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[Display omitted] • A one-step leaching process for spent LiCoO 2 based on the mechanochemical method. • The new application of grape skins promotes the leaching of spent LiCoO 2. • Effect of mechanical activation on the interfacial reaction of spent LiCoO 2. • The mechanism of mechanochemical leaching was analyzed by BET, PSD, XRD, and XPS. A one-step system based on mechanochemical activation and the use of grape skins (GS) was proposed to recover metals from lithium-ion batteries (LIBs) cathode waste. The effects of the ball-milling (BM) speed, BM time, and quantity of added GS on the metal leaching rate were explored. The spent lithium cobalt oxide (LCO) and its leaching residue before and after mechanochemistry were characterized by SEM, BET, PSD, XRD, FT-IR, and XPS analysis. Our study shows that mechanochemistry promotes the leaching efficiency of metals from LIBs battery cathode waste by changing the cathode material properties (that is, reducing the LCO particle size (12.126 μm ∼ 0.0928 μm), increasing the specific surface area (0.123 m2/g ∼ 15.957 m2/g), enhancing the hydrophilicity and surface free energy (57.44 mN/m2 ∼ 66.18 mN/m2), promoting the generation of mesoporous structures, refining grains, disrupting the crystal structure, and increasing the microscopic strain, while deflecting the binding energy of the metal ions). A green, efficient and environmentally friendly process for the harmless and resource-friendly treatment of spent LIBs has been developed in this study. [ABSTRACT FROM AUTHOR]

To develop an efficient method for degradation of grape seed and skin proanthocyanidins polymers into oligomers, an optimized sulphurous acid degradation conditions for grape seed with the temperature of 60 °C, reaction time of 60 min and sample-sulphurous acid ratio of 1:0.2, and for grape skin with the temperature of 40 °C, reaction time of 60 min and sample-sulphurous acid ratio of 1:0.2, were established. Afterwards, HSCCC and prep-HPLC were used to fractionate and isolate individual proanthocyanidin oligomers from the degradation products. Total of ten dimeric or trimeric procyanidins were obtained, and most of them presented high yield (from 0.7 mg to 13.6 mg per run in grape seed and from 0.5 mg to 4.1 mg per run in grape skin) and high purity (over 90%). The proposed method provides a new way for large preparation of oligomeric proanthocyanidins from naturally abundant and wasted polymeric ones. [ABSTRACT FROM AUTHOR]

In this work, carbon nanodots were synthesized using grape skin as raw material by one step hydrothermal method under optimized experimental conditions. The carbon nanodots were characterized by TEM, fluorescence, UV, IR and XPS. The average particle size of the carbon particles was 4.0 ± 1.5 nm. When excited at 430 nm, the carbon nanodots showed strong green fluorescence of 522 nm which was dependent on the excitation wavelength. The fluorescence quantum yield reached 18.67%. Stability and anti-photobleaching properties were ideal. Picric acid quenched the fluorescence of the carbon nanodots in the phosphate buffer solution at pH = 7.4, and a method of high sensitivity and selectivity to detect picric acid was established. The linear range was 0.06–79.4 μM, the correlation coefficient was 0.998, and the detection limit was 10 nM (S/N = 3). The method was successfully applied to the detection of picric acid in real water samples. The recoveries fell in the range of 95.64%–104.2% and the RSD was 0.26%–0.74%. [ABSTRACT FROM AUTHOR]

