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Vitis Vinifera L. (vitis + vinifera_l)
Selected AbstractsIdentification of four low molecular and water-soluble proteins from grape (Vitis vinifera L.) seedsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2010Ting Zhou Summary Profiles of soluble proteins isolated from mature seeds of grape (Vitis vinifera L.) pomace were studied using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) coupled with matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI,TOF,MS). Two-dimensional gels stained with Coomassie brilliant blue revealed more than fifty protein spots. Four abundant protein spots showing low molecular weight (Mr) and wide isoelectric point (pI) were analysed by MALDI,TOF,MS, resulting in their identification. Taken together, these results suggest that identified proteins may be linked to seed development and metabolism, but more instructive is that they have some potential functions for future food application. These results provide some insights into conversion of grape processing wastes into useful products or even as raw material for other industries. [source] A Novel Process for the Recovery of Polyphenols from Grape (Vitis vinifera L.) PomaceJOURNAL OF FOOD SCIENCE, Issue 2 2005Dietmar Kammerer ABSTRACT: A novel process for enzyme-assisted extraction of polyphenols from winery by-products was established on a pilot-plant scale. Optimization of enzymatic hydrolysis of grape skins, that is, selection of pectinolytic and cellulolytic enzymes, enzyme-substrate ratio, and time-temperature regime of enzymatic treatment, was conducted on a laboratory scale. Enzyme activities were monitored by viscosity measurement of resuspended grape pomace and by quantification of oligomeric pectin and cellulose degradation products released from cell wall material. Optimal conditions were obtained with 5000 ppm (based on dry matter) of a pectinolytic and 2500 ppm of a cellulolytic enzyme preparation, respectively, at 50°C, which were also applied in pilot-plant scale experiments. Concomitant determination of individual polyphenolics demonstrated a significantly improved yield for most compounds when compared with experiments without enzyme addition. Recovery rates were comparable to those obtained when grape pomace was extracted using sulfite. Pre-extraction of the pomace with hot water followed by treatment with cell wall degrading enzymes even increased yields of phenolic compounds. Only some quercetin glycosides and malvidin coumaroylglucoside were partly hydrolyzed due to enzyme side activities. This new process may provide a valuable alternative to the application of sulfite, which is considered crucial in food processing. [source] Study of the effect of ripening stages and climatic conditions on the physicochemical and sensorial parameters of two varieties of Vitis vinifera L. by principal component analysis: influence on enzymatic browningJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2006M Serrano-Megías Abstract The present paper describes the effects of maturation on the physicochemical, biochemical and color components of Napoleon and Dominga grape varieties, and on any differences between them. Climatic conditions were taken into account to explain the results obtained. Protein levels increased during ripening and were correlated with pH. Polyphenoloxidase activity was affected by climatic conditions (rainfall) and increased to a greater degree in Dominga than in Napoleon. Taste tests were conducted to determine the contribution of physicochemical and biochemical parameters to the sensorial properties of the grapes. Principal components analysis showed that parameters were correlated in different ways during the ripening period in Napoleon and Dominga varieties. In Dominga AE were correlated to the b parameter and in Napoleon to the L parameter. Copyright © 2005 Society of Chemical Industry [source] Abscisic acid is involved in the response of grape (Vitis vinifera L.) cv. Malbec leaf tissues to ultraviolet-B radiation by enhancing ultraviolet-absorbing compounds, antioxidant enzymes and membrane sterolsPLANT CELL & ENVIRONMENT, Issue 1 2010FEDERICO J. BERLI ABSTRACT We investigated the interactions of abscisic acid (ABA) in the responses of grape leaf tissues to contrasting ultraviolet (UV)-B treatments. One-year-old field-grown plants of Vitis vinifera L. were exposed to photosynthetically active radiation (PAR) where solar UV-B was eliminated by using polyester filters, or where PAR was supplemented with UV-B irradiation. Treatments combinations included weekly foliar sprays of ABA or a water control. The levels