Development of activated carbon using vine shoots (Vitis vinifera) and its use for wine treatment

An abundant and low-cost agricultural waste such as vine shoots (Vitis vinifera) (VS), which is generated by the annual pruning of vineyards, has been used as raw material in the preparation of powder activated carbon (AC) with a view to develop a new fining agent for white wines. A commercial activated carbon, S5X-Agrovin, was used for comparison purposes. From VS size-reduced pieces, AC was prepared using phosphoric acid as activating agent. The concentration of the H(3)PO(4) solution, the impregnation temperature, and the carbonization conditions were controlled. The carbons were texturally characterized by gas adsorption (N(2), -196 degrees C), mercury porosimetry, and density measurements. FT-IR spectroscopy was used in the analysis of the surface functional groups and structures of the carbons. Three varieties of white wine (i.e., cv. Cayetana, cv. Macabeo, and cv. Sauvignon Blanc) were treated with the activated carbons. Color changes were monitored by UV-vis spectrometry. Significant differences in the degree of uptake of polyphenols were observed depending on the wine variety and on the method of preparation of activated carbon. The carbon prepared by first impregnation of VS with the 60 vol% H(3)PO(4) solution at 50 degrees C and by then carbonization of the resultant product at 400 degrees C for 2 h presents a higher ability to discolor the white wines. The action of this carbon is comparable to that shown by the commercial product. Both carbons possess a well-developed porosity in the macropore range.     

Light dependent proton excretion by roots of entire vine plants (Vitis vinifera L.)

Protons released into distilled water by roots of entire vine plants (Vitis vinifera) were measured by an automatic titration device. Excretion rates were about 500 to 1000 μmol H⁺/12h/plant showing that H⁺ excretion was independent of ion uptake. Proton excretion in the light was significantly higher (p < 5 %) than H⁺ excretion in the dark. The Fe-chlorosis resistant cultivar “Faber” excreted more than twice as much H⁺ per plant as compared with the Fe-chlorosis sensitive cultivar “Huxel” (p < 5 %). There was no great difference in H⁺ excretion per unit root weight, between the two cultivars. It is suggested that the ability of vine plants to excrete H⁺ is related to their susceptibility to Fe-chlorosis. Protons excreted by roots may neutralize the HCO₃^? in the rhizosphere. Bicarbonate is assumed to induce Fe-chlorosis.     

Survey of grapevine Vitis vinifera stem polyphenols by liquid chromatography-diode array detection-tandem mass spectrometry

Grapes and red wine prepared from Vitis vinifera L. contain a variety of polyphenols. Some information is available about the polyphenols of the seeds and leaves of grapevine, but considerably less is known about the polyphenols of woody stems. In this paper, we describe the results of a study of polyphenolic compounds in grapevine stems. We demonstrate how a combination of reversed phase high-performance liquid chromatography with ultraviolet-diode array detection and electrospray ionization-tandem mass spectrometry ion-trap detection enables characterization of a phytochemical mixture of considerable complexity. As the polyphenol source, the stems of three frost-hardy grapevine varieties [Hasaine (Hasansky) sladki, Zilga, and Yubilei Novgoroda] were used. The main group of methanol-extractable polyphenols of stems consists of trans-resveratrol and its derivatives including oligomers and glucosides. As minor components of the extract, stilbenoid piceatannol as well as a number of nonstilbenoid polyphenols, mostly flavan-3-ols and phenolic acids glucosides, were determined. The total polyphenol content of the grapevine stems depends on the variety, whereby the stems of cultivar Yubilei Novgoroda with white grapes contain significantly less of both groups of polyphenols.     