[Display omitted] • The V-shaped canopy led to larger leaf area compared to the T -shaped and VSP canopies.. • The V-shaped canopy was more favorable for flavonoid and phenolic acid accumulation. • Individual flavonoids and phenolics (e.g., afzelin and gentisic acid) were revealed. • UGT88A1 , CCOMT , CHI , CYP98A2 , and COMT may be the key genes. The flavonoids and phenolic acids in grape berries greatly influence the quality of wine. Various methods are used to shape and prune grapevines, but their effects on the flavonoids and phenolic acids remain unclear. The flavonoids and phenolic acids in the berry pericarps from grapevines pruned using three types of leaf canopy, namely, V-shaped, T -shaped, and vertical shoot-positioned (VSP) canopies, were compared in this study. Results showed that the V-shaped canopy was more favorable for the accumulation of flavonoids and phenolic acids. Transcriptome and metabolome analyses revealed that the differentially expressed genes (DEGs) and differentially regulated metabolites (DRMs) were significantly enriched in the flavonoid and phenylpropanoid biosynthesis pathways. A total of 96 flavonoids and 32 phenolic acids were detected among the DRMs. Their contents were higher in the V-shaped canopy than in the T -shaped and VSP canopies. Conjoint analysis of transcriptome and metabolome showed that nine DEGs (e.g., cytochrome P450 98A9 and 98A2) were significantly correlated to nine phenolic acids (e.g., gentisic acid and neochlorogenic acid) and three genes (i.e., chalcone isomerase , UDP-glycosyltransferase 88A1 , and caffeoyl-CoA O-methyltransferase) significantly correlated to 15 flavonoids (e.g., baimaside and tricin-7-O-rutinoside). These genes may be involved in the regulation of various flavonoids and phenolic acids in grape berries, but their functions need validation. This study provides novel insights into the effects of leaf canopy on flavonoids and phenolic acids in the skin of grape berries and reveals the potential regulatory networks involved in this phenomenon. [ABSTRACT FROM AUTHOR]

Highly soluble maltodextrin-encapsulated grape skin phenolics comprising anthocyanins and less hydrophilic flavonoids were added as an ingredient to apple puree. Upon formulation, heat treatments were applied to achieve 3–14 decimal reductions (D) of the target microorganism ( Alicyclobacillus acidoterrestris ). A storage study was performed at 15–35 °C for 1 month. Monomeric anthocyanins were retained at 100% after the 3 D treatment, while anthocyanin retention decreased to 72% with increasing heating intensity until 14 D. During storage, the concentration of monomeric anthocyanins decreased following first-order kinetics (k 25 °C = 34.4 d −1 , activation energy = 51.0 kJ/mol). The flavanols were more stable than the monomeric anthocyanins. The hydroxycinnamic acid, dihydrochalcone and flavonol contents did not change. The fortified puree had a two-fold higher reducing capacity with respect to apple puree. Overall, this ingredient could meet the industrial demand for sustainable colouring agents and health promoting compounds. [ABSTRACT FROM AUTHOR]

Grape pomace is a winemaking by-product that can be used to extract oenological tannins. Recently, some grape skin tannins were shown to contain very high amounts of two polyfunctional thiol precursors (3- S -glutathionylhexan-1-ol, 3- S -cysteinylhexan-1-ol) whose free forms are responsible for appreciated tropical-like flavours. This study shows that an oxidative treatment (no SO 2 ) of white grape pomace and the presence of grape leaves and stems can increase the content of the above mentioned precursors. Moreover, it shows significant differences between Sauvignon Blanc, Gewuerztraminer and Mueller-Thurgau grape pomace for the 3-mercaptohexan-1-ol precursors and 4- S -cysteinyl-4-methylpentan-2-one. The grape cultivar is crucial, but the technological ability of enhancing the level of the volatile thiol precursors simply by treating the grape marc in different ways is a promising and powerful tool for the production of potentially flavouring tannins intended for food and beverage industry. [ABSTRACT FROM AUTHOR]