of UV-B absorbing flavonols, quercetin and kaempferol were significantly decreased by filtering out UV-B, while applied ABA increased their content. Concentration of two hydroxycinnamic acids, caffeic and ferulic acids, were also increased by ABA, but not affected by plus UV-B (+UV-B) treatments. Levels of carotenoids and activities of the antioxidant enzymes, catalase, ascorbate peroxidase and peroxidase were elevated by +ABA treatments, but only if +UV-B was given. Cell membrane , -sitosterol was enhanced by ABA independently of +UV-B. Changes in photoprotective compounds, antioxidant enzymatic activities and sterols were correlated with lessened membrane harm by UV-B, as assessed by ion leakage. Oxidative damage expressed as malondialdehyde content was increased under +UV-B treatments. Our results suggest that the defence system of grape leaf tissues against UV-B is activated by UV-B irradiation with ABA acting downstream in the signalling pathway. [source] Low temperature effects on photosynthesis and growth of grapevinePLANT CELL & ENVIRONMENT, Issue 7 2004L. HENDRICKSON ABSTRACT Growth and photosynthesis of grapevine (Vitis vinifera L.) planted on two sloping cool climate vineyards were measured during the early growth season. At both vineyards, a small difference in mean minimum air temperature (1,3 °C) between two microsites accumulated over time, producing differences in shoot growth rate. The growth rates of the warmer (upper) microsite were 34,63% higher than the cooler (lower) site. Photosynthesis measurements of both east and west canopy sides revealed that the difference in carbon gain between the warmer and cooler microsites was due to low temperatures restricting the photosynthetic contribution of east-facing leaves. East-facing leaves at the warmer microsite experienced less time at suboptimal temperature while being exposed to high irradiance, contributing to an average 10% greater net carbon gain compared to the east-facing leaves at the cooler microsite. This chilling-induced reduction in photosynthesis was not due to net photo-inhibition. Further analysis revealed that CO2 - and light-saturated photosynthesis of grapevines was restricted by stomatal closure from 15 to 25 °C and by a limitation of RuBP regeneration and/or end-product limitation from 5 to 15 °C. Changes in photosynthetic carboxylation efficiency implied that Rubisco activity may also play a regulatory role at all temperatures. This restriction of total photosynthetic carbon gain is proposed to be a major contributor to the temperature dependence of growth rate at both vineyards during the early season growth period. [source] Grapevine genetics after the genome sequence: Challenges and limitationsAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 2010J.M. MARTÍNEZ-ZAPATER Abstract The publication of the genome sequences of inbred grapevine plant PN40024 and the cultivar Pinot Noir has provided a new generation of molecular tools and has opened the way to functional genomics in grapevine. Establishing gene biological function is now a major challenge requiring the parallel development of molecular and genetic information. New massive pyrosequencing technologies will ensure no shortage of nucleotide sequence information. However, genetic analysis and genetic tools in grapevine still require additional development. Exploiting the existing natural genetic variation in Vitis vinifera L. and other inter-fertile Vitis species should be a priority to focus functional analyses on genes contributing to phenotypic variation because their genetic variation constitutes the basis for genetic improvement of classical cultivars and for the development of new ones. In this review, we discussed the current molecular and genetic tools available in grapevine and considered those that need to be developed to exploit natural genetic variation in the analyses of gene function. We also reviewed the scarce information on the genetic and molecular structure of relevant grapevine traits and proposed future directions. [source] A method for determination of fruit-derived ascorbic, tartaric, oxalic and malic acids, and its application to the study of ascorbic acid catabolism in grapevinesAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2009V.J. MELINO Abstract Background and Aims:, The majority of the acidity of a grapevine (Vitis vinifera L.) berry is a result of the accumulation of l -tartaric (TA) and l -malic acids (MA). TA is synthesised from l -ascorbic acid (Asc, vitamin C), the metabolism of which is poorly characterised in grapevines. In a distinct pathway, oxalic acid (OA) is also formed from Asc degradation. The