Antiinflammatory properties of the muscadine grape (Vitis rotundifolia)

The muscadine grape possesses one of the highest antioxidant levels among fruits; yet, the effect of this fruit on mammalian metabolic systems has not received significant attention. To examine the antiinflammatory properties of the muscadine, grape skins were dried, pulverized, and extracted (10% w/v) with 50% ethanol. The extract was then tested in two different assays: the release of superoxide in phorbol myristate acetate-activated neutrophils and the release of cytokines [tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-beta), and interleukin-6 (IL-6)] by lipopolysaccharide-activated peripheral blood mononuclear cells. The release of superoxide and cytokines was inhibited by increasing concentrations of the extract. A 1:100 dilution of the extract inhibited superoxide release by approximately 60% while the release of TNF-alpha and IL-1beta was reduced at a dilution of 1:200 by approximately 15 and 90%, respectively (all P < 0.05). The inhibition pattern on the release of IL-6 was similar to that seen with TNF-alpha. In a related in vivo study, rats were fed a diet containing 5% (wt/wt) dried muscadine grape skins for 14 days and then were injected with carrageenan in the foot pad. After 3 h, paw edema was measured and the rats on the grape skin diet had approximately 50% less paw edema than controls (P < 0.05). These results demonstrate that the muscadine grape skin powder possesses significant in vitro and in vivo antiinflammatory properties.     

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。     

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.     

Polyphenol glucosylating activity in cell suspensions of grape (Vitis vinifera)

Stilbenes are phenolic molecules that have antifungal effects in the plant and antioxidant and anti-cancer effects when consumed in the human diet. Glycosylation of stilbenes increases their solubility and may make them more easily absorbed by the intestine. We have found an activity in extracts of cultured cells of Vitis vinifera (cv. Gamay Freaux) that glucosylates the stilbene resveratrol to form piceid. The Km for UDP-Glucose was 1.2 mM, and the Km for resveratrol was 0.06 mM, values similar to those of other phenolic glucosyltransferases. We investigated the resveratrol glucosylating activity of the enzyme extracted from cells grown under different light treatments (dark, visible light, light + ultraviolet (UVC) radiation) and found the activity to be unaffected or slightly reduced. In contrast, UVC light strongly stimulated extractable quercetin glucosyltransferase activity. These results, combined with analysis of phenolic compounds extracted from the differently treated cells, suggest that the resveratrol glucosyltransferase is distinct from the glucosyltransferase(s) active on other phenolics.     

Effects of water-soluble carbohydrate concentrate from Chinese jujube on different intestinal and fecal indices

This study was to investigate the effects of water-soluble carbohydrate concentrate (WSCC) prepared from Chinese jujube ( Zizyphus jujuba) on different intestinal and fecal indices in a hamster model. WSCC contained carbohydrates (771 g kg(-1) of WSCC) including glucose, fructose, pectin polysaccharide, and hemicellulose. The administration of WSCC (5.0 and 15 g kg(-1) of diet) effectively ( P<0.05) shortened gastrointestinal transit time (by 34.2-57.3%), reduced cecal ammonia (by 58.1-60.3%), elevated total short-chain fatty acid concentrations in cecum (3-4-fold), increased fecal moisture (147-170%), reduced daily fecal ammonia output (by 31.9-75.8%), and decreased the activities of beta-D-glucuronidase (by 73.0-73.8%), beta-D-glucosidase (by 58.2-85.7%), mucinase (by 46.2-72.6%), and urease (by 31.9-48.7%) in feces. This study suggested that adequate consumption of jujube WSCC (at least 5.0 g kg(-1) of diet or 40 mg day(-1)) might exert favorable effects on improving the gastrointestinal milieu and reducing the exposure of intestinal mucosa to toxic ammonia and other detrimental compounds.     