Conventional extraction techniques for plant phenolics are usually associated with high organic solvent consumption and long extraction times. In order to establish an environmentally friendly extraction method for grape skin phenolics, deep eutectic solvents (DES) as a green alternative to conventional solvents coupled with highly efficient microwave-assisted and ultrasound-assisted extraction methods (MAE and UAE, respectively) have been considered. Initially, screening of five different DES for proposed extraction was performed and choline chloride-based DES containing oxalic acid as a hydrogen bond donor with 25% of water was selected as the most promising one, resulting in more effective extraction of grape skin phenolic compounds compared to conventional solvents. Additionally, in our study, UAE proved to be the best extraction method with extraction efficiency superior to both MAE and conventional extraction method. The knowledge acquired in this study will contribute to further DES implementation in extraction of biologically active compounds from various plant sources. [ABSTRACT FROM AUTHOR]

The aim of this work was to address the air-borne application of power ultrasound in the convective drying of grape skin, a by-product of winemaking. For that purpose, convective drying experiments were carried out on red grape skin at 40, 50, 60 and 70 °C with (21.7 kHz, 45 W) and without power ultrasound application. The kinetic intensification was evaluated by modeling the drying kinetics using empirical and diffusion models. Meanwhile, the quality of the dried product was determined by obtaining ethanolic extracts and assessing the total phenolic content and antioxidant capacity by means of the FRAP method. Moreover, individual polyphenols were identified by HPLC-DAD-ESI-MS/MS and a Partial Component Analysis (PCA) was performed in order to elucidate the relationships between the measured variables that were related to bioactive content. Both temperature and ultrasound application had a significant ( p < 0.05) influence on the drying kinetics, which were satisfactorily described by both the Peleg and diffusion models. In addition, both factors significantly ( p < 0.05) influenced the total phenolic concentration and antioxidant capacity of the extracts. Ultrasound application reduced the antioxidant potential, probably due to oxidase activation and cell degradation. Bioactive potential, on the other hand, was increased as a consequence of high-temperature drying, leading in particular to a greater release of malvidin 3-O-β-D-galactoside. [ABSTRACT FROM AUTHOR]

Organic toxins are persistent chemicals of global concern capable of accumulating in environment and food. Surface enhanced Raman spectroscopy (SERS) is a promising technique that facilitates onsite detection of organic toxins. However, the fabrication of a SERS substrate is complicated and difficult to provide flexibility, fastness and cost-effectiveness. This study aims to develop a paper-based SERS method using grape skin-gold nanoparticles/graphene oxide (GE-AuNPs/GO) as SERS substrate and evaluate its efficiency with rhodamine 6G (Rh6G) as a model organic toxin and a real water and food contaminant. GE-AuNPs synthesized by green method using grape skin waste extract and GE-AuNPs/GO showed a surface plasmon resonance at 536 and 539 nm, particle size 18.6 and 19.5 nm, and zeta potential −44.6 and −59.7 mV, respectively. Paper-based SERS substrates were prepared by coating a hydrophobic thin-film of 30% polydimethylsiloxane solution in hexane on Whatman no. 1 filter paper, followed by drop-casting GE-AuNPs or GE-AuNPs/GO and drying. The SERS signals of Rh6G showed an enhancement factor of 5.8 × 104 for GE-AuNPs and 1.92 × 109 for GE-AuNPs/GO, implying that a combination of electromagnetic surface plasmon, charge transfer and molecular resonances may be responsible for a higher enhancement of signal by the latter. A low detection limit of 7.33 × 10−11 M in the linear range of 10−11–10−5 M was obtained for GE-AuNPs/GO, while the relative standard deviation of repeatability and reproducibility was 9.6 and 12.6%, respectively. Paper-based GE-AuNPs/GO SERS substrate was highly stable as <20% loss in efficiency was shown over a 60-day storage period. Application to real samples showed a high recovery of Rh6G from tap water (93.9–100.8%) as well as food samples such as red chilli powder (91.0–95.4%), red glutinous rice ball (96.6–98.3%) and tomato ketchup (98.9–102.3%) after QuEChERS extraction. Collectively, the developed paper-based GE-AuNPs/GO can be a potential substrate for sensitive onsite detection of rhodamine 6G by SERS method. [Display omitted] • Grape skin-AuNPs/GO based paper SERS method was developed for rhodamine 6G detection. • Synthesized nanostructures were characterized by UV–Visible, Raman, zeta potential and TEM. • High enhancement factor was shown for GE-AuNPs (104) and GE-AuNPs/GO (109). • Low detection limit and high repeatability/reproducibility were obtained for GE-AuNPs/GO. • High recovery from tap water, chilli powder, glutinous rice ball and tomato ketchup was shown. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new anthocyanin trimer pigment was detected in grapes and young Port wines. [•] The new compound was characterised using LC–MS and NMR spectroscopy techniques. [•] The main feature is the presence of two A-type linkages. [Copyright &y& Elsevier]

