Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Molecules ; 26(8)2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33920316

RESUMO

Chemical profiling of Buddleja globosa was performed by high-performance liquid chromatography coupled to electrospray ionization (HPLC-DAD-ESI-IT/MS) and quadrupole time-of-flight high-resolution mass spectrometry (HPLC-ESI-QTOF/MS). The identification of 17 main phenolic compounds in B. globosa leaf extracts was achieved. Along with caffeoyl glucoside isomers, caffeoylshikimic acid and several verbascoside derivatives (ß-hydroxyverbascoside and ß-hydroxyisoverbascoside) were identified. Among flavonoid compounds, the presence of 6-hydroxyluteolin-7-O-glucoside, quercetin-3-O-glucoside, luteolin 7-O-glucoside, apigenin 7-O-glucoside was confirmed. Campneoside I, forsythoside B, lipedoside A and forsythoside A were identified along with verbascoside, isoverbascoside, eukovoside and martynoside. The isolation of two bioactive phenolic compounds verbascoside and forsythoside B from Buddleja globosa (Buddlejaceae) was successfully achieved by centrifugal partition chromatography (CPC). Both compounds were obtained in one-step using optimized CPC methodology with the two-phase solvent system comprising ethyl acetate-n-butanol-ethanol-water (0.25:0.75:0.1:1, v/v). Additionally, eight Natural Deep Eutectic Solvents (NADESs) were tested for the extraction of polyphenols and compared with 80% methanol. The contents of verbascoside and luteolin 7-O-glucoside after extraction with 80% methanol were 26.165 and 3.206 mg/g, respectively. Among the NADESs tested in this study, proline- citric acid (1:1) and choline chloride-1, 2- propanediol (1:2) were the most promising solvents. With these NADES, extraction yields for verbascoside and luteolin 7-O-glucoside were 51.045 and 4.387 mg/g, respectively. Taken together, the results of this study confirm that CPC enabled the fast isolation of bioactive polyphenols from B. globosa. NADESs displayed higher extraction efficiency of phenolic and therefore could be used as an ecofriendly alternative to classic organic solvents.

2.
Food Chem ; 355: 129605, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33799238

RESUMO

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.

3.
Food Chem ; 340: 127958, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32916406

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-[4″-(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/química
4.
Foods ; 9(9)2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32932602

RESUMO

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.

5.
Plant Foods Hum Nutr ; 75(4): 532-539, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32783148

RESUMO

Chaura (Gaultheria poeppigii) is a plant species native from Southern Chile, which produces a berry fruit with potential beneficial health effects due to its content of phenolic compounds. The qualitative and quantitative determination of the phenolic compounds from fruits of different colored genotypes (white-, pink- and red-colored) collected from the Osorno volcano and the Conguillío National Park (CNP) in southern Chile were analyzed by mass spectrometry (HPLC-DAD-ESI-MS/MS) and HPLC-DAD, respectively. The total content of phenolic compounds was evaluated by the Folin-Ciocalteu method, and its antioxidant activity by the CUPRAC, TEAC and DPPH methods. Four anthocyanins were detected, with glycosylated derivatives of delphinidin and cyanidin being the most abundant. Fruits with more coloration had higher anthocyanin concentrations. Six flavonols were detected, with quercetin derivatives being the most abundant. The highest concentration of total flavonols reached 0.41 mg g-1 in red colored fruits. The profiles of phenolic compounds showed differences between fruits depending on both the color and the area of collection. Finally, it would be interesting to evaluate the genetic profiles of chaura to determine whether this variation in phenolics and colorations is dependent on the geographical location or dependent on the genotype of the plant.


Assuntos
Frutas , Gaultheria , Antocianinas/análise , Antioxidantes , Chile , Cromatografia Líquida de Alta Pressão , Frutas/química , Espectrometria de Massas em Tandem
6.
Food Sci Nutr ; 8(7): 3442-3455, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32724608

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.

7.
Food Res Int ; 130: 108955, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32156395

RESUMO

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.

