RESUMO
BACKGROUND: 'Karaerik' is a novel table grape (Vitis vinifera L.) native to Turkey and widely cultivated in areas bordering the city of Erzincan. Because of the demonstrated beneficial effects on human health of the grape phenolic composition, the aim of this work was to conduct a detailed profiling of non-anthocyanin phenolic fractions from different grape tissues of the 'Karaerik' table grape. Both qualitative and quantitative characterization of phenolic compounds were achieved using high-performance liquid chromatography-diode array detection-electrospray ionization-tandem mass spectrometry. Total phenolic content and oxygen radical absorbance capacity were also determined to evaluate the antioxidant properties of this table grape. RESULTS: A high number of non-anthocyanin phenolic compounds was identified in 'Karaerik' table grape skins and seeds, including 11 flavonols, six hydroxycinnamic acid derivatives, two stilbenes, several monomeric and dimeric flavan-3-ols and proanthocyanidins. Quercetin-type derivatives dominated the flavonol profile of grape skins, followed by myricetin type. Tartaric acid esters of three acids (caffeic, coumaric and ferulic acids) were the main hydroxycinnamic acid derivatives in this cultivar. Qualitative and quantitative differences were observed in flavan-3-ol composition among the grape tissues. Proanthocyanidins were the most abundant class of phenolic compounds in 'Karaerik' grapes, being mainly located in seeds. Higher antioxidant capacity values were determined in grape seeds, in correlation with the total phenolic content. CONCLUSION: These results provide useful information for a better understanding of phenolic antioxidants from the 'Karaerik' table grape and will contribute to promoting the varietal identity and health-related properties of this fruit. © 2021 Society of Chemical Industry.
Assuntos
Antioxidantes/química , Fenóis/química , Extratos Vegetais/química , Vitis/química , Cromatografia Líquida de Alta Pressão , Frutas/química , TurquiaRESUMO
The effect of cooking on the concentrations of phenolic compounds and antioxidant activities in 33 colored-fleshed potatoes genotypes was evaluated. The phenolic profiles, concentrations, and antioxidant activity were evaluated with a liquid chromatography diode array detector coupled to a mass spectrometer with an electrospray ionization interface (HPLC-DAD-ESI-MS/MS). Eleven anthocyanins were detected; in the case of red-fleshed genotypes, these were mainly acyl-glycosides derivatives of pelargonidin, whereas, in purple-fleshed genotypes, acyl-glycosides derivatives of petunidin were the most important. In the case of the purple-fleshed genotypes, the most important compound was petunidin-3-coumaroylrutinoside-5-glucoside. Concentrations of total anthocyanins varied between 1.21 g kg-1 in fresh and 1.05 g kg-1 in cooked potato and the decreases due to cooking ranged between 3% and 59%. The genotypes that showed the highest levels of total phenols also presented the highest levels of antioxidant activity. These results are of relevance because they suggest anthocyanins are important contributors to the antioxidant activity of these potato genotypes, which is significant even after the drastic process of cooking.