Abstract: In this study seven published methods of extraction of skin free and bound volatile compounds have been compared. The free and bound volatiles were separated by solid phase extraction (SPE) and then analysed by gas chromatography coupled with mass spectrometry (GC–MS). The results showed that the extraction of volatile compounds from grapes is highly affected by extraction solution features. The solution at pH 3.2 and 0% ethanol resulted the most effective as it led to the extraction of a higher number and amount of free and glycosilated volatile compounds. The selected extraction method of grape skin and the process of pulp juice were validated for quantitative determination of a wide range of grape aroma compounds. A total of 37 free and bound grape aroma compounds were quantified by GC–MS in selective ion monitoring modality (SIM). Among them, 26 volatile compounds resulted validated in grape skin and pulp juice. [Copyright &y& Elsevier]

Abstract: Four extraction techniques—namely, conventional maceration, ultrasound-assisted extraction, microwave-assisted extraction, and superheated liquid extraction (SHLE)—have been compared to evaluate their suitability to obtain valuable compounds from a raw material traditionally of scant interest: grape skin residues from ethanol-distillation. With this aim, red- and white-grape skins were separated from the rest of the pomace residue and subjected to extraction with 1:1 ethanol–acidic water as extractant in order to obtain the largest possible number of valuable compounds from this material, which has so far been used only as a heat source. The resulting extracts were characterized by the Folin–Ciocalteu and Ferric Reducing Antioxidant Power tests and by liquid chromatography–time-of-flight/mass spectrometry (LC–TOF/MS). The composition of the extracts under each of the optimal conditions was studied by LC–TOF/MS, and the information thus obtained compared by Venn diagrams. These diagrams, together with the extracted base peak chromatograms, were used to assess the optimal working conditions. Tentative identification of compounds was conducted using open-free databases. Grape skins from distillation industries are a source of compounds of interest for the food and nutraceutical fields. [Copyright &y& Elsevier]

Abstract: We previously reported that grape skin ethanol extract (GSE) decreases adipogenic transcription factor gene expression, inhibiting triglyceride accumulation in 3T3-L1 adipocytes. In this study, we hypothesized that GSE may induce differential expression profiles in adipocytes, thus providing protection against obesity. Thirty-five genes involved in the peroxisome proliferator-activated receptor-γ (PPARγ) signaling pathway, lipid metabolism, or adipogenesis were identified through microarray analysis of adipocytes treated with GSE. Expression of the genes involved in PPARγ signaling, Adipoq, Scd1, Nr1h3, Fabp5, Scd2, and Pparg decreased with GSE treatment, whereas expression of Ppargc1a increased. Lipid metabolism-associated genes Mlxp1, Stat5a, Hsl, Plin1, and Vdr were down-regulated. Interestingly, GSE also affected expression of genes related to the mitogen-activated protein kinases pathway. GSE extract treatment decreased expression of aP2, Fas, and Tnfa, known markers of adipogenesis, as measured by real-time polymerase reaction. These findings demonstrate the antiadipogenic effects of GSE on 3T3-L1 adipocytes at the genetic level, primarily on the PPARγ signaling pathway. [Copyright &y& Elsevier]