Quantitative analysis of polymeric procyanidins (Tannins) from grape (Vitis vinifera) seeds by reverse phase high-performance liquid chromatography

A reverse phase C(18) HPLC method with potential for high automated throughput has been developed for the quantitative analysis of polymeric procyanidins (tannins) in grape seed extracts. Chromatography gave rise to 13 distinct UV-absorbing peaks with good baseline separation. The UV-absorbing peak eluting last is distinct and therefore easily quantified. Biochemical analyses including ultrafiltration, protein precipitation, and Sephadex LH20 chromatography combined with electrospray mass spectrometric analyses establish that this peak predominantly contains polymeric procyanidins. The polymers, which appear to be galloylated to various degrees and seem to fragment in a characteristic manner during electrospray mass spectrometry, are well separated from catechins and procyanidin oligomers of up to 4 units. The recovery of polymeric grape seed tannins with this HPLC method was 86%, which is similar to the 89% recovery achieved with commercial quebracho tannins. The concentration of tannins in seeds from ripe Vitis vinifera cv. Shiraz grapes ranged from 1360 to 2830 mg/kg of berries.     

Physico-chemical characteristics of nanovesicle-carbohydrate complexes in grape juice concentrate

It is generally assumed that polyphenols, such as anthocyanins in fruit juice, exist in a free soluble state and are readily available for absorption in the gastro-intestinal tract. In the present study, we have investigated the interaction of polyphenols with soluble carbohydrate polymers, such as pectin and lipid nanovesicles, that are generated during homogenization of the fruit tissue during juice extraction. A commercially available grape juice concentrate contained nearly 25% of polyphenol fraction bound to macromolecules that were nondialyzable. Treatment of dialyzed juice with cellulase, pectinase, and beta-galactosidase did not cause the release of bound polyphenols; however, treatment with triton X-100 caused an increased release of bound polyphenols. The dialyzate contained relatively more -3-O glucosides and -3-O-acetoyl glucosides in comparison to the bound fraction which was enriched in -3-O-coumaroyl glucosides, suggesting qualitative differences in the bound and the free anthocyanin composition. Electron microscopic analysis of the juice fractions revealed the presence of electron-dense nanovesicle-fiber complexes ranging from 10 to 200 nm in diameter. Such complexes were absent in the dialyzate fraction. Cellulase treatment did not change the morphology of the complexes; however, treatment with pectinase and beta-galactosidase disrupted the complexes, releasing vesicular structures, suggestive of the pectin nature of the fibrous matrix. The dialyzed and the dialyzate fractions also showed differences in their 1H NMR and fluorescence spectral characteristics. The dialyzed fraction containing polyphenol-pectin complexes showed no superoxide scavenging capacity, reduced hydroxyl radical scavenging activity, and high 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, indicating potential changes in functionality because of the complex formation.     

Optimization of solid-liquid extraction of resveratrol and other phenolic compounds from milled grape canes (Vitis vinifera)

Optimization of the solid-liquid extraction conditions for trans-resveratrol, trans--viniferin, ferulic acid, and total phenolics from milled grape canes has been investigated. The temperature and ethanol concentration were found to be major process variables for all responses, whereas the solvent to solid ratio was found not to be significant for any of the responses studied. The yields of trans-resveratrol, trans--viniferin, and total phenolics increased with increasing temperature. Maximum yields of trans-resveratrol (4.25 mg/g dw), trans--viniferin (2.03 mg/g), and total phenolics (9.28 mg/g dw) were predicted from the combination of a moderate ethanol concentration (50-70%) and the highest temperature (83.6 degrees C), whereas an ethanol concentration of 35% at the lowest temperature studied (16.4 degrees C) was optimal for the extraction of ferulic acid (1.05 mg/g dw). Effective diffusivity values of resveratrol in the solid phase, D eff for different extraction conditions, were calculated by fitting the experimental results to a model derived from the Fick's second law. Effective diffusivity of resveratrol in the solid phase varied from 3.1 x 10 (-13) to 26.6 x 10 (-13) m (2) s (-1) with changing extraction conditions. The increase in effective diffusivity of resveratrol was observed with increasing temperature, and the highest predicted level was obtained when using 54% ethanol/water mixture at 83.6 degrees C. The increase in ethanol concentration exhibited the favorable effect up to 50-55%, thereafter effective diffusivity decreased with a further increase in concentration.     