Assuntos
Antioxidantes/farmacologia , Cromanos/antagonistas & inibidores , Cor , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Solanum tuberosum/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Chile , Cromatografia Líquida de Alta Pressão , Culinária , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Análise de Componente PrincipalRESUMO
BACKGROUND: Grape berries exhibit various beneficial health effects due to the potent antioxidant roles of their phenolic compounds. A new Vitis vinifera grape cultivar (Karaerik) grown in Turkey has attracted growing interest due to its antioxidant phenolic compounds, which have still not been investigated. The phenolic/anthocyanin profile needs to be investigated to ascertain its potential health benefits and market value in the region. The present study therefore involves a detailed characterization of the anthocyanin composition of 'Karaerik' grape berries in conjunction with a determination of the antioxidant capacity value of the phenolics present in the skin and the whole berry. RESULTS: Total phenolic compounds (average 8.56 and 2.88 g gallic acid equivalent kg-1 fresh weight) and anthocyanin (7.48 and 1.66 g mv-3-glc equivalent kg-1 fresh weight) contents varied significantly in the skin and whole berry. Malvidin-based anthocyanins made the highest contribution to the pigment content of the berry. Accordingly, the major anthocyanin in the skin (average 42.08 mol%) and whole berry (39.98 mol%) was malvidin-3-glucoside (mv-3-glc). In addition, we found strong evidence of the occurrence of sometimes reported malvidin-3-pentoside and particularly of the not previously reported feruloyl derivative of malvidin-3-(6â³-feruloyl)-glucoside (mv-3-ferglc) for V. vinifera grapes. CONCLUSION: The current study is the first report to profile the anthocyanins of the grape with a detailed description of the rare and novel anthocyanin in V. vinifera grapes. The berry is also a potential source of phenolics/anthocyanins with a high antioxidant capacity value and is worthy of comparison with other V. vinifera grapes. © 2019 Society of Chemical Industry.
Assuntos
Antocianinas/química , Extratos Vegetais/química , Vitis/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Frutas/química , Fenóis/química , Espectrometria de Massas por Ionização por Electrospray , TurquiaRESUMO
BACKGROUND: Strawberries are consumed worldwide. In Chile, strawberry production has been established in Andisols, were phosphorus is scarce. Traditional fertilization (TF) and organic fertilization (OF) have both been established there. This study examined their impact on the polyphenolic content of strawberries. RESULTS: Two anthocyanins were identified by high performance liquid chromatography with diode array detection coupled to mass spectrometry (HPLC-DAD-ESI-MS/MS). The average total anthocyanin concentrations were found to be 651 mg kg-1 fresh weight in 100% OF, which represents a 56% increase compared to fruits that were not fertilized. In the case of flavonols, only quercetin-rhamnoside was identified, and its concentration reached 14.6 mg kg-1 with 100% OF. The ascorbic acid concentration reached 0.54 g kg-1 in 50% TF (a 20% increase over fruits without fertilization, WF). The antioxidant activities slightly increased in the fruits subjected to TF and OF in comparison with WF treatment. CONCLUSION: These results support a management strategy for obtaining the best quality and potential beneficial effects in health by increasing anthocyanins and other polyphenols under OF. © 2018 Society of Chemical Industry.
Assuntos
Antocianinas/química , Antioxidantes/química , Produção Agrícola/métodos , Fertilizantes/análise , Flavonóis/química , Fragaria/química , Chile , Cromatografia Líquida de Alta Pressão , Fragaria/crescimento & desenvolvimento , Frutas/química , Frutas/crescimento & desenvolvimento , Agricultura Orgânica/métodos , Polifenóis/químicaRESUMO
BACKGROUND: Due to the current dominance of a few grape varieties in the wine market, the aim of this work was to study the detailed phenolic and volatile composition, chromatic characteristics, and sensorial properties of red wines elaborated with new Vitis vinifera grapes (Moribel and Tinto Fragoso) identified using the High Perfomance Liquid Chromatography-Diode Array Detector-Electrospray Ionization-Tandem Mass Spectrometry (HPLC-DAD-ESI-MS/MS), Gas Chromatography- Mass Spectrometry (GC-MS), CIELab color space, and Napping ® techniques. RESULTS: Tinto Fragoso wine showed higher phenolic content than Moribel, with more anthocyanins, flavonols, and stilbenes. These wines also contained anthocyanin diglucosides not reported for Vitis vinifera wines. The odor activity values of free volatile compounds were calculated to indicate their influence on wine aroma, the fruity aromas of Moribel standing out particularly. The wines studied were positively evaluated by the tasters. Moribel's sensory profile was characterized by red fruit aromas and Tinto Fragoso showed more aromatic intensity and persistence in the mouth. CONCLUSION: The results obtained from the first characterization of red wines made from novel Vitis vinifera grapes suggest that Moribel and Tinto Fragoso could be appropriate raw materials for the elaboration of quality young red wines. Tinto Fragoso provided wines with sensorial properties different from those of Tempranillo, and could be an alternative to the well known red wines on the market. © 2018 Society of Chemical Industry.