Abstract: Grape skin extracts from pinot noir and pinot gris exhibited significant in vitro antiviral (influenza virus) activity. Five tea infusions from grape skins (Vitis vinifera var. pinot noir and pinot gris) without any additives (control pinot noir and control pinot gris) or by adding variable amounts of green tea and hibiscus were investigated as a means to utilise wine wastes. The antioxidant activities (DPPH scavenging capacity and superoxide anion radical scavenging capacity), total phenolics, the polyphenolics profile and objective colour measurements (CIELab) were determined on freeze-dried water extracts of all five tea infusions, hibiscus and green tea. The colour parameters, L ∗ and a ∗ values, varied widely (P <0.05) for all the infusions as a result of having different levels and variety of pigments. The tea infusions exhibited weak antioxidant activity and the antiviral activity in grape skin appears not related to phenolics contents. [Copyright &y& Elsevier]

Abstract: Pressurized hot water extraction (PHWE) was employed to prepare extracts from dried grape skin of two wine grape varieties (St. Laurent and Alibernet) at various temperatures (from 40 up to 120°C) and amounts of sample (0.5, 1.0 and 1.5g). To assess the antioxidant activity of the extracts, electron paramagnetic resonance (EPR) spectroscopy was applied involving ABTS + assays. Other extract characteristics including HPLC profile of anthocyanins and total phenolic compound content were obtained as well. PHWE has also been compared with earlier results of extractions of the same grape skin samples with compressed methanol and compressed ethanol under the conditions of pressurized fluid extraction (PFE). From this comparison, PHWE emerges as the more benign and efficient extraction method to recover valuable phenolic antioxidants from grape skins for the prospective use in functional food supplements. [Copyright &y& Elsevier]

Production of silver nanoparticles (Ag-NPs) to increase photocatalytic activity of commercial TiO 2 (P25) and antibacterial activity of surgical sutures was studied. А new method of "green" synthesis of Ag-NPs from aqueous extract of grape skin (oxidation product), which is pre-processed by oxygen and ultrasound is reported. Also, a new method of electrochemical modification of surgical sutures was used. Characterization of Ag-NPs was carried out using energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM) and UV–visible spectroscopy. Zeta-potential of obtained colloidal solutions indicated the moderate stability of synthesized nanoparticles. The X-ray powder diffraction (XRD) analysis confirmed the crystallographic structure of the synthesized Ag-NPs. The component profile of grape skin extract has been analyzed using HPLC coupled to diode-array detection and tandem mass spectrometry (HPLC-DAD-MS/MS). In this study absorbable sutures were functionalized with biosynthesized AgNPs through an electrochemical and chemical deposition. Morphological analysis of Ag-NPs-coated surgical sutures was performed by SEM and Energy Dispersive X-Ray Spectroscopy (SEM-EDX) in order to evaluate the presence and distribution of silver deposited on the sutures. The sutures demonstrated bacteriostatic and antifungal effects on Gram-positive (Bacillus subtilis), Gram-negative (Escherichia coli) and Candida albicans wound pathogens. The study revealed that electrochemical deposition of Ag-NPs on nylon surgical sutures did not alter the mechanical properties of the sutures but conferred antibacterial properties. The modified TiO 2 powders with biosynthesized Ag-NPs were characterized by XRD pattern, SEM, their photocatalytic properties, and their antibacterial activities were studied. The results of the antibacterial activity studies showed that TiO 2 modified using green approach possessed higher antibacterial activity against Gram-negative bacteria in comparison with TiO 2 modified by the impregnation method. [Display omitted] • Phytochemical syntheses of Ag-NPs using grape skin extract (GSE). • To increase the reducing ability of the GSE, it was preliminarily oxidized. • The characterization of Ag-NPs was performed by UV–Vis, FTIR, and SEM. • Modified TiO 2 with Ag-NPs showed antibacterial and photocatalytic activities. • The surgical AgNP-coated sutures demonstrated bacteriostatic and antifungal effects. [ABSTRACT FROM AUTHOR]