aim of this study was to develop a single method whereby the distribution of Asc and its catabolites from fruit and vegetative sources could be determined. Methods and Results:, Effective recoveries of total Asc, TA, OA and MA were achieved with this extraction method, while chromatographic separation was accomplished with reversed-phase high-performance liquid chromatography (RP-HPLC). These results demonstrate that Asc and its catabolites TA and OA rapidly accumulate in immature berries, and that the Asc to dehydroascorbate ratio increases with berry maturity. Conclusions:, A method for the simultaneous analysis of Asc, TA, OA and MA in fruits is provided; moreover, we have demonstrated its use to study their distribution in fruits, rachis, leaves and roots. Significance of the Study:, This method enables accurate monitoring of the accumulation of Asc, permitting further research towards understanding acid metabolism during berry ripening. [source] Relationships between wine phenolic composition and wine sensory properties for Cabernet Sauvignon (Vitis vinifera L.)AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2008H.E. HOLT Abstract Background and Aims:, Winemakers from a commercial winery observed sensory differences in Cabernet Sauvignon wines made from three pruning treatments in a single vineyard, particularly in mouthfeel characteristics. This study examined the relationships between wine composition and wine sensory characteristics, then related these to berry weight and composition and wine quality scores. Methods and Results:, Cabernet Sauvignon from three pruning treatments , Machine, Cane and Spur , was harvested at commercial harvest date, and replicate wines were made from each for three vintages. The composition of the wines from all three pruning systems was generally similar. Differences in individual descriptive attributes did not separate the wines from the three treatments, or across vintages, despite differences in overall quality scores. Principal component analysis (PCA) could separate the wines by pruning and by vintage using wine composition or sensory parameters. Higher concentrations of anthocyanins, tannins and phenolics in berries did not always result in higher concentrations in wines. Conclusions:, In this study, higher wine tannin or wine phenolic concentrations did not result in higher wine astringency, and wine colour measures and phenolic composition were not good indicators of individual wine sensory properties or wine quality. Wine composition was not necessarily directly influenced by berry composition. Significance of the Study:, Few studies focus on the berry to wine to sensory continuum, particularly over more than one vintage or in a commercial context. This study highlighted how complex the relationships among berries, wine sensory properties and wine quality can be, particularly within a single vineyard. [source] Crop thinning (hand versus mechanical), grape maturity and anthocyanin concentration: outcomes from irrigated Cabernet Sauvignon (Vitis vinifera L.) in a warm climateAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 1 2006PAUL R. PETRIE Abstract Crop thinning subsequent to fruit set can help regulate yield and improve fruit composition at harvest. Accordingly, an experiment was established in two vineyards (Site 1 Riverland District of South Australia; Site 2 Sunraysia District of Victoria) to investigate effects of crop removal after fruit set (when berries were pea size) using a machine harvester. Specific zones of the canopy were targeted for thinning to remove a predetermined percentage of the fruit and avoid over-thinning. Cropping responses to mechanical thinning were compared with control (un-thinned) vines, and with hand thinned vines (where fruit was removed from a similar portion of the canopy as for mechanical thinning). In a fourth treatment, bunches damaged by mechanical thinning were removed by hand. Inclusion of hand thinning treatments enabled us to distinguish between the potential benefits of reduced yield and the potential damage caused by the mechanical harvester to foliage and/or remaining fruit. Both the mechanical and the hand thinning treatments reduced bunch number as well as yield by a similar amount (approximately 24% on Site 1 and approximately 45% on Site 2) and advanced fruit maturity (soluble solids accumulation at harvest), relative to un-thinned controls, by approximately 1.6 % and 1.7% respectively. Soluble solids accumulated at a similar rate for all treatments at sites, despite differences in yield, implying that the impact of thinning treatments originated prior to veraison. Berry