Assuntos
Paladar , Compostos Orgânicos Voláteis/química , Vinho/análise , Antocianinas/química , Cromatografia Líquida de Alta Pressão , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Odorantes/análise , Fenóis/química , Espectrometria de Massas em Tandem , Vitis/químicaRESUMO
Jabuticaba has a high concentration of phenolic compounds, which have a significant antioxidant capacity. Methodologies have been developed to evaluate the ability of plant extracts to fight free radicals such as H2O2, O2â¢-, HOCl, ONOO- and ROOâ¢. Thus, the capacity of deactivation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in peel and seed extracts of five varieties of jabuticaba was evaluated. Sabará peel (SFP) deactivated HOCl with IC50 9.24 µg. mL-1; Paulista seed (PF) deactivated O2â¢- with IC50 16.15 µg. mL-1; Coroada seed (CFP) deactivated ONOO- with IC50 3.84 µg. mL-1; the peel of CFP deactivated ONOO- with IC50 5.88 µg. mL-1; the peel of SFP deactivated the ROO⢠at 918.16 µmol TE. g-1; and Sabará seed deactivated H2O2 with 49.11% inhibition at a concentration of 125 µg. mL-1 of extract. These results demonstrate the high antioxidant potential of this fruit, indicating that it could be extremely beneficial to human health.
Assuntos
Antioxidantes/farmacologia , Myrtaceae/química , Extratos Vegetais/farmacologia , Espécies Reativas de Nitrogênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/antagonistas & inibidores , Frutas/química , Humanos , Extratos Vegetais/química , Sementes/químicaRESUMO
Salinity is one of the most important abiotic stresses, especially in arid regions. Such devastating constraint is converted mainly to oxidative burst. Thus, plants have to develop strategies to scavenge salt-related regenerated oxidant molecules. In the present work, fully aged plants derived from two Vitis vinifera L. cultivars, the Tunisian autochthonous tolerant genotype Razegui and the salt sensitive Syrah, were analyzed regarding their short term response to 100 mM NaCl, in hydroponic cultures. The ratio [ASA/ASA + DHA] was calculated on the basis of the oxidation of ascorbic acid (ASA) into dehydroascorbic acid (DHA) in leaves. Results proved that oxidative stress was generated. This led to the accumulation of malondialdehyde which referred to a lipid peroxidation mainly in the sensitive Syrah. In order to cope with these oxidative disturbances, trans-resveratrol as well as its glucosides trans-piceid and cis-piceid have been de novo synthesized in the sensitive variety. Razegui stilbene concentrations were presented here for the first time and unexpectedly did not show a very important variation during the salt elicitation.
RESUMO
This work aimed to study the antioxidant capacity by different methods, the total content of polyphenols and the stability over time of dried byproducts from Brazilian hybrids and Vitis vinifera varieties. Oven-dried at 50 °C and spray-dried samples were monitored for 90 days of storage. Under testing conditions, BRS Violeta grapes showed the greatest stability and initial high levels of total phenolics and anthocyanins remained almost unchanged until the end of storage period. The same behavior was observed in BRS Violeta freeze-dried skins, seeds and lees (8557, 9520 and 4261 mg GAE/100 g DM, respectively, and 829 and 257 mg mv-3-glc/100 g DM in skin and lees, respectively). In all methodologies tested, BRS Violeta also showed higher values for antioxidant capacity. These results suggest that dried winemaking byproducts can be used as rich sources of polyphenol compounds for industrial extractions with high stability and antioxidant capacity.