Abstract: The tannin profiles of five grape (Vitis vinifera L.) varieties ‘Touriga Nacional’, ‘Trincadeira’, ‘Castelão’, ‘Syrah’ and ‘Cabernet Sauvignon’ and the profiles of their red monovarietal wines from their 2004 and 2005 vintages were studied. Depending on the variety, the polymeric fractions represented 77–85% in seeds and 91–99% in skins. The distribution of the mean degree of polymerisation (mDP) of the proanthocyanidins ranged from 2.8 to 12.8 for seeds and from 3.8 to 81.0 for skins. In the monovarietal wines, the distribution of the mDP of the proanthocyanidins ranged from 2.1 to 9.6. Of the total proanthocyanidins the polymeric fraction represented 77–91% in vintage 2004 and 82–95% in vintage 2005. The wine proanthocyanidins of Trincadeira and Cabernet Sauvignon showed similar tannin profiles in each vintage. After six months of storage, noticeable decreases in total proanthocyanidins concentration were measured. These were accompanied by slight decreases in prodelphinidin percentages but the percentage of galloylation and mDP remained similar. [Copyright &y& Elsevier]

Abstract: This work describes a new and innovative method for the purification of anthocyanins from grape skin extracts as liquid matrix (LM), by using carbon dioxide (CO2). The LM was obtained by extraction of anthocyanins from grape skins using a water/ethyl alcohol solution acidified with 0.2% trifluoroacetic acid (TFA). The CO2 purification process produced a desired fraction (F1) containing pure anthocyanins, and a second fraction (F2) containing ethyl alcohol and other components of the grape skins. An yield of anthocyanin of about 85%, with respect to the starting overall anthocyanin content, was obtained under the following optimized process conditions: pressure 100–130bar; temperature 30–40°C; pH of LM 2–4; percentage of ethyl alcohol in the LM 25–30%; CO2 flow rate 25–50ml/min; LM flow/CO2 flow ratio 3–10%. We have also demonstrated that the purification process allowed to eliminate ethyl alcohol from the anthocyanin extract without any thermal or chemical degradation, obtaining a high added value product which maintains its anthocyanin content and antioxidant activity unchanged. [Copyright &y& Elsevier]

Abstract: Accumulating evidence suggests that grape seed and wine polyphenol extracts possess a diverse array of actions and may be beneficial in the prevention of inflammatory-mediated disease such as cardiovascular disease and cancer. This study aimed to determine whether the reported pleiotropic effects of several polyphenolic extracts from grape seed products or red wine would also include inhibition of cholesterol uptake and cell proliferation, and inhibit a known specific target of the inflammatory process, that is, 5-lipoxygenase (5-LOX). Incubation of HT29, Caco2, HepG2, or HuTu80 cells in a medium containing [3H]cholesterol in the presence of a grape seed extract (GSE) or red wine polyphenolic compounds (RWPCs) inhibited [3H]cholesterol uptake by up to 66% (which appeared maximal). The estimated IC50 values were 60 and 83 μg/mL for RWPC and GSE, respectively. Similar cholesterol uptake inhibitory effects were observed using the fluorescent cholesterol analogue NBD cholesterol. The inhibition of cholesterol uptake was independent of the sample''s (GSE and RWPC) potent antioxidative capacity. Red wine polyphenolic compound and GSE dose dependently inhibited HT29 colon adenocarcinoma cell proliferation, which was accompanied by an increase in apoptosis. In addition, RWPC and GSE inhibited 5-LOX activity with the IC50 values being 35 and 13 μg/mL, respectively. Two of 3 other GSEs tested also significantly inhibited 5-LOX activity. Inhibition of cholesterol uptake and proinflammatory 5-LOX activity may be beneficial in preventing the development of chronic degenerative diseases such as cardiovascular disease and cancer. [Copyright &y& Elsevier]