Influence of vine vigor on grape (Vitis vinifera L. Cv. Pinot Noir) and wine proanthocyanidins

The relationships between variations in grapevine (Vitis vinifera L. cv. Pinot noir) growth and resulting fruit and wine phenolic composition were investigated. The study was conducted in a commercial vineyard consisting of the same clone, rootstock, age, and vineyard management practices. The experimental design involved monitoring soil, vine growth, yield components, and fruit composition (soluble solids, flavan-3-ol monomers, proanthocyanidins, and pigmented polymers) on a georeferenced grid pattern to assess patterns in growth and development. Vine vigor parameters (trunk cross-sectional area, average shoot length, and leaf chlorophyll) were used to delineate zones within both blocks to produce research wines to investigate the vine-fruit-wine continuum. There was no significant influence of vine vigor on the amount of proanthocyanidin per seed and only minimal differences in seed proanthocyanidin composition. However, significant increases were found in skin proanthocyanidin (mg/berry), proportion of (-)-epigallocatechin, average molecular mass of proanthocyanidins, and pigmented polymer content in fruit from zones with a reduction in vine vigor. In the wines produced from low-vigor zones, there was a large increase in the proportion of skin tannin extracted into the wine, whereas little change occurred in seed proanthocyanidin extraction. The level of pigmented polymers and proanthocyanidin molecular mass were higher in wines made from low-vigor fruit compared to wines made from high-vigor fruit, whereas the flavan-3-ol monomer concentration was lower.     

Evaluation of the composition of vine shoots and oak chips for oenological purposes by superheated liquid extraction and high-resolution liquid chromatography-time-of-flight/mass spectrometry analysis

Vine shoots are characterized in this research and compared to oak chips, frequently employed in the aging of wine or spirits. For this purpose, liquid chromatography-diode array detection and liquid chromatography-time-of-flight/mass spectrometry (LC-TOF/MS) analyses of hydroalcoholic extracts from vine shoots pertaining to 18 different vine varieties and from five varieties of oak chips have been carried out. The concentrations of a representative panel of interesting compounds from an oenological point of view have been compared in the extracts, finding similarity patterns for many of them. The analysis by LC-TOF/MS in high accuracy mode has led to the identification of numerous compounds in the hydroalcoholic extracts. The statistical analysis has enabled identification of the vine-shoot varieties providing extracts with more similar composition to that given by extracts from oak chips. Therefore, these vine-shoots varieties are suitable to be presented as an alternative to the use of oak barrels or oak chips in the aging process of wine and spirits.     

Effects of vine or bunch shading on the glycosylated flavor precursors in grapes of Vitis vinifera L. Cv. syrah

Effects of the modification of vine or bunch environment on glycoconjugates were studied in Syrah berries over two years. Vines were shaded from berry set to maturity, with black polyethylene nets of different mesh size to obtain 30 and 50% of the direct sunlight. Bunches were naturally shaded by the leaves or artificially with 90% shade bags. Sun-exposed berries were chosen as control berries. A quantitative decrease in levels of glycoconjugates was observed in shaded bunches, particularly for phenolic and C(13)-norisoprenoidic glycosides. In the same way, vine shading caused a decrease in the contents of glycosides of terpenols, phenols, and C(13)-norisoprenoids in berries, but the grape environment (microclimate) affected the berry composition more than the vine environment. A cluster thinning experiment confirmed the independence of grapes with regard to the plant for the biosynthesis of the C(13)-norisoprenoid glycosides.     

Influence of vine training and sunlight exposure on the 3-alkyl-2-methoxypyrazines content in musts and wines from the Vitis vinifera variety cabernet sauvignon

The influence of vine training and sunlight exposure on the 3-alkyl-2-methoxypyrazines contents in musts and wines was studied by means of two previously reported methods based on headspace solid-phase micro-extraction. Experimental samples were monitored throughout grape ripening and wine making. 3-Isobutyl-2-methoxypyrazine, 3-sec-butyl-2-methoxypyrazine and 3-isopropyl-2-methoxypyrazine were identified. The 3-isobutyl-2-methoxypyrazine content decreased throughout grape ripening in all of the sample types studied. After 1 day of maceration with the skins, there was an increase, but after racking, no further increase was observed. No significant differences between samples were found during grape ripening. Wines from goblet-trained vines, however, contained significantly less 3-isobutyl-2-methoxypyrazine. Clusters protected from sunlight since the beginning of the veraison resulted in wines with a significantly lower content of this compound than the control samples.     