Assuntos
Antocianinas/análise , Antioxidantes/análise , Manipulação de Alimentos , Armazenamento de Alimentos , Polifenóis/análise , Vitis/química , Brasil , Análise de Alimentos , Liofilização , Reprodutibilidade dos Testes , VinhoRESUMO
The BRS Carmem grape was developed as an alternative for processing juices and wines. This study aimed to determine the phenolic compounds (PC) in the edible parts of this grape from two harvests-one harvested at ideal maturation time and another when the grapes were still immature-using HPLC-DAD-ESI-MS/MS. Student's t-test was used (α = 0.05) to evaluate differences in the PC content between the edible parts and between the harvests. Both skins showed a predominance of flavonols, anthocyanins, hydroxycinnamic acids derivatives (HCAD) and stilbenes, with higher concentrations for harvest 1 than harvest 2. For both harvests (harvest 1 and harvest 2), the HCAD (mg of caftaric acidâ¢kg fruit-1) was higher in whole grapes (383.98 and 67.09) than in their skins (173.95 and 21.74), with a predominance of trans-caffeic acid for all samples; the flavan-3-ols and proanthocyanidins (mg of (+)-catechinâ¢kg fruit-1) presented higher concentrations in the seeds (flavan-3-ols: 203.20 and 182.71, proanthocyanidins: 453.57 and 299.86) than in the skins (flavan-3-ols: 1.90 and 4.56, proanthocyanidins: 37.58 and 98.92); the stilbenes concentration (µg 3-glc-resveratrolâ¢kg fruit-1) was higher for the seeds from harvest 2 (896.25) than those from harvest 1 (48.67). BRS Carmem grapes contain a phenolic composition complex, and still have a relevant concentration of flavonols, anthocyanins and stilbenes, even when immature.
RESUMO
Although blueberries are widely studied, little information exists on their composition and content of flavonol glycosides. Most studies identify only a few flavonols in blueberries due to separation and identification issues. In the present study, we identified 44 flavonols and chlorogenic acid in 30 samples of Highbush and Rabbiteye blueberry, using HPLC-DAD-ESI-MSn. Highbush group fruits presented mainly quercetin-3-galactoside in their composition, while Rabbiteye group fruits exhibited higher levels of quercetin-3-rhamnoside and quercetin-3-glucuronide. Among the identified flavonols, 8 acylates (acetyl and hydroxymethylglutaroyl) were found, of which quercetin-3-O-[4â³-(3-hydroxy-3-methylglutaroyl)]-α-rhamnoside was found for the first time in blueberries. This compound is exclusive to the cultivars Florida and Powderblue, where it is present in high quantities. Glucuronides of syringetin and laricitrin, and rhamnosyl-galactosides of myricetin, quercetin and isorhamnetin were also found for the first time in blueberries. The Principal Component Analysis showed that blueberry groups can be distinguished based on their phenolic compound profile.
Assuntos
Mirtilos Azuis (Planta)/química , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Fenóis/análise , Análise de Componente Principal , Espectrometria de Massas por Ionização por Electrospray/métodos , Frutas/químicaRESUMO
The aim of this study was to investigate phenolic compounds in peel, pulp and seeds of five different jabuticabas - Plinia trunciflora, "cabinho", P. cauliflora, cultivars "paulista" and "canaã-açu", P. jaboticaba, "sabará" and P. phitrantha, "branca-vinho". In addition to the commonly reported cyanidin-3-glucoside and delphinidin3-glucoside, it was also found the unreported cyanidin-3-coumaroylglucoside in the peels. Flavonols derived from quercetin and myricetin were also detected in jaboticaba peels, along with a wide variety of derivatives of ellagic acid and methyl ellagic acid. The latter derivatives occurred in acylated forms, which were not usually found in jabuticabas. The pulps and seeds of jabuticabas contained large amounts of ellagitannins vescalagin and castalagin, as well as gallic and ellagic acids. The jabuticabas showed small amounts of catechin and gallocatechin. P. jaboticaba showed the highest levels of anthocyanins and flavonols derived from myricetin, and P. phitrantha presented the highest concentration of ellagitannins and flavan-3-ols.