8.
Molecules ; 25(6)2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32192041

RESUMO

This study aimed to assess the physicochemical, nutritional and sensory properties of gluten-free breads containing isolated coffee cascara dietary fiber (ICCDF) as a food ingredient. ICCDF was obtained by aqueous extraction. The oil and water holding capacity and the nutritional profile of the novel ingredient were determined. Its safety was certificated by analysis of ochratoxin A, caffeine and gluten. Gluten-free bread formulations were prepared enriching a commercial bakery premix in rice protein (8%) and ICCDF (3% and 4.5%). Nutritional profile of the novel gluten-free breads (dietary fiber, protein, amino acids, lipids, fatty acid profile and resistant starch), as well as bread volume, crumb density, moisture, firmness, elasticity and color intensity were determined. A sensory quantitative descriptive analysis of the breads was conducted using eight trained panelists. New breads showed significantly higher (p < 0.05) content of dietary fiber and protein than the control bread. The addition of ICCDF allowed increasing dough yield, a less crumb firmness and a higher crumb elasticity. The nutrition claims "source of protein and high in dietary fiber" were assigned to the new formulations. In conclusion, a certificated gluten-free bread with improved nutritional and physicochemical properties and good sensorial profile was obtained.

9.
Plants (Basel) ; 9(2)2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32069868

RESUMO

Peumus boldus Mol., is a Chilean medicinal tree used for gastrointestinal and liver diseases. Such medicinal properties are associated with the presence of bioactive flavonoids and aporphine alkaloids. In this study, a new green and efficient extraction method used seven natural deep eutectic solvents (NADES) as extraction media. The extraction efficiency of these NADES was assessed, determining the contents of boldine and total phenolic compounds (TPC). Chemical profiling of P. boldus was done by high-performance liquid chromatography coupled to photo diode array detector and electrospray ion-trap mass spectrometry (HPLC-PDA-ESI-IT/MS) and electrospray ionization quadrupole time-of-flight high-resolution mass spectrometry (HPLC-ESI-QTOF-MS). Among the NADES tested, NADES4 (choline chloride-lactic acid) and NADES6 (proline-oxalic acid) enable better extraction of boldine with 0.427 ± 0.018 and 2.362 ± 0.055 mg of boldine g-1 of plant, respectively. Extraction of boldine with NADES4 and NADES6 was more efficient than extractions performed with methanol and water. On the other hand, the highest TPC were obtained using NADES6, 179.442 ± 3.79 mg of gallic acid equivalents (GAE g-1). Moreover, TPC in extracts obtained with methanol does not show significant differences with NADES6. The HPLC-PAD-MS/MS analysis enable the tentative identification of 9 alkaloids and 22 phenolic compounds. The results of this study demonstrate that NADES are a promising green extraction media to extract P. boldus bioactive compounds and could be a valuable alternative to classic organic solvents.

10.
Food Res Int ; 128: 108750, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31955732

RESUMO

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 150 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 150 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.

11.
Food Chem ; 311: 126025, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31869649

RESUMO

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 , Olfato
12.
J Sci Food Agric ; 100(3): 1301-1310, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31743440

RESUMO

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-(6″-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 , Turquia
13.
Molecules ; 24(21)2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31694238

RESUMO

Glycosylated flavanols (monoglycosides and diglycosides) in skin and seed extracts of Vitis vinifera grapes grown in Castilla-La Mancha (Spain) were investigated using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-ESI-QQQ-MS/MS). Six grape varieties (Airén, Tempranillo, the recently identified Albillo Dorado, Montonera del Casar, Moribel, and Tinto Fragoso) were studied over two consecutive years (2016 and 2017). A total of twenty monomeric flavanol monoglycosides, four diglycosylated monomers, and three dimeric flavanol monoglycosides were detected in all grape samples. The diversity observed in the composition of glycosylated flavanol in the grape berries suggests a strong influence of variety and grape tissue (skin or seed). Monomeric flavanol glycosides were more abundant in grape seed extracts, in contrast with monoglycosylated dimeric forms. In addition, the glycosylated flavanol content was related to berry color in grape skins, with higher concentrations measured in black grape varieties.


Assuntos
Flavonoides/química , Glicosídeos/química , Extrato de Sementes de Uva/química , Sementes/química , Vitis/química , Cromatografia Líquida de Alta Pressão/métodos , Polifenóis/química , Espanha , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Vinho
14.
Food Sci Nutr ; 7(9): 2948-2957, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31572588

RESUMO

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.