Solar UV-B and ABA are involved in phenol metabolism of Vitis vinifera L. increasing biosynthesis of berry skin polyphenols

It has been previously found that abscisic acid (ABA) participates in the activation of grapevine leaf tissue defense against potentially damaging effects of solar ultraviolet-B radiation (UV-B), apparently by triggering biosynthesis of phenols that filter the harmful radiation and act as antioxidants. The present work studies the effect of solar UV-B and exogenously applied ABA on berry growth, sugar accumulation, and phenol (anthocyanin and nonanthocyanin) profiles across berry development and ripening of Vitis vinifera L. cv. Malbec in a vineyard at 1450 m of altitude. The grapevines were exposed to relatively high UV-B irradiation (normal sunlight; +UV-B) and also to a reduced UV-B treatment (filter exclusion; -UV-B). These two UV-B treatments were combined with weekly spray applications to the leaves and berries of 1 mM ABA (+ABA) or H(2)O (-ABA). Reduction of UV-B delayed berry development and maturation, whereas the +UV-B and +ABA combined treatment hastened berry sugar and phenol accumulation. +UV-B/+ABA treatments also reduced berry growth and decreased sugar per berry without affecting sugar concentration (°Brix) at harvest. Berry skin ABA levels were higher in the +UV-B and +ABA combined treatment, which also hastened the onset of ripening up to 20 days. Berry skin ABA levels then decreased toward harvest, implying a possible role for ABA in the control of ripening in this nonclimacteric fruit. Under both +UV-B and +ABA treatments berry skin phenols were additively increased with a change in anthocyanin and nonanthocyanin profiles and increases in the proportion of phenols with high antioxidant capacity.     

Procyanidins from Vitis vinifera seeds: in vivo effects on oxidative stress

The purpose of this study was to evaluate the effect of supplementation with procyanidins from Vitis vinifera on markers of oxidative stress. Ten healthy volunteers received a daily dose of 110 mg of procyanidins for 30 days. Fasting venous blood samples were taken before and at the end of the supplementation period and after 7 days of wash-out. The total antioxidant activity and the plasma concentrations of alpha-tocopherol were not modified. Conversely, the levels of alpha-tocopherol in red blood cell membranes increased significantly from 1.8 +/- 0.1 to 2.8 +/- 0.2 mg/g. Similarly, the lymphocyte oxidized DNA [8-oxo-7,8-dihydro-2'-deoxyguanosine/2'-deoxyguanosine ratio] was reduced from 7.23 +/- 2.47 to 2.34 +/- 0.51, and the red blood cell membrane fatty acid composition shifted to a higher level of polyunsaturated fatty acids. On the basis of these results, it may be suggested that dietary procyanidins exert their antioxidant protection in vivo by sparing liposoluble vitamin E and reducing DNA oxidative damage.     

Analysis of grape Vitis vinifera L. DNA in must mixtures and experimental mixed wines using microsatellite markers

Because wine quality highly relies on the varietal composition of the must, the development of methods allowing the authentication of varieties in musts and wines would be of great value as a guarantee of quality. Microsatellite markers have already been applied to the authentication of grape juices (Faria, M. A.; Magalh?es, R.; Ferreira, M. A.; Meredith, C. P.; Ferreira Monteiro, F. J. Agric. Food Chem. 2000, 48, 1096-1100) and to the analysis of experimental wines (Siret, R.; Boursiquot, J. M.; Merle, M. H.; Cabanis, J. C.; This, P. J. Agric Food Chem. 2000, 48, 5035-5040). In the present paper, we accessed the usefulness of this technology for the analysis of must and wine mixtures. The detection limit of DNA mixtures was first estimated on DNA extracted from leaves: 4% of a foreign DNA can be detected. Analysis of must and wine mixtures (Chardonnay B/Clairette B and Syrah N/Grenache N) was performed on experimental fermentations. DNA was extracted along the fermentation process and analyzed using five microsatellite loci. The 70:30 (v/v) mixtures were successfully analyzed until the end of the fermentation. The applications of these results to commercial purposes are discussed.     

