The activity was restored in fermentations with glutathione at a copper concentration of 0.16 mM. At low copper concentrations, glutathione decreased ADH activity presumably due to complexation of essential copper amounts. Results provide important information on the use of glutathione as an antioxidant in winemaking to counteract negative effects of copper-rich musts on copper-sensitive yeast strains.


Assuntos
Cobre/metabolismo , Glutationa/metabolismo , Saccharomyces cerevisiae/metabolismo , Álcool Desidrogenase/metabolismo , Cobre/análise , Fermentação , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Vitis/química , Vitis/metabolismo , Vitis/microbiologia , Vinho/análise , Vinho/microbiologia
12.
J Agric Food Chem ; 67(42): 11815-11824, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31550160

RESUMO

Yan73 is a teinturier Vitis vinifera variety with red berry flesh, but the molecular mechanisms underlying its flesh coloration remain unclear. We analyzed the flavonoid metabolic and transcriptome profiles of Yan73 berry red and white flesh using HPLC-ESI-MS/MS and RNA-sequencing technologies. Anthocyanins are the main flavonoids responsible for Yan73 berry flesh color, and the coloration is coordinately regulated by the VvMYBA1 transcriptional activator and VvMYBC2-L1 transcriptional repressor. Furthermore, yeast one- and two-hybrid, dual luciferase, and bimolecular fluorescence complementation assays suggested that VvMYBA1 positively regulates Yan73 berry flesh color via interactions with VvWDR1 and the activation of the VvCHI3, VvOMT, and VvGST4 promoters, whereas VvMYBC2-L1 negatively regulates Yan73 berry flesh color, possibly by competing with the R2R3-MYB transcriptional activators for bHLH partners or by repressing VvOMT and VvGST4 expression. Our findings provide new insights into the molecular mechanisms regulating grape flesh color.


Assuntos
Frutas/química , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas Repressoras/genética , Vitis/genética , Cor , Frutas/genética , Frutas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Vitis/química , Vitis/metabolismo
13.
Sci Total Environ ; 692: 669-675, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539975

RESUMO

Environmental sustainability of viticulture is negatively affected by prolonged droughts. In limestone dominated regions, there is limited knowledge on grapevine water status and on methods for accurate evaluation of actual water demand, necessary to appropriately manage irrigation. During a dry vintage, we monitored plant and soil water relations in old and young vines of Istrian Malvasia on Karst red soil. The vineyard with young vines was additionally subdivided into two areas, based on their soil type, 1) karst silty-clay loam, and 2) mixture of crushed rocks and karst silty-clay loam (stony soil). Seasonal changes in exploited water resources were estimated via analysis of oxygen isotope composition (δ18O) of rainfall, deep soil water, and xylem sap. We hypothesized that plants are able to thrive during drought thanks to the water stored in deep soil layers, while they rely less on superficial soil horizons. Our results show that vines growing on karstic substrates have deep roots securing the use of stable water sources during summer, with consequent favourable plant water status. In fact, both young and mature vines approached the threshold of severe water stress, but never surpassed it, as midday leaf water potentials were >-1.3MPa in all study sites. Vines roots showed flexible water uptake, i.e. the ability to absorb water from deep or shallow soil horizons during drought and after late-summer thunderstorms, which was particularly evident in vines growing on the stony soil. In fact, precipitations of 20mm were enough for plant water status recovery, due to fast infiltration. On the other hand, at least 50mm of rainfall were necessary to induce water status recovery in more compact soil (karst silty-clay loam). Our findings provide new knowledge on the rooting depth and water needs of vines growing on shallow soils overlying fractured limestone bedrock.


Assuntos
Solo/química , Vitis/metabolismo , Água/metabolismo , Secas , Itália , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Vitis/crescimento & desenvolvimento
14.
BMC Plant Biol ; 19(1): 383, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481025

RESUMO

BACKGROUND: Organic acid secretion is a widespread physiological response of plants to alkalinity. However, the characteristics and underlying mechanism of the alkali-induced secretion of organic acids are poorly understood. RESULTS: Oxalate was the main organic acid synthesized and secreted in grapevine (a hybrid of Vitis amurensis, V. berlandieri and V. riparia) roots, while acetate synthesis and malate secretion were also promoted under NaHCO3 stress. NaHCO3 stress enhanced the H+ efflux rate of grapevine roots, which is related to the plasma membrane H+-ATPase activity. Transcriptomic profiling revealed that carbohydrate metabolism was the most significantly altered biological process under NaHCO3 stress; a total of seven genes related to organic acid metabolism were significantly altered, including two phosphoenolpyruvate carboxylases and phosphoenolpyruvate carboxylase kinases. Additionally, the expression levels of five ATP-binding cassette transporters, particularly ATP-binding cassette B19, and two Al-activated malate transporter 2 s were substantially upregulated by NaHCO3 stress. Phosphoproteomic profiling demonstrated that the altered phosphoproteins were primarily related to binding, catalytic activity and transporter activity in the context of their molecular functions. The phosphorylation levels of phosphoenolpyruvate carboxylase 3, two plasma membrane H+-ATPases 4 and ATP-binding cassette B19 and pleiotropic drug resistance 12 were significantly increased. Additionally, the inhibition of ethylene synthesis and perception completely blocked NaHCO3-induced organic acid secretion, while the inhibition of indoleacetic acid synthesis reduced NaHCO3-induced organic acid secretion. CONCLUSIONS: Our results demonstrated that oxalate was the main organic acid produced under alkali stress and revealed the necessity of ethylene in mediating organic acid secretion. Additionally, we further identified several candidate genes and phosphoproteins responsible for organic acid metabolism and secretion.


