5 resultados para Viti-vinifera wines
em CentAUR: Central Archive University of Reading - UK
Resumo:
Soil and Vitis vinifera L (coarse and fine roots, leaves, berries) concentration and geochemical partitioning of Cu, Pb and Zn were determined in a contaminated calcareous Champagne plot to assess their mobility and transfer. Accumulation ratios in roots remained low (0.1-0.4 for Cu and Zn, <0.05 for Pb). Differences between elements resulted from vegetation uptake strategy and soil partitioning. Copper, significantly associated with the oxidisable fraction (27.8%), and Zn with the acid soluble fraction (33.3%), could be mobilised by rhizosphere acidification and oxidisation, unlike Pb, essentially contained in the reducible fraction (72.4%). Roots should not be considered as a whole since the more reactive fine roots showed higher accumulation ratios than coarse ones. More sensitive response of fine roots, lack of correlation between chemical extraction results and vegetation concentrations, and very limited translocation to aerial parts showed that fine root concentrations should be used when assessing bioavailability. (C) 2008 Elsevier Ltd. All rights reserved.
Resumo:
Aims: To test the possibility that wines available in the marketplace may contain culturable yeasts and to evaluate the 5.8S-ITS rDNA sequence analysis as adequate means for the identification of isolates. Methods and Results: As a case study, typical Greek wines were surveyed. Sequence analysis of the 5.8S-ITS rDNA was tested for its robustness in species or strain identification. Sixteen isolates could be assigned into the species Brettanomyces bruxellensis, Saccharomyces cerevisiae and Rhodotorula pinicola, whereas four isolates could not be safely identified. B. bruxellensis was the dominant species present in house wines, while non-Saccharomyces sp. were viable in aged wines of high alcohol content. Conclusions: Yeast population depends on postfermentation procedures or storage conditions. Although 5.8S-ITS rDNA sequence analysis is generally a rapid method to identify wine yeast isolates at the species level, or even below that, it may not be sufficient for some genera. Significance and Impact of the Study: This is the first report to show that commercial wines may possess diverse and potentially harmful yeast populations. The knowledge of yeasts able to reside in this niche environment is essential towards integrated quality assurance programmes. For selected species, the 5.8S-ITS rDNA sequence analysis is a rapid and accurate means.
Resumo:
Sherry wine has characteristic taste and aroma, different from other wine-based alcoholic beverages. This paper reports a study of the non-volatile, low-molecular weight compounds found in sherry and related alcoholic beverages that may contribute to taste. Compounds analysed included free amino acids, organic acids, sugars and small peptides (linear and cyclic). A series of seven diketopiperazines (cyclic dipeptides) namely, cyclo(Leu-Leu), cyclo(Pro-Leu), cyclo(Pro-Ile), cyclo(Pro-Met), cyclo( Pro-Val), cyclo(Pro-Pro) and cyclo(Val-Ala) were identified for the first time in sherry. Although traces were found in some other alcoholic beverages, levels were low compared with sherry. The base wine used in the sherry production had only traces of diketopiperazines, indicating that the casking stage of sherry production might be responsible for their formation.
Resumo:
White wines are generally low in polyphenol content as compared to red wines. However, Champagne wines have been shown to contain relatively high amounts of phenolic acids that may exert protective cellular actions in vivo. In this study, we have investigated the potential neuroprotective effects of Champagne wine extracts, and individual phenolics present in these extracts, against peroxynitrite-induced injury. Organic and aqueous Champagne wine extracts exhibited potent neuroprotective activity against peroxynitrite-induced injury at low concentrations (0.1 mu g/mL). This protection appeared to be in part due to the cellular actions of individual components found in the organic extracts, notably tyrosol, caffeic acid, and gallic acid. These phenolics were observed to exert potent neuroprotection at concentrations between 0.1 and 10 mu M. Together, these data suggest that polyphenols present in Champagne wine may induce a neuroprotective effect against oxidative neuronal injury.
Resumo:
Epidemiological studies have suggested an inverse correlation between red wine consumption and the incidence of cardiovascular and neurodegenerative disorders. Although white wines are generally low in polyphenol content as compared to red wines, champagne has been shown to contain relatively high amounts of phenolic acids that may exert protective cellular actions in vivo. In this study, we have investigated the potential cardioprotective and neuroprotective effects of champagne. Our data suggest that a daily moderate consumption of champagne may improve vascular performance via the delivery of phenolic constituents capable of improving NO bioavailability and the modulation of metalloproteinase. Moreover, champagne intervention significantly increased spatial working memory in aged animals, whilst no improvement was observed in the presence of alcohol. Together, these data indicate that polyphenols present in champagne may induce cardioprotective and neuroprotective effects, delaying the onset of degenerative disorders.