New phenolic grape skin products from Vitis vinifera cv. Pinot Noir

Anthocyanins and their related compounds were extracted from grape skins of Pinot noir, using 50% aqueous methanol, and purified by solid phase extraction chromatography using XAD-7 resin to obtain a pigment-rich fraction. This fraction was subjected to multilayer coil countercurrent chromatography (MLCCC) using a quaternary solvent system consisting of tert-butyl methyl ether/n-butanol/acetonitrile/water acidified with 0.01% trifluoroacetic acid (2:2:0.1-1.8:5) (v/v/v/v) in a step gradient elution to separate anthocyanin oligomers from grape anthocyanins. In the process of the characterization of the MLCCC fractions by electrospray mass spectrometry, two noncolored anthocyanin derivatives were found and characterized on the basis of their mass spectral data. As a result, these compounds have been tentatively identified as coupling products between both hydrated malvidin-3-glucoside and peonidin-3-glucoside, with 2-S-glutathionyl caffeoyl tartaric acid (GRP). It is therefore proposed that grape skins contain this new class of coupling product, and a possible chemical pathway for their formation is suggested.     

Isolation of isolectins from Vitis vinifera L. Cv. Chardonnay grape berries

A lectin fraction from Chardonnay grape juice has been isolated by affinity chromatography on a column of p-aminophenyl beta-D-glucoside-derivatized agarose. The lectin fractions agglutinate rabbit and human erythrocytes without serological specificity. None of the usual monosaccharides, glycosides, or glycoproteins inhibit the hemagglutinating activity. Erythroagglutination is only inhibited by nitrophenyl glycosides, p-nitrophenyl beta-D-glucoside being the strongest inhibitor. In SDS-PAGE in the presence of 2-mercaptoethanol and gel filtration HPLC, the lectin fraction gave a single band or peak corresponding to M(r) 13.2-11.9 kDa, thus indicating it to be a monomer. Three bands were observed by isoelectric focusing with pI values of 4.1, 4. 4, and 4.9. The isolectins seem to be glycoproteins since they are bound on a concanavalin A-Sepharose column.     

Identification of table grape cultivars (Vitis vinifera L.) by the isoenzymes from the woody stems

Results from the identification of a collection of 43 table grape (Vitis vinifera L.) cultivars by isoenzymes from woody stems are presented. Plant extracts were separated by polyacrylamide gel electrophoresis. Isoenzyme analysis was carried out for peroxidases, catechol oxidase, glutamate oxalacetate transaminase, superoxide dismutase, esterases, and acid phosphatase. The last two systems were not adequate, while the rest showed a more or less marked polymorphism. Catechol oxidase was the system with the highest level of polymorphism. The combination of the zymograms allowed the separation of 31 out of the 43 studied cultivars. The other 12 cultivars were separated in five groups. The use of this methodology for differentiation of grapevine cultivars is recommended.     

Effects of copper exposure in tissue cultured Vitis vinifera.

The present study determined the effects of copper treatment on some biochemical parameters in a closed system. Sauvignon grapevines were cultured in agar and exposed to copper levels ranging from 0.07 to 10 microg Cu/g medium. Chlorophylls, carotenoids, lipids, sucrose, soluble sugars, starch, cellulose, and minerals in root, leaves, and sap were determined. Copper levels over 5 microg Cu/g inhibit root and plantlet development. Copper-exposed plants have higher levels of chlorophylls and carotenoids as well as total lipids. Soluble sugars decrease without changes in starch or sucrose. Copper concentration increases dramatically in roots and leaves. Iron concentrations are lower in leaves, although they increase in roots, with respect to control plants. Sap flow and translocation of essential elements are reduced. Reduction of K translocation can be related to limited use of water by the plant and, thus, reduction in growth and physiological activity.     