Assuntos
Proteínas de Plantas/genética , Proteoma/genética , Bicarbonato de Sódio/metabolismo , Transcriptoma , Vitis/genética , Vitis/metabolismo , Ácidos/metabolismo , Compostos Orgânicos/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Proteoma/metabolismo
15.
Plant Sci ; 287: 110172, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481220

RESUMO

Plants must protect themselves from abiotic stresses such as drought, cold, and high salinity. The common thread of all three stresses is that they cause dehydration, which in turn promotes the formation of reactive oxygen species (ROS). Dehydrin proteins (dehydrins) are a large family of proteins that have been identified in nearly all land plants, and whose presence is correlated with plant protection from abiotic stresses. Several dehydrin studies have shown that some dehydrins localize to the nucleus, as well as the cytoplasm, but a functional role for nuclear dehydrins has not yet been determined. We show here that the Vitis riparia dehydrin VrDHN1 localizes to the nucleus and is able to bind to DNA to protect it from damage caused by hydrogen peroxide, an ROS source. We also show that the binding to DNA is not DNA-sequence specific, suggesting that the protein is able to protect any exposed DNA without interfering with its normal function. NMR studies show that the binding is largely driven by the lysine-rich nature of dehydrins located in the conserved K-segments. Unlike other, previously studied dehydrins, VrDHN1 binding to DNA is not enhanced through the presence of metals. Lastly, we demonstrate that the Y-segment does not bind ATP, as has long been proposed.


Assuntos
DNA de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Vitis/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Espectroscopia de Ressonância Magnética , Espécies Reativas de Oxigênio/metabolismo
16.
Plant Cell Rep ; 38(10): 1347-1360, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31414199

RESUMO

KEY MESSAGE: VqERF114 regulates stilbene synthesis by interacting with VqMYB35. Resveratrol is a stilbene, an important class of secondary metabolites that accumulates in some plant species, including grapevine. In the plant, these are involved in the response to attack by plant pathogens and, as a component of the human diet, they offer a range of significant health benefits. Stilbene synthase (STS), the key enzyme responsible for resveratrol synthesis, has been characterised in a small number of plant species. However, the regulatory mechanisms for stilbene synthesis are uncertain. Here, an ERF family transcription factor from Chinese wild Vitis quinquangularis, VqERF114, was characterised as an indirect regulator of stilbene synthesis. A transient overexpression assay of VqERF114 in grapevine leaves led to increased STS expression and stilbene accumulation. However, VqERF114 did not bind to the promoters of VqSTSs but the MYB transcription factor, VqMYB35, did interact with VqERF114. This interaction was confirmed by a yeast two-hybrid assay and bimolecular fluorescence complementation. Furthermore, VqMYB35 showed activation effects on the expressions of VqSTS15, VqSTS28, VqSTS42 and VqSTS46 by binding directly to the MBS elements in their promoters. Co-overexpression of VqERF114 and VqMYB35 resulted in higher VqSTSs expression and more stilbene synthesis. These results demonstrate that VqERF114 regulates stilbene synthesis by interacting with VqMYB35.


Assuntos
Aciltransferases/metabolismo , Fatores de Transcrição/metabolismo , Vitis/metabolismo , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Resveratrol/metabolismo
17.
J Sci Food Agric ; 99(15): 6944-6953, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31414495

RESUMO

BACKGROUND: Dimethyl sulfide (DMS) is a small sulfur-containing impact odorant, imparting distinctive positive and / or negative characters to food and beverages. In white wine, the presence of DMS at perception threshold is considered to be a fault, contributing strong odors reminiscent of asparagus, cooked cabbage, and creamed corn. The source of DMS in wine has long been associated with S-methyl-l-methionine (SMM), a derivative of the amino acid methionine, which is thought to break down into DMS through chemical degradation, particularly during wine ageing. RESULTS: We developed and validated a new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method with a stable isotope dilution assay (SIDA) to measure SMM in grape juice and wine. The application of this new method for quantitating SMM, followed by the quantitation of DMS using headspace-solid phase micro-extraction coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS), confirmed that DMS can be produced in wine via the chemical breakdown of SMM to DMS, with greater degradation observed at 28 °C than at 14 °C. Further investigation into the role of grape juice and yeast strain on DMS formation revealed that the DMS produced from three different Sauvignon blanc grape juices, either from the SMM naturally present or SMM spiked at 50 mmol L-1 , was modulated depending on each of the four strains of Saccharomyces cerevisiae wine yeast used for fermentation. CONCLUSION: This study confirms the existence of a chemical pathway to the formation of DMS and reveals a yeast-mediated mechanism towards the formation of DMS from SMM during alcoholic fermentation. © 2019 Society of Chemical Industry.