15.
Food Res Int ; 125: 108556, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554044

RESUMO

Lipids are important constituents of plant and animal cells, being essential due to their biological functions. Despite the significant role of these compounds in grape berries, knowledge of grape lipid composition is still limited. This study addresses the free fatty acid composition and other lipids in skins and seeds of several Vitis vinifera grape cultivars using LC-MS/MS. A different profile of free fatty acids was determined in the grape tissues, showing a higher proportion of unsaturated fatty acids in seeds (ca. 60%). Lignoceric acid was one of the main free saturated fatty acids found in grape skins, together with palmitic and stearic acids. Berry skins showed similar ranges of C18-unsaturated fatty acids, whereas linoleic acid was predominant in the seed fatty acid composition. Higher content of glycerophospholipids was determined in grape seeds. Uvaol and oleanolic acid were only quantified in skins (1.5-3.9 and 38.6-57.6 mg/kg fresh weight, respectively). These preliminary results suggest a certain diversity in grape lipids according to their location in the berry tissues and cultivar, providing useful information for the fermentation process due to their role in wine sensory profile and yeast growth.


Assuntos
Cromatografia Líquida/métodos , Ácidos Graxos não Esterificados/análise , Lipídeos/análise , Sementes/química , Espectrometria de Massas em Tandem/métodos , Vitis/química
16.
Molecules ; 24(18)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547424

RESUMO

The Argentinean Patagonia berries Berberis microphylla, Berberis darwinii, and Fragaria chiloensis ssp. chiloensis f. patagonica were investigated for their polyphenol content and composition by means of liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry. The in vitro antioxidant activity and inhibition of metabolic syndrome-associated enzymes (α-glucosidase, α-amylase, and lipase) of the fruit extracts was assessed. The most complex polyphenol profile was found in the Berberis samples, with 10 anthocyanins, 27 hydroxycinnamic acids, 3 proanthocyanidins, 2 flavan-3-ol, and 22 flavonols. Fragaria presented four anthocyanins, nine ellagitannins, two proanthocyanidin dimers, one flavan-3-ol, and five flavonols. The Berberis samples showed the best antioxidant capacity, while Fragaria displayed better activity against α-glucosidase and lipase. The phenolic content and composition of the Argentinean Patagonia berries was similar to that reported for Chilean samples but with some chemical differences between Eastern (Argentina) and Western (Chile) Patagonia. The data obtained supports the consumption of these berries as sources of beneficial polyphenols.


Assuntos
Antioxidantes/farmacologia , Berberis/química , Fragaria/química , Polifenóis/análise , Polifenóis/farmacologia , Antocianinas/análise , Antioxidantes/análise , Argentina , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/análise , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Taninos Hidrolisáveis/análise , Síndrome Metabólica/enzimologia , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Espectrometria de Massas por Ionização por Electrospray , alfa-Amilases/antagonistas & inibidores
17.
Food Chem ; 298: 124971, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260997

RESUMO

The BRS Violeta grape presents pulp and skin with high content of phenolic compounds (PCs) and intense purplish color. It was used as raw material for the production of juice and dehydrated products using foam mat drying at 60, 70 and 80 °C and freeze drying (control). HLPC-DAD-ESI-MSn allowed the evaluation of the quantitative and qualitative changes of the main PCs (anthocyanins, flavonols and hydroxycinnamic acid derivatives (HCAD)) present in the grapes during the processing. The use of the steam extraction method to obtain grape juice allowed a greater extraction of flavonols and, mainly derivatives of hydroxycinnamic acids, when compared with anthocyanins. Drying at 70 °C was the most suitable for the preservation of the PCs and, at the same time, for the reduction of the processing time. The powdered products presented considerable concentrations of total PCs (3-5 mg/g) and antioxidant activity (32-79 (DPPH) or 17-27 (FRAP) mg/g).


Assuntos
Antioxidantes/análise , Indústria de Processamento de Alimentos/métodos , Sucos de Frutas e Vegetais , Fenóis/análise , Vitis/química , Antocianinas/análise , Cromatografia Líquida de Alta Pressão , Cor , Ácidos Cumáricos/análise , Flavonóis/análise , Liofilização , Sucos de Frutas e Vegetais/análise , Pós , Espectrometria de Massas por Ionização por Electrospray , Temperatura
18.
Food Chem ; 295: 350-360, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174768