Antioxidant activities of grape (Vitis vinifera) pomace extracts

Antioxidant-rich fractions were extracted from grape (Vitis vinifera) pomace using ethyl acetate, methanol, and water. The extracts were screened for their potential as antioxidants in different models. The ethyl acetate, methanol, and water extracts showed 76, 87.1, and 21.7% antioxidant activities at 100 ppm, respectively, using the 1,1-diphenyl-2-picrylhydrazyl model system. As the methanol extract of grape pomace showed maximum antioxidant activity among all of the extracts, it was selected to determine its effect on lipid peroxidation, hydroxyl radical scavenging activity, and human low-density lipoprotein (LDL) oxidation. The methanol extract showed 71.7, 73.6, and 91.2% inhibition using the thiobarbituric acid method, hydroxyl radical scavenging activity, and LDL oxidation, respectively, at 200 ppm. Treatment of albino rats of the Wistar strain with a single dose of CCl(4) at 1.25 mL/kg of body weight decreases the activities of catalase, superoxide dismutase (SOD), and peroxidase by 81, 49, and 89%, respectively, whereas the lipid peroxidation value increased nearly 3-fold. Pretreatment of the rats with the methanolic extract of grape pomace at 50 mg/kg (in terms of catechin equivalents) followed by CCl(4) treatment causes restoration of catalase, SOD, and peroxidase by 43.6, 73.2, and 54%, respectively, as compared with control, whereas lipid peroxidation was restored to values comparable with the control. Histopathological studies of the liver of different groups also support the protective effects exhibited by the methanol extract of grape pomace by restoring the normal hepatic architecture. Owing to this property, the studies on grape pomace can be further extended to exploit its possible application for the preservation of food products as well as a health supplement and neutraceutical.     

Aroma composition of Vitis vinifera Cv. tannat: the typical red wine from Uruguay

The free volatiles, as well as those released from the glycosidically bound forms by enzyme hydrolysis, have been analyzed to chracterize young Tannat wines from two successive vintages. The Tannat wine showed some aroma profile peculiarities detected in the free forms but, above all, in the bound fraction for the level and profile of the norisoprenoidic fraction. Among the free volatile compunds, a rather low content of C(6) alcohols with a prevalence of cis-3-hexen-1-ol on the trans form and sometimes a remarkable level of trans-2-hexen-1-ol seem to be typical for the variety. C(13)-norisoprenoidic and monoterpenic volatiles made up approximately 42% of the total level of the volatiles observed in the glycosidase enzyme-released fraction. The other volatiles were C(6) alcohols (6%) and benzenoid compounds (51%). The dominating monoterpene alcohols were the cis and trans isomers of 3,7-dimethyl-1,6-octadiene-3,8-diol (8-hydroxylinalool). The C(13)-norisoprenoid pattern was composed by 3-hydroxy-beta-damascone, 3-oxo-alpha-ionol, vomifoliol, 4-oxo-beta-ionol, 3-oxo-7,8-dihydro-alpha-ionol, 4-oxo-7,8-dihydro-beta-ionol, grasshopper ketone, and 7,8-dihydrovomifoliol.     

Polyphenol screening of pomace from red and white grape varieties (Vitis vinifera L.) by HPLC-DAD-MS/MS

Phenolic compounds of 14 pomace samples originating from red and white winemaking were characterized by HPLC-MS. Up to 13 anthocyanins, 11 hydroxybenzoic and hydroxycinnamic acids, and 13 catechins and flavonols as well as 2 stilbenes were identified and quantified in the skins and seeds by HPLC-DAD. Large variabilities comprising all individual phenolic compounds were observed, depending on cultivar and vintage. Grape skins proved to be rich sources of anthocyanins, hydroxycinnamic acids, flavanols, and flavonol glycosides, whereas flavanols were mainly present in the seeds. However, besides the lack of anthocyanins in white grape pomace, no principal differences between red and white grape varieties were observed. This is the first study presenting comprehensive data on the contents of individual phenolic compounds comprising all polyphenolic subclasses of grapes including a comparison of several red and white pomaces from nine cultivars. The results obtained in the present study confirm that both skins and seeds of most grape cultivars constitute a promising source of polyphenolics.     