Abstract: A fast method for the analysis of 10 of the characteristic compounds of the phenolic fraction in grape skin is proposed here. The method is based on a leaching step by superheated ethanol–water at 120°C and 80bar, which enables to maintain the leachant in liquid state and wide the range of leachable compounds (polar, mid-polar and relatively non-polar compounds) by decrease of the dielectric constant; thus, allowing high leaching efficiencies to be achieved in 30min. After leaching, the target analytes were separated by capillary electrophoresis using a 50mM sodium tetraborate with 10% methanol (pH 8.4) solution as background electrolyte. Determination was performed by simultaneous dual diode array absorption and fluorescence detection, the combination of which increased the selectivity of the overall method, particularly interesting taking into account the complexity of the leachate as no additional concentration and/or clean-up steps were required prior to electrophoretic separation, which lasted only 10min. The short time of the electrophoretic step makes it useful as a screening tool of the target analytes in commercial and non-commercial extracts belonging to the pharmaceutical, cosmetic, nutraceutical or food fields. [Copyright &y& Elsevier]

Abstract: Grape juice and skin and seed extracts of Vitis vinifera var. Ribier black table grapes were found to be highly inhibitory towards Listeria monocytogenes. This grape juice was also active against all other Listeria species tested but not against Bacillus cereus, Salmonella Menston, Escherichia coli, Staphylococcus aureus or Yersinia enterocolitica. Fractionation of the extracts showed that the antilisterial activity was strongest in the polymeric phenolic fractions. Two different types of active compounds were identified: the red-pigmented polymeric phenolics from juice and skin showed pH-dependent antilisterial activity, while the unpigmented polymeric phenolics from the seed showed antilisterial activity which was independent of pH. [Copyright &y& Elsevier]

Abstract: Pigments resulting from the direct condensation of anthocyanins and flavanols are usually associated with reactions taking place during processing and storage of plant-derived foods and beverages and have been particularly studied in aged red wines. In this paper, small amounts of flavanol–anthocyanin condensed pigments are found in different plant extracts. Structures are suggested for 10 such condensed pigments detected in extracts of strawberry, runner beans, purple corn and grape skins, based on their MS n fragmentation patterns, following analyses by electrospray tandem mass spectrometry. All of them correspond to dimers containing a flavan-3-ol [either (epi)afzelechin, (epi)catechin or (epi)gallocatechin] as the upper unit carbon–carbon linked to a lower anthocyanin unit consisting of different delphinidin, cyanidin, pelargonidin, peonidin or malvidin derivatives. The detection of these pigments in plant extracts may suggest that they are natural pigments and not products exclusively formed during storage and ageing of processed foods and beverages, as was previously assumed. [Copyright &y& Elsevier]

The vineyard produces one of the most important crops in Portugal and is affected by various pests, such as the Lobesia botrana moth, which can be attracted chemically by compounds on the grape skin.In this study, the sugar contents (glucose and fructose) on grape skin were analysed for five Portuguese Vitis vinifera grape varieties and compared in grape juice and whole grapes. Samples were harvested in July, August and September of 2001 and 2002.The quantification was attained employing a new methodology, which comprised the preparation of a methanol solution to extract the compounds from the grape skin and further chromatographic analyses by liquid chromatography (LC) with refractive index (RI) detection. The samples designated by whole grapes were homogenised, centrifuged and filtrated, while the juice was obtained by crushing and filtration.Grape skin has shown higher levels of glucose than fructose, but both compounds increased from green berry (July) to veraison (August) and had a slight decrease from veraison to harvest (September).As expected, the glucose and fructose contents (total sugar) were higher in the whole grape than in the juice and much higher than in the grape skin itself. For Loureiro and Trajadura varieties, the levels of both sugars on grape skin were very similar. This resemblance strengthened the statement of the decisive role of this parameter in female L. botrana oviposition behaviour. [Copyright &y& Elsevier]