Efficient one pot extraction and depolymerization of grape (Vitis vinifera) pomace procyanidins for the preparation of antioxidant thio-conjugates

Antioxidant thio-conjugates were obtained from white grape pomace by a clean and efficient one pot extraction and depolymerization method using water and cysteamine hydrochloride. To evaluate the potential of grape pomaces of different origins as sources of proanthocyanidins and conjugates, we conducted varietal comparative studies of polyphenol content, antioxidant power, and procyanidin composition. Xarel.lo proved to be the richest source of polyphenols. The total conversion into the conjugates was as high as 8 g/kg of Xarel.lo grape pomace, with a 50-fold excess of cysteamine, and 3 g/kg, with a 5-fold excess of cysteamine. After purification by preparative cation exchange and reversed phase high-performance liquid chromatography, 17 g of 63% pure 4beta-(2-aminoethylthio)epicatechin (acetate salt) was obtained from 35 kg of moist pomace. The procedure described here will make the antioxidant thio-derivatives efficiently available directly from raw plant byproducts such as grape pomace.     

Chemical characterization of red wine grape (Vitis vinifera and Vitis interspecific hybrids) and pomace phenolic extracts and their biological activity against Streptococcus mutans

Grapes are rich sources of potentially bioactive polyphenols. However, the phenolic content is variable depending on grape variety, and may be modified during vinification. In this study, we examined the chemical composition and biological activity of phenolic extracts prepared from several red wine grape varieties and their fermented byproduct of winemaking (pomace) on some of the virulence properties of Streptococcus mutans a well-known dental pathogen. Grape phenolic extracts were obtained from Vitis vinifera varieties Cabernet Franc and Pinot Noir and Vitis interspecific hybrid varieties Baco Noir and Noiret. The anthocyanins and flavan-3-ols content were highly variable depending on grape variety and type of extract (whole fruit vs fermented pomace). Nevertheless, all grape phenolic extracts remarkably inhibited glucosyltransferases B and C (70-85% inhibition) at concentrations as low as 62.5 microg/mL (P < 0.01). Furthermore, the glycolytic pH-drop by S. mutans cells was inhibited by the grape extracts without affecting the bacterial viability; an effect that can be attributed to partial inhibition of F-ATPase activity (30-65% inhibition at 125 microg/mL; P < 0.01). The biological activity of fermented pomace was either as effective as or significantly better than whole fruit grape extracts. The results showed that grape phenolic extracts, especially from pomace, are highly effective against specific virulence traits of S. mutans despite major differences in their phenolic content.     

Cytogenetic effects of grape extracts (Vitis vinifera) and polyphenols on mitomycin C-induced sister chromatid exchanges (SCEs) in human blood lymphocytes

In the present study, the effects of extracts and polyphenol-rich fractions as well as monomer polyphenols identified in them, from both red and white grapes, on mitomycin C (MMC) induced sister chromatid exchanges (SCEs) in human peripheral blood lymphocytes were investigated. The grape extracts and two of the three polyphenol-rich fractions promoted MMC-induced SCEs at concentrations from 75 to 300 microg/mL. However, none of the extracts or fractions alone induced SCEs. Thus, these results suggest caution especially with regard to the use of grape extracts as dietary supplements. On the other hand, the fact that these extracts were not genotoxic alone may indicate a selective activity against genetically damaged cells. This is the first study regarding the clastogenic effects of grape extracts in human cells. Moreover, from the tested polyphenols, caffeic acid, gallic acid, and rutin hydrate enhanced MMC-induced clastogenicity, whereas ferulic acid, protocatechuic acid, (+)-catechin, (-)-epicatechin, and trans-resveratrol had no effect at concentrations between 5 and 100 microM. The differences in the chemical structures of the tested polyphenols may account for their differential effects on MMC clastogenicity.     