Assuntos
Myrtaceae/química , Fenóis/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Ácido Elágico/análise , Ácido Elágico/química , Flavonóis/análise , Frutas/química , Frutas/metabolismo , Taninos Hidrolisáveis/análise , Myrtaceae/metabolismo , Fenóis/química , Análise de Componente Principal , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
The present manuscript assessed the volatile and sensory profiles of BRS Rúbea and BRS Cora wines elaborated from traditional, grape pre-drying and submerged cap winemaking. The wines contained a higher concentration of acetates (257 mg L-1 to 547 mg L-1) and ethyl and methyl esters (183 mg L-1 to 456 mg L-1) in comparison with Vitis vinifera wines. PCA was applied (explaining 68.43% of the total variance), and the higher concentration of ethyl decanoate and ethyl octanoate, diethyl succinate, hydroxylinalool, and 2-phenyl ethanol was responsible for describing the BRS Rúbea wines as fruity/foxy. They also presented an intense jam note, probably due to their higher concentration of syringol and guaiacol. BRS Cora wines exhibited a vegetal note, possibly due to their higher concentration of 1-hexanol and cis-3-hexenol. Wines from pre-dried grapes presented higher concentration of furfural, assuming a bitter/burned almond aroma. Alternative winemaking accounted for suitable changes in wine aroma, enhancing wine quality.
Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Vitis/química , Compostos Orgânicos Voláteis/química , Vinho/análise , Brasil , Frutas/química , Humanos , Odorantes/análise , OlfatoRESUMO
The ability to obtain different wines with a singular organoleptic profile is one of the main factors for the wine industry's growth, in order to appeal to a broad cross section of consumers. Due to this, white wines made from the novel grape genotypes Albillo Dorado and Montonera del Casar (Vitis vinifera L.) were studied and compared to the well-known Airén at two consecutive years. Wines were evaluated by physicochemical, spectrophotometric, high-performance liquid chromatography-diode array detection-mass spectrometry, gas chromatography-mass spectrometry and sensory analyses. The chromatic characteristics of the new wines were defined by more color purity than Airén, with greenish highlights. In general, the phenolic profile of the Albillo Dorado wines showed a higher flavonol and hydroxycinnamic acid derivative content. Several volatile compounds were determined, and their odor activity values were calculated to determine their impact on wine aroma. A fruity series dominated the wine aromatic composition, but spicier and greener notes characterized the aroma profile of Airén wines. Albillo Dorado and Montonera del Casar were sensory evaluated as wines with a less fresh taste compared to Airén. Unique chemical and sensory profiles were determined for wines made from these novel grape genotypes, providing alternative monovarietal wines to encourage the wine market growth and extend the offer to consumers.
RESUMO
BACKGROUND: The aim of this work was to study the influence of grape berry morphology, especially the seed weight percentage, on the tannin concentration and astringency of red wine. Clusters of Tempranillo, Garnacha, Merlot, and Cabernet Sauvignon were characterized and their seeds were extracted and macerated in a model wine solution. In parallel, we elaborated three types of wines of each cultivar. One wine was made with only grape juice, one wine was made adding the appropriate proportion of seeds to the grape juice, and the last wine was elaborated with the complete destemmed and crushed berries. RESULTS: Merlot and Cabernet Sauvignon grapes, which have higher percentage of seed weight with respect to the berry weight than Tempranillo and Garnacha grapes originated wines with higher tannin concentration and astringency than Tempranillo and Garnacha wines. CONCLUSION: The main conclusion of this study is that the seed weight percentage with respect to the berry weight is one of the main determinants of the final tannin concentration and astringency of red wines.
