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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.

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.

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.

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 (β-hydroxyverbascoside and β-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.

Flavonols are a class of polyphenol compounds whose importance for wine quality has increased as their structures and properties have become better understood. Here, the acetylated and p-coumaroylated derivatives of the flavonol 3-O-glucosides of isorhamnetin, laricitrin and syringetin have been identified for the first time in Vitis vinifera grape skins and wines. First, the MS2 fragmentation patterns of the new flavonol derivatives showed a main signal attributable to the expected flavonol aglycone. In the p-coumaroylated derivatives, the signal corresponding to the intermediate loss of the phenolic acid was also observed. The structures of the aglycones were confirmed by their respective MS3 experiments that matched with those obtained from authentic standards of the aglycones. In addition, the fragmentation signals corresponding to the aglycone radical ions generated through homolytic cleavage assisted identification, and could support future studies of flavonoid compounds by ESI-MS. Using an HPLC-ESI-Q-ToF system, the observed m/z values of the compounds being studied were successfully matched with the expected formula. Surprisingly, just the minority methoxylated flavonol glucosides presented acylation, suggesting a high substrate specificity of the acyltransferases implicated in their synthesis. These findings show higher diversity of grape and wine flavonols. Additional studies and isolation strategies need to be followed to further characterize these metabolites as to test their presence in other grape varieties and it wines.

The objective of this work was to contribute to the knowledge of the relationship between phenolic composition and the temperature of maceration/fermentation on Petit Verdot red wines, which were made with three treatments (17°C, 21°C, and 25°C). The phenolic compounds of Vitis vinifera cv. Petit Verdot wines elaborated at different maceration/fermentation temperatures were determined and compared by high-performance liquid chromatography coupled with diode array detector and electrospray ionization mass spectrometry. A total of 45 phenolic compounds were detected in all wines. The phenolic composition was affected by the temperature of maceration. The increment of maceration/fermentation temperature had a positive effect on the total concentration of the phenolic compounds and chromatic characteristics of these wines. The colour of Petit Verdot young red wines showed more colour intensity and their luminosity descended due to the increase in temperature. The highest total content of anthocyanins was determined in wines macerated at 21°C. However, other groups of phenolic compounds (flavonols, proanthocyanidins, and stilbenes) increased their total content by raising the maceration/fermentation temperature, reaching maximum values at 25°C.

Targeted analysis based on high performance liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS/MS) has been applied to determine genotypic effect in the phenolic composition of novel white grapes (Vitis vinifera L.). For this purpose, the recently identified white grape genotypes Albillo Dorado and Montonera del Casar were comprehensively profiled and compared to cultivar Airen at two consecutive years (2016 and 2017). Several phenolic compounds were quantified in berry parts and arranged into the following classes: flavonols, flavan-3-ols, hydroxycinnamic acid derivatives and stilbenes. In order to establish the degree of dissimilarity between grape genotypes, data obtained were subjected to statistical analysis included a Principal Component Analysis that provided a good separation according to flavonols, hydroxycinnamic acid derivates and flavan-3-ols from different grape tissues. The approach reported here may serve to clarify the varietal typicity of these new white grape genotypes for producers and consumers, defining their identity and position on the market.

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 &plusmn, 0.018 and 2.362 &plusmn, 0.055 mg of boldine g&minus, 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 &plusmn, 3.79 mg of gallic acid equivalents (GAE g&minus, 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.

Aim: The aim of the study was to investigate the stilbene composition of grapes and wines of the Vitis vinifera cultivars Tannat, Marselan and Syrah cultivated in Uruguay. The effects of delaying the harvest on stilbene concentrations were determined, and the stability of stilbenes during wine storage was assessed.Methods and results: Stilbene concentrations were determined in the grapes and wines of two vintages (2015 and 2016) and two harvest dates for each cultivar. Vinification was carried out by traditional maceration, and samples of the wines of each vintage were analysed in the period from 3 months after devatting to up to 24 months later. After solid-phase extraction, stilbenes were identified and quantified by HPLC-ESI-MS/MS using a multiple reaction-monitoring approach. In the grape berries, stilbene concentrations were between 1.6 and 7.7 mg/kg, depending on grape cultivar, growing season, and in Syrah, harvest date. In the wines, stilbene concentrations were initially between 0.9 and 5.0 mg/L, being highest in Syrah, lowest in Marselan, and intermediate in Tannat. Stilbene concentrations in the Marselan wines were lower than expected based on stilbene concentrations in the grapes from which they were produced, suggesting poor extraction during winemaking. Total stilbene concentrations remained very stable during the analytical period.Conclusions: Delaying the harvest does not necessarily increase the stilbene content of grapes, but it can do so significantly, as shown for Syrah. For some grape cultivars, such as Marselan, poor extraction of stilbenes during winemaking can limit their concentrations in the resulting wines.Significance and impact of the study: The results of this study show the relevance of grape cultivar, degree of maturity and storage time may have into stilbenes. They provide reference data on the stilbene composition of grapes and wines produced under Uruguayan winegrowing conditions. The high stability of stilbenes during wine storage is relevant for consumers interested in red wine as a source of bioactive compounds. In memory of Prof. Isidro Hermosín-Gutiérrez.

Determining the harvest date of table grapes is very important to achieve high-quality bunches with adequate soluble solids content, low titratable acidity, and high concentrations of polyphenols. Table grape consumption has increased worldwide due to its phenolic compound content and its beneficial effects on human health. Thus, this study aimed to characterize the phenolic ripening of ‘BRS Vitoria’ seedless table grapes at different ripening stages using HPLC–DAD–ESI-MS/MS. For this purpose, a trial was carried out during 2016 in a commercial vineyard of ‘BRS Vitoria’ seedless grape located in Marialva, state of Parana (Southern Brazil). Berry samples were assessed weekly, starting at veraison until full ripeness. At each ripening stage, the berries were analyzed to determine their physicochemical characteristics and polyphenolic profile. It was observed that ‘BRS Vitoria’ grapes can be harvested approximately 28 days after veraison, when the berries reach soluble solids content higher than 15°Brix and low titratable acidity. The grapes presented a typical anthocyanin profile of hybrid grapes, composed of 3-glucoside and 3,5-diglucoside derivatives. In addition, pelargonidin traces were also observed, and this aglycone is rarely detected in grapes. The total anthocyanin concentration, as malvidin-3,5-diglucoside equivalents, is close to 596.9 mg kg−1. Concerning flavonols, myricetin and quercetin are detected in greater proportions, and this cultivar can also be considered an important source of proanthocyanidins.

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&mdash, tandem mass spectrometry (UHPLC-ESI-QQQ-MS/MS). Six grape varieties (Air&eacute, n, 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.