Genetic fingerprinting of grape plant (Vitis vinifera) using random amplified polymorphic DNA (RAPD) analysis and dynamic size-sieving capillary electrophoresis

Dynamic size-sieving capillary electrophoresis with laser-induced fluorescence detection (DSCE-LIF) was combined with random amplified polymorphic DNA (RAPD) analysis to demonstrate the feasibility of the genetic analysis of grape plant varieties and clones within a variety. Parameters of the genomic DNA extraction process, as well as those of the RAPD analysis, were optimized specifically for this application. Polymorphic DNA fragments were generated for four different grape plant varieties including Cabernet Franc, Cabernet Sauvignon, Merlot, and Chardonnay. Relative to slab gel electrophoresis (SGE) with ethidium bromide staining, DSCE-LIF provided superior separation efficiency and detection limits in the analysis of DNA polymorphic bands. Optimal DSCE-LIF analyses were achieved using a 10-fold RAPD sample dilution, hydrodynamic sample injection, and 100 ng/mL of YO-PRO-1 DNA intercalator in the dynamic size-sieving buffer solution. In addition, the reproducibility of both the DSCE-LIF and RAPD analyses were demonstrated.     

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.     

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.     

Assessment of anthocyanins in grape (Vitis vinifera L.) berries using a noninvasive chlorophyll fluorescence method

Anthocyanins (Anths) in grape (Vitis vinifera L.) berries harvested at véraison from Pinot Noir and Pinot Meunier cultivars were assessed nondestructively by measuring chlorophyll fluorescence (ChlF) excitation spectra. With increasing Anth content, less excitation light was transmitted to the deeper Chl layers, and thus the ChlF signal decreased proportionally. By applying Beer-Lambert's law, the logarithm of the ratio between the fluorescence excitation spectra (log FER) from a green and a red berry gave the in vivo absorption spectrum of Anths, which peaked at about 540 nm. Absolute quantitative nondestructive determination of Anths for each berry was obtained by the log FER calculated for two excitation wavelengths, 540 and 635 nm (absorbed and not-absorbed by Anths, respectively) of ChlF at 685 nm. Over a range of skin colors going from green to purple, the relationship between the log [ChlF(635)/ChlF(540)] and the Anth concentration of berry extracts was fairly well fitted (r 2 = 0.92) using a power function. Reflectance spectra on the same berry samples were also measured, and Anth reflectance indices, which were originally developed for apples and table grapes, were derived. The log FER Anth index was superior to the reflectance-ratio-based index, but was as good as the color index for red grapes (CIRG) calculated from the whole visible reflectance spectrum. The proposed log FER method, applied by means of suitable portable devices, may represent a new, rapid, and noninvasive tool for the assessment of grape phenolic maturity in vineyards.     

Valorization of grape (Vitis vinifera) byproducts. Antioxidant and biological properties of polyphenolic fractions differing in procyanidin composition and flavonol content

Many byproducts and wastes generated by agroindustries contain polyphenols with potential application as food antioxidants and preventive agents against skin cancer and other diseases. The performance of polyphenolic fractions from Parellada grape (Vitis vinifera) pomace as antioxidants in different physicochemical environments was tested. Fractions containing oligomers with mean degree of polymerization between 3 and 4 and percentage galloylation ca. 30% were the most potent free radical scavengers and efficient antioxidants in an oil-in-water emulsion. A fraction including glycosylated flavonols was also efficient in the emulsion. All the fractions showed low aquatic toxicity and weak influence on proliferation of human melanoma cells.     