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Jambolan (Syzigium cumini (L.) Skeels) stands out among the Brazilian fruits that are rich in bioactive compounds with potential for the production of dehydrated product. Therefore, jambolan juice powder was produced by foam mat drying method and stored for 150â¯days at three temperatures (4, 25, 35⯰C). The effect of time, temperature and the interaction of these two factors on the qualitative and quantitative profile of phenolic compounds were determined after analysis of the powders by using HPLC-DAD-ESI-MSn. For the powders submitted to the different study condition, the concentration of flavonols did not differ from the control sample, and only a small reduction in the anthocyanins concentrations was seen (7-9%), only being significantly affected by storage time. Additionally, the molar profiles of these compounds were influenced more by time than storage temperature, however none of the compounds identified was totally degraded. The percentages of antioxidant activity oscillated during the storage time, however, without major losses after 150â¯days at all storage temperatures. The results showed that jambolan juice powder is very stable in terms of anthocyanins and flavonols concentrations at all three temperatures of the storage. This and the attractive color (purplish-red) make it a potential ingredient to enrich differentiated foods.
Assuntos
Antioxidantes/análise , Dessecação/métodos , Qualidade dos Alimentos , Armazenamento de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Fenóis/análise , Syzygium , Cor , Flavonóis/análise , Pós , TemperaturaRESUMO
Grapes are considered to be a major source of phenolic compounds as compared with other fruits. To improve the quality of table grapes, some techniques like thinning can be used. In addition, grape cultivars with distinct characteristics are directly linked to its phenolic profile. This study aimed to identify and quantify the phenolic compound profile and yield of the hybrid 'BRS Vitoria' seedless table grape under different bunch densities, using a combination of solid-phase extraction (SPE) methodologies and analytical high-performance liquid chromatography-diode array detector with tandem mass spectrometry (HPLC-DAD-ESI-MS/MS). A trial was carried out in 2016, in a commercial vineyard at Marialva, state of Parana (South Brazil). Three weeks after anthesis, the following bunch densities were evaluated: 4.0, 4.5, 5.0, 5.5, and 6 bunches per m2 (corresponding to an estimation of 16, 18, 20, 22, and 24 tons ha-1). The randomized block design was used as a statistical model with each treatment was replicated four times, with one vine per plot. Different characteristics were evaluated at harvest, e.g., soluble solids content (SS), total acidity (TA), maturation index (MI = SS/TA), bunch and berry masses, yield, as well hydroxycinnamic acid derivative (HCAD), anthocyanin, flavonol, and flavan-3-ol contents by HPLC-DAD-ESI-MS/MS analysis. The evaluated bunch densities did not interfere with the physicochemical characteristics of the berries, such as SS and MI. Under the density of 6.0 bunches per m2, the highest yield of 25 tons ha-1 was reached. Under all bunch densities, the phenolic profile presented the same compounds, but at different concentrations. Under a density of 5.0 bunches per m2, the compounds belonging to the anthocyanin and flavonol families were present in high concentrations. In contrast, at the densities of 4.0 and 4.5 bunches per m2, there was a reduction in the flavan-3-ol content. With respect to stilbenes, only the trans-piceid and its cis- isomer were detected. However, their concentrations had no significant influence on the evaluated bunch densities.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Fenóis/química , Espectrometria de Massas em Tandem/métodos , Vitis/crescimento & desenvolvimento , Ácidos Cumáricos/química , Produtos Agrícolas , Flavonóis/química , Proantocianidinas/química , Estilbenos/químicaRESUMO
The purpose of this investigation was to assess the grape pigment extraction during red-winemaking. The pigment content and profile of skin, wines and pomace of Vitis vinifera grapes with different pigment profiles Syrah, Marselan and Tannat was thoroughly studied. The p-coumaroylated anthocyanin proportions were 37% in pomace, compared to 19% in skins and just 5% in wines, highlighting their poor extraction. Di-methoxylated based anthocyanins, increased their relative contribution in pomace and wines compared to skins, indicating they were less extracted, but more stable once extracted. Remarkably, the caffeoylated anthocyanins presented significantly higher concentrations in pomace than in skins (1.9 fold on average), suggesting that their synthesis could take place during vinification. Malvidin 3-feruloyl-glucoside was found in the Tannat samples being the first evidence of an anthocyanin acylated with ferulic acid in wine. Pigment extraction was selective depending on anthocyanin B-ring substitution pattern and acylation profile.