葡萄籽中水溶性钙结合蛋白的分离和鉴定

为了开发植物源葡萄籽补钙制剂,该研究通过亚细胞定位试验表明,葡萄籽的胚乳中含有大量的钙元素。通过电泳分析发现,葡萄籽的水溶性蛋白包括2种主要成分,其中一种是11 S球蛋白(蛋白质B),也是最主要的钙结合蛋白,另一种是表观分子量为670 k Da的蛋白质A。在蛋白质组成相同的情况下,用传统的碱溶酸沉法来分离葡萄籽蛋白会导致大量的钙流失。但用30%~50%硫酸铵沉淀法得到的蛋白质得率是(22.5±0.02)g/kg,蛋白质中钙质量分数(3.47%)是碱溶酸沉法(1.11%)的3倍。该研究结果为食品工业中矿物结合蛋白质的分离纯化提供参考。     

Influence of vine vigor on grape (Vitis vinifera L. Cv. Pinot Noir) anthocyanins. 1. Anthocyanin concentration and composition in fruit

The relationships between grapevine (Vitis vinifera) vigor variation and resulting fruit anthocyanin accumulation and composition were investigated. The study was conducted in a commercial vineyard consisting of the same clone, rootstock, age, and vineyard management practices. The experimental design involved assigning vigor zones in two vineyard sites based upon differences in vine growth. Fruits and wines were analyzed by HPLC from designated vigor zones in 2003 and 2004. Average berry weight (grams), average dry skin weight (milligrams), degrees Brix, and pH were higher and titratable acidity (grams per liter) was lower in 2003 compared to 2004. In 2003, only the highest and lowest vigor zones had differences in berry weight, whereas there were no differences in 2004. In both years, high vigor zones had lower degrees Brix and higher titratable acidity (milligrams per liter). Accumulation of anthocyanins (milligrams per berry) was greater in 2003 compared to 2004. There was a trend for lower anthocyanin concentration (milligrams per berry) in high vigor zones in both years. In 2004 compared to 2003, there was a higher proportion of malvidin-3-O-glucoside and lower proportions of the other four anthocyanins (delphinidin-, cyanidin-, petunidin-, and peonidin-3-O-glucosides) found in Pinot Noir. In both years, site A had proportionally higher peonidin-3-O-glucoside and lower malvidin-3-O-glucoside than site B. Some of these differences may be related to the higher exposure and temperatures found in site B compared to site A and also in the low vigor zones.     

Influence of vine vigor on grape (Vitis vinifera L. Cv. Pinot Noir) anthocyanins. 2. Anthocyanins and pigmented polymers in wine

The relationships between grapevine (Vitis vinifera) vigor variation and resulting wine anthocyanin concentration and composition and pigmented polymer formation were investigated. The study was conducted in a commercial vineyard consisting of the same clone, rootstock, age, and vineyard management practices. Vine vigor parameters were used to designate vigor zones within two vineyard sites (A and B) to produce research wines (2003 and 2004) and conduct a model extraction experiment (2004 only) to investigate the vine-fruit-wine continuum. Wines and model extracts were analyzed by HPLC and UV-vis spectrophotometry. For the model extractions, there were no differences between sites for pomace weight, whereas juice volume was higher for site A. This was not related to a larger berry size. Site A had a higher anthocyanin concentration (milligrams per liter) in the model extracts than site B specifically for the medium- and low-vigor zones. For anthocyanin composition in the model extraction, site B had a greater proportion of malvidin-3-O-glucoside and less of the remaining anthocyanin glucosides (delphinidin, cyanidin, petunidin, and peonidin) compared to site A. In the wines, there was a vintage effect, with the 2003 wines having a higher anthocyanin concentration (milligrams per liter) than the 2004 wines. This appears to have been primarily due to a greater accumulation of anthocyanins in the fruit. In general, the medium-vigor zone wines had higher anthocyanin concentrations than either the high- or low-vigor zone wines. There was also vintage variation related to anthocyanin composition, with the 2003 wines having a higher proportion of delphinidin and petunidin glucosides and lower malvidin-3-O-glucoside compared to 2004. In both years, there were higher proportions of delphinidin and petunidin glucosides in wines made from low-vigor-zone fruit. Wines made from low-vigor zones showed a greater propensity to form vitisin A as well as pigmented polymers. Low-vigor-zone wines had a approximately 2-fold increase in pigmented polymer concentration (milligrams per liter) over high-vigor-zones wines. There was a strong positive relationship between pigmented polymer concentration, bisulfite bleaching resistant pigments, proanthocyanidin concentration, and color density in wines. Overall, differences found in the wines magnified variation in the fruit.