Determination of piceid and resveratrol in Spanish wines deriving from Monastrell (Vitis vinifera L.) grape variety

The presence of stilbenes in wine is becoming an important issue due to their claimed relation to a low incidence in coronary diseases and their increasing implication as cancer chemopreventive and neuroprotective agents. Total resveratrol content, quantified as glucoside and aglycone forms of resveratrol, has been determined in a survey of 45 Monastrell monovarietal Spanish red wine types (around 135 wine samples), belonging to Alicante and Bullas appellations. The average between ratio glucoside/aglycone forms of resveratrol in these wines was considerably high, ranging from 82 to 91% of resveratrol in its glycosidic form. This characteristic was observed in a high percentage of the studied wines, which were made under different winemaking procedures, and from different vintages (1995-2002). In addition, wines made using macerative fermentations with double amount of solid parts ("doble pasta") reached the highest levels of total stilbene content expressed as resveratrol equivalent, i.e., 30 mg/L (average of 18.8 mg/L). It can be concluded that high resveratrol glucoside concentration and low free isomer content can be considered characteristics of the Monastrell variety, as it happens to red wines deriving from other varieties grown at warm climates. This fact, also observed for other French and Portuguese red varieties, might play an important role in food habits involving these types of wines.     

Costs and benefits of wild goose conservation in Scotland

This paper applies the cost-benefit analysis framework to the issue of wild geese conservation in Scotland. Wild goose numbers have risen rapidly over the past 30 years, bringing nature conservationists into conflict with farmers whose crops are damaged. We estimate the costs of damage due to goose grazing to farmers in two goose areas, Strathbeg and Islay. Conservation benefits are estimated using a contingent valuation survey of the Scottish population, and we find that benefits outweigh costs by a very considerable margin. This can be seen as providing support for recent UK government moves to compensate farmers in goose areas in order to further conservation.     

Metabolism of fungicide diethofencarb in grape (Vitis vinifera L.): definitive identification of thiolactic acid conjugated metabolites

The metabolic fate of diethofencarb (isopropyl 3,4-diethoxycarbanilate) separately labeled with (14)C at the phenyl ring and 2-position of the isopropyl moiety was studied in grape (Vitis vinifera L.). The acetonitrile solution of (14)C-diethofencarb at a rate of 500 g a.i. ha(-)(1) was once applied topically to fruits or leaves at the maturity stage of fruits (PHI 35 days), and the plants were grown in the greenhouse until harvest. In the grape plants, diethofencarb was scarcely translocated to the untreated portion and was degraded more in the fruit as compared to the leaf. For the fruit, diethofencarb primary underwent O-deethylation at the 4-position of the phenyl ring to form the phenolic derivative, isopropyl 3-ethoxy-4-hydroxycarbanilate (0.9% of the total radioactive residue, TRR). This metabolite was successively transformed via conjugation with glucose at the phenolic hydroxy group (8.1-18.1% TRR) or with thiolactic acid at the 5-position of the phenyl ring (1.5-1.7% TRR). The thiolactic acid conjugate was further metabolized mainly to two different types of glucose conjugates at the 4-position of the phenyl ring (8.7-13.5% TRR) and the hydroxy group in the thiolactic acid moiety (6.4-7.3% TRR), as evidenced by (1)H NMR and atmospheric pressure chemical ionization-liquid chromatography-mass spectrometry together with cochromatographies with synthetic standards.     

Phenolic composition in grape (Vitis vinifera L. cv. Malbec) ripened with different solar UV-B radiation levels by capillary zone electrophoresis

The responses of Vitis vinifera L. cv. Malbec to different solar ultraviolet-B radiation (UV-B) levels were assessed in two contrasting situations, under sunlight with full UV-B (+UV-B) and filtered UV-B (-UV-B), in three different locations at 500, 1000, and 1500 m above sea level (asl). To evaluate the effects of radiation, a simple, accurate, and rapid method for the separation and simultaneous determination of representative phenolic compounds in grape berry skins by capillary zone electrophoresis was developed. Separation was carried out in less than 20 min with 20 mM sodium tetraborate buffer containing 30% methanol, pH 9.00. The procedure is fast and reliable, and extracted grape berry skins can be directly analyzed without prior sample cleanup procedure. Berry skins from the +UV-B treatment at 1500 m asl showed the highest levels of total polyphenols anthocyanins, and resveratrol, compared with the -UV-B treatment at this altitude.