Assuntos
Manipulação de Alimentos , Pigmentos Biológicos/análise , Extratos Vegetais/análise , Vitis/química , Vinho/análise , Acilação , Antocianinas/química , Ácidos Cumáricos/química , Frutas/química , Glucosídeos/análiseRESUMO
The chemical oxidation of white wines through the Fenton reaction has been widely studied, wherein the primary species is the hydroxyl radical (OH). This radical possesses high oxidising power and may oxidise the primary components in wines. The Fenton reaction in wines is complex and includes the participation of phenolic compounds, organic acids, and metals. However, there has been no systematic study to date that relates wine composition to OH production in real white wines. In this paper, a multivariate model was generated using the partial least squares (PLS) algorithm, and linear correlations were established between wine composition and OH production. Based on the results, the variables were classified as either pro-oxidants (malic acid, p-coumaric acid, and caffeic acid, % prodelphinidins, procyanidins B1, Mn, Cu, and Zn) or antioxidants (cis-piceid, ellagic acid, gallic acid, proanthocyanins, glucose, and proton concentration). Finally, the pathways by which wine compounds participate in OH production are discussed.
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Radical Hidroxila/metabolismo , Vinho/análise , Antioxidantes/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância de Spin Eletrônica , Radical Hidroxila/análise , Análise dos Mínimos Quadrados , Análise Multivariada , Oxidantes/química , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
This study analyzed the volatile composition and aroma profile of BRS Carmem and BRS Violeta red wines elaborated from traditional and two alternative winemaking procedures: grape pre-drying and submerged cap. The wines contained higher concentration of acetates (ranging from 303â¯mgâ¯L-1 to 905â¯mgâ¯L-1) and ethyl and methyl esters (ranging from 138â¯mgâ¯L-1 to 415â¯mgâ¯L-1). The BRS Carmem wines were described as fruity due to the higher concentration of esters and BRS Violeta wines were described as vegetal mainly due to the higher concentration of terpenes and methoxyphenols. C6 alcohols also influenced the vegetal notes of BRS Violeta wines from traditional and submerged cap procedures and the pre-dried wines also presented a relevant jam note possibly due to the presence of 2-phenylethyl acetate. The changes in winemaking procedures can possibly lead to changes in the aromatic profile of red wines in a positive way, improving the wine aroma quality.
Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Compostos Orgânicos Voláteis/química , Vinho/análise , Fenóis/química , Análise de Componente Principal , Terpenos/química , Vitis/química , Vitis/metabolismo , Compostos Orgânicos Voláteis/análiseRESUMO
Grape pomace is the source of bioactive compounds (anthocyanins, flavonols, flavan-3-ols, and stilbenes) which exhibit antiproliferative actions on cell cultures. We have investigated the antitumoral effects of grape pomace and grape seed extracts on colon cancer cells (Caco-2, HT-29) and fibroblasts. Crude extracts prepared from white and red pomace, and grape seeds, reduced the viability and proliferation of Caco-2. HT-29 cells were resistant to these actions. Purified extracts were then prepared from the same sources and compared with the LDH test; again, all three extracts were active and purified extract from grape seed was the most potent and specific on Caco-2 cells. HT-29 cells were more sensitive to these purified extracts. The biological activity resided almost exclusively in the flavonol and flavan-3-ols subfractions, rather than the anthocyanin subfraction. Preliminary results on the mechanisms involved in these effects revealed downregulation of Myc gene expression in HT-29 and upregulation of Ptg2 in Caco-2 cells.