RESUMO

The detailed phenolic composition of different berry parts from two novel V. vinifera L. red grape genotypes (Moribel and Tinto Fragoso), together the well-known Tempranillo, was established using high performance liquid chromatography-diode array detection-electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS/MS) over two consecutive vintages (2016 and 2017). More than 50 phenolic compounds were identified and quantified: 25 anthocyanins, 17 flavonols, 7 hydroxycinnamic acid derivatives, 2 stilbenes, and several flavan-3-ols. As far as we know, some anthocyanin and flavonol dihexosides were reported for the first time in V. vinifera L. grapes. Application of Principal Component Analysis (PCA) to experimental data showed a good separation of the novel grape genotypes and Tempranillo according to the phenolic profile of skins and seeds, mainly based on the proportion of trisubstituted anthocyanin derivatives, flavonols and flavan-3-ols, being a useful tool to differentiate these grape varieties.


Assuntos
Fenóis/análise , Vitis/química , Vitis/genética , Antocianinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Flavonóis/análise , Análise de Alimentos/métodos , Análise de Alimentos/estatística & dados numéricos , Frutas/química , Frutas/genética , Genótipo , Análise de Componente Principal , Sementes/química , Sementes/genética , Espectrometria de Massas por Ionização por Electrospray , Estilbenos/análise , Espectrometria de Massas em Tandem
19.
Food Chem ; 291: 167-179, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31006456

RESUMO

The berries from the native Chilean Gaultheria phillyreifolia and G. poeppigii are appreciated for their sweet taste and aroma. Fruits from both species were investigated for their secondary metabolite composition and antioxidant activity. The extracts were submitted to membrane chromatography to separate anthocyanins from copigments. Four anthocyanins were isolated by counter-current chromatography (CCC) and identified as cyanidin galactoside, cyanidin arabinoside, delphinidin galactoside and delphinidin arabinoside. From the copigments, CCC allowed the separation of quercetin(Q)-3-arabinoside, Q-3-rutinoside Q-3-rhamnoside and 3-caffeoylquinic acid. Additionally, the iridoids monotropein-10-trans-coumarate, monotropein-10-trans-cinnamate and 6α-hydroxy-dihydromonotropein-10-trans-cinnamate were isolated. The latter two iridoids are reported here for the first time. Some 34 other compounds were tentatively identified by HPLC-DAD-ESI-MSn. The antioxidant activity showed differences between anthocyanins and copigments from both species. Main compounds were quantified and submitted to a Partial-Least Square Discriminant Analysis (PLS-DA). This is the first report on the isolation of phytochemicals from the selected Chilean Gaultheria species.


Assuntos
Antioxidantes/química , Gaultheria/química , Iridoides/química , Polifenóis/química , Chile , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Análise Discriminante , Frutas/química , Frutas/metabolismo , Gaultheria/metabolismo , Iridoides/isolamento & purificação , Análise dos Mínimos Quadrados , Extratos Vegetais/química , Polifenóis/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray
20.
J Agric Food Chem ; 67(13): 3583-3594, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30821976

RESUMO

Phenolic compounds of eight pistachio ( Pistacia vera L.) cultivars and their residual cakes and virgin oils (screw pressing) were studied using high-performance liquid chromatography-diode array detection-electrospray ionization-tandem mass spectrometry. A total of 25 compounds were identified and quantified for pistachio nuts and residual cakes, with the presence of five flavonols, six flavanols, and one gallotannin being reported for the first time. Total phenolics in pistachio nuts showed a concentration from 1359 mg/kg (Kastel) to 4507 mg/kg (Larnaka). Flavanols were the most abundant phenolics, at about 90%, with resulting procyanidin B1 and gallocatechin being the main phenolics, depending upon the cultivar. Other phenolic groups, such as anthocyanins (from 54 to 218 mg/kg), flavonols (from 76 to 130 mg/kg), flavanones (from 12 to 71 mg/kg), and gallotannins (from 4 to 46 mg/kg), were also identified. Residual cakes presented the same phenolic profile but with a concentration almost double because of the concentration effect caused by the oil separation. Virgin pistachio oils showed a very low phenolic content, with eriodyctiol being the only compound identified.


Assuntos
Antioxidantes/química , Fenóis/química , Pistacia/química , Extratos Vegetais/química , Óleos Vegetais/química , Resíduos/análise , Antioxidantes/isolamento & purificação , Fenóis/isolamento & purificação , Pistacia/classificação , Extratos Vegetais/isolamento & purificação , Sementes/química , Sementes/classificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...