Simulated maceration assays were carried out in wine model systems using increasing ethanol percentages from 0 to 12.5%, in order to study the extraction of flavan-3-ol monomers and oligomers from grape skins and seeds. The amount of flavan-3-ols transferred to the solutions improves with the increase in the alcohol percentage, although flavanols were much more readily released from grape skins than from seeds. Maximum release of flavanols from the skins is reached after 24 h of maceration in 12.5% ethanol, whereas long maceration and higher ethanol percentages were required for extraction from the seeds, from which maximum flavanol extraction was observed after 2–3 weeks of maceration. Thus, the length of the maceration not only had an influence in the total levels of flavanols reached in the wines, but also in their qualitative composition. The contribution of the seeds to the flavanol composition of the model wines was found to range from about 40% at 24 h of maceration in 12.5% ethanol to as high as 90% after 3 weeks. Gallocatechin was the major flavanol contributed by the skins and catechin by the seeds of the grape variety used (Vitis vinifera cv. Viura). Flavanol extraction was also followed during winemaking of commercial red wines, reaching similar conclusions to that obtained from the model assays. [Copyright &y& Elsevier]

Plant extract micronutrients are commonly added to diets for health and prevention of degenerative disease. However, there are barriers to the introduction of these products as antioxidant therapies in counteracting chronic human diseases, probably because the molecular bases of their therapeutic potential are poorly clarified. The present study was designed to evaluate the possible protective effect of combined micronutrients present in black grape skin on toxicity induced by 25–35 β-amyloid peptid or by serum of Alzheimer''s disease patients, in human umbilical vein endothelial cells (HUVECs).The hypothesis was tested by examining the results of lactic dehydrogenase (LDH) release to estimate cytoplasmic membrane breakdown; activity of mitochondrial complexes, reactive oxygen species (ROS) production and malonyl dialdehyde (MDA) levels as markers of oxidative stress induction and COMET assay to evaluate DNA fragmentation. The results demonstrate that black grape skin extract reduces the ROS production, protects the cellular membrane from oxidative damage, and consequently prevents DNA fragmentation. The experimental results suggest that this natural compound may be used to ameliorate the progression of pathology in AD disease therapy. [Copyright &y& Elsevier]

Grape products, rich in polyphenolics, inhibit platelet aggregation (PA), a risk factor for coronary artery disease. We postulated that combining extracts of grape seed (GSD) and grape skin (GSK), primary sources of grape polyphenolics, individually shown to inhibit PA, might enhance their individual antiplatelet effects. This hypothesis was examined in vitro (human platelets) and ex vivo (dog platelets) by studying the effects of the extracts on collagen-induced whole blood PA. In vitro, threshold concentration of only GSD, individually incubated with blood, significantly inhibited PA; PA was inhibited by 12.7 +/- 3.5% (P < or = 0.01). No significant changes in Pa were observed with threshold concentrations of GSK, used individually. In two dose combinations, GSD and GSK inhibited PA 40.5 +/- 10.1% (P < or = 0.005) and 96.5 +/- 3.1% (P < or = 0.001). In the ex vivo study, seven dogs were fed threshold doses of GSD or GSK individually, in combination or in combination with a proprietary enzyme blend (EB; thought to enhance bioavailability) for 8 d. PA was measured before and after each treatment. PA measurements were also repeated 24 h after the final dose of GSD + GSK + EB. Feeding the extracts individually did not affect PA, whereas feeding them in combination inhibited PA by 31.9 +/- 7.1% (P < or = 0.05). Feeding EB in addition to GSD + GSK inhibited PA by 56.2 +/- 8.1% (P < or = 0.005); 24 h later, PA was still inhibited by 31.5 +/- 10.5% (P < or = 0.05), suggesting a residual antiplatelet effect from the administration of the final dose. The results suggest that the components of GSD and GSK, when present in combination as in red wine, grape juice or in a commercial preparation containing both extracts, exhibit a greater antiplatelet effect than when present individually. [ABSTRACT FROM AUTHOR]