Assuntos
Cromatografia Líquida/métodos , Sucos de Frutas e Vegetais/análise , Saccharomyces cerevisiae/metabolismo , Sulfetos/metabolismo , Espectrometria de Massas em Tandem/métodos , Vitamina U/análise , Vitis/química , Fermentação , Frutas/química , Frutas/metabolismo , Frutas/microbiologia , Sucos de Frutas e Vegetais/microbiologia , Odorantes/análise , Sulfetos/análise , Vitamina U/metabolismo , Vitis/metabolismo , Vitis/microbiologia , Vinho/análise
18.
J Agric Food Chem ; 67(35): 9705-9718, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31393722

RESUMO

Antimicrobial resistance is among the most urgent global challenges facing sustainable animal production systems. The use of antibiotics as growth promoters and for infectious disease prevention in intensive animal-farming practices has translated into the selection and spread of antimicrobial resistance genes in an unprecedented fashion. Several multi-resistant bacterial strains have been isolated from food-producing animals, thus constituting an alarming food-safety issue. Many industrial byproducts with potential antimicrobial properties are currently being investigated to identify empirical and affordable solutions/alternatives that can potentially be used in feed for animals. Grape pomace is among such byproducts that gained the attention as a result of its low cost, abundance, and, most importantly, its bioactive and antibacterial properties. This review discusses the recently reported studies with regard to exploring the use of grape pomace (and its extracts) in animal production to control pathogens, along with the promotion of beneficial bacterial species in the gut to ultimately alleviate antibacterial resistance. The review further summarizes realistic expectations connected with grape pomace usage and lists the still-to-be-addressed concerns about its application in animal agriculture.


Assuntos
Ração Animal/análise , Antibacterianos/administração & dosagem , Infecções Bacterianas/veterinária , Extratos Vegetais/administração & dosagem , Vitis/química , Resíduos/análise , Animais , Antibacterianos/química , Antibacterianos/metabolismo , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/metabolismo , Infecções Bacterianas/microbiologia , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Vitis/metabolismo
19.
Int J Mol Sci ; 20(16)2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31434233

RESUMO

Root restriction cultivation leads to early maturation and quality improvement, especially in the anthocyanin content in grapevine. However, the molecular mechanisms that underlie these changes have not been thoroughly elucidated. In this study, four small RNA libraries were constructed, which included the green soft stage (GS) and ripe stage (RS) of 'Muscat' (Vitis vinifera L.) grape berries that were grown under root restriction (RR) and in traditional cultivation (no root restriction, CK). A total of 162 known miRNAs and 14 putative novel miRNAs were detected from the four small RNA libraries by high-throughput sequencing. An analysis of differentially expressed miRNAs (DEMs) revealed that 13 miRNAs exhibited significant differences in expression between RR and CK at the GS and RS stages, respectively. For different developmental stages of fruit, 23 and 34 miRNAs showed expression differences between the GS and RS stages in RR and CK, respectively. The expression patterns of the eight DEMs and their targets were verified by qRT-PCR, and the expression profiles of target genes were confirmed to be complementary to the corresponding miRNAs in RR and CK. The function of Vvi-miR828, which showed the down regulated expression in the RS stage under root restriction, was identified by gene transformation in Arabidopsis. The anthocyanin content significantly decreased in transgenic lines, which indicates the regulatory capacity of Vvi-miR828 in fruit coloration. The miRNA expression pattern comparison between RR and CK might provide a means of unraveling the miRNA-mediated molecular process regulating grape berry development under root restricted cultivation.


Assuntos
Frutas/genética , Frutas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Vitis/genética , Vitis/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , RNA de Plantas/genética , RNA de Plantas/metabolismo , Análise de Sequência de RNA
20.
J Ind Microbiol Biotechnol ; 46(12): 1733-1743, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31420798

RESUMO

Protease-secreting yeasts have broad biotechnological potential for application to various industrial processes, including winemaking. However, this activity is influenced by the yeast response to environmental factors such as nitrogen and protein sources, as are found in grape juice. In this study, the wine-relevant yeast Metschnikowia pulcherrima IWBT Y1123, with known protease-secreting ability, was subjected to different nitrogen-containing compounds to monitor their impact on protease secretion and activity. Protease activity increased above basal levels for haemoglobin-containing treatments, indicating an inductive influence of proteins. On the other hand, treatments containing both haemoglobin and assimilable nitrogen sources led to a delayed increase in protease activity and protein degradation, suggesting a nitrogen catabolite repression mechanism at work. Protease activity and expression were furthermore evaluated in grape juice, which revealed increased expression and activity levels over time as promising results for further investigations into the impact of this yeast on wine properties.


Assuntos
Ácido Aspártico Proteases/metabolismo , Metschnikowia/enzimologia , Ácido Aspártico Proteases/genética , Fermentação , Sucos de Frutas e Vegetais , Metschnikowia/genética , Vitis/metabolismo , Vinho/análise
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