weight was increased by hand thinning at Site1, and by all thinning treatments at Site 2. Anthocyanin concentration (berry fresh weight basis) was higher in fruit from the mechanically thinned vines compared to controls (un-thinned). Mechanical thinning successfully reduced crop level to the target yield, and improved fruit quality. Mechanical thinning, via modified use of a machine harvester, thus offers some potential to regulate yield over large and minimally pruned vineyards, in a timely and cost-effective fashion. [source] Environmental effects on cv Cabernet Sauvignon (Vitis vinifera L.) grown in Hawke's Bay, New Zealand.: 1.AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 1 2002Phenology, characterisation of viticultural environments Abstract Six Cabernet Sauvignon vineyard sites in Hawke's Bay (New Zealand), selected out of 28 sites observed in 1996/97, were studied over three consecutive seasons in order to characterise viticultural environments of this region for this cultivar. Indices of precocity of vine phenology were used to analyse the relationship between phenology at the selected sites and vegetative growth, productivity, fruit ripening and wine sensory characteristics. Marked differences in indices of precocity existed between sites. These differences were mostly correlated with vine vegetative growth and canopy indices. There was no relationship between yield and vine phenology. Indices of precocity were correlated with certain juice constituents measured on a common date, as well as the sensory scores of wines produced by microvinification from grapes harvested on different dates and maturity levels. Vineyard sites that differed in indices of precocity also differed in their environmental characteristics, particularly in soil physical properties and water balance. [source] Environmental effects on cv Cabernet Sauvignon (Vitis vinifera L.) grown in Hawke's Bay, New Zealand.: 2.AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 1 2002Development of a site index Abstract Based on observations of Cabernet Sauvignon phenology, cropping and fruit characteristics at six vineyard sites in Hawke's Bay (New Zealand) studied over three seasons, a numerical model is proposed to characterise environmental conditions of a vineyard site. The proposed model is based on air temperature in October and January, seasonal rainfall, rooting depth, gravel percentage and clay-to-silt ratio in topsoil. The ,Site Index' (SI) calculated from these variables was significantly correlated with soil temperature and volumetric soil moisture content, themselves closely linked with clay-to-silt ratio, air temperature and rainfall. Vegetative growth, canopy characteristics, precocity of veraison, total anthocyanins, TSS and malic acid concentration in grapes, as well as wine sensory score, were all significantly correlated with the SI values at six sites and over two seasons. Over the same period, correlation of SI with several viticultural variables was generally stronger than five existing climatic indices for viticulture calculated for these sites. The proposed SI index appears to have potential use for vineyard zoning and site selection and evaluation. [source] Grapevine culture in trenches: root growth and dry matter partitioningAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2001C. ZAPATA Abstract As a part of a global project aimed at comparing the physiology of several grapevine (Vitis vinifera L.) cultivars, we tested plant cultivation in trenches under semi-controlled conditions. Vegetative growth of vines of two cultivars, Pinot Noir and Merlot, from different locations, were followed during a 3-year period. Roots of trench-grown vines grew widely, leading to a root architecture closer to that observed under field conditions than that of potted vines. In addition, the root system could be sampled exhaustively for analyses. Although morphologically different, vines of the two cultivars exhibited similar patterns in dry matter production during the whole period, except at early flowering in year 3. Surprisingly, perennial parts accounted for this difference, though both cultivars were grafted onto the same SO4 rootstock clone. Consistently, vines exhibited root necrosis at any sampling date throughout spring, this process affecting more roots for the Pinot Noir/SO4 combination than for Merlot/SO4. [source] Highly Chemoselective Reduction of Aromatic Nitro Compounds to the Corresponding Hydroxylamines Catalyzed by Plant Cells from a Grape (Vitis vinifera L.).CHEMINFORM, Issue 35 2005Feng Li Abstract For Abstract see ChemInform Abstract in Full Text. [source] | ||||||||||