Search results for "grapes"
showing 10 items of 30 documents
IDENTIFICATION AND QUANTIFICATION OF PHENOLIC COMPOUNDS FROM RED GRAPE POMACE
2018
The wine industry generates a great amount of waste every year, thus its valorization is of most importance. This study uses red, fermented pomace from Cabernet Sauvignon and Feteasca Neagra cultivars. The phenolic compounds were extracted using four different extractions and the content of total polyphenols was determined using a spectrophotometrical method. Several phenolic compounds were analyzed using an HPLC method. The Cabernet Sauvignon pomace had the highest content of total polyphenols and total phenolic compounds analyzed and of quercetin, rutin, ferulic acid and resveratrol, while the Feteasca Neagra pomace had the highest content of gallic acid, syringic acid, cinamic acid and (…
From waste to health: sustainable exploitation of grape pomace seed extract to manufacture antioxidant, regenerative and prebiotic nanovesicles withi…
2020
AbstractPomace seed extract loaded vesicles were prepared as promising technological and green solution to exploit agri-food wastes and by-products, and develop high value-added products for human health. An antioxidant extract rich in bioactive compounds (epicatechins, catechin, gallic acid, quercetin and procynidins) was obtained from the seeds isolated from the pomace of Cannonau red grape cultivar. The extract was incorporated into phospholipid vesicles ad hoc formulated for intestinal delivery, by combining them, for the first time, whit a maltodextrin (Glucidex). Glucidex-transfersomes, glucidex-hyalurosomes and glucidex-hyalutransferomes were prepared, characterized and tested. Gluci…
Physico-Chemical Characterization of an Exocellular Sugars Tolerant Β-Glucosidase from Grape Metschnikowia pulcherrima Isolates
2023
A broad variety of microorganisms with useful characteristics in the field of biotechnology live on the surface of grapes; one of these microorganisms is Metschnikowia pulcherrima. This yeast secretes a β-glucosidase that can be used in fermentative processes to liberate aromatic compounds. In this work, the synthesis of an exocellular β-glucosidase has been demonstrated and the optimal conditions to maximize the enzyme’s effectiveness were determined. There was a maximum enzymatic activity at 28 °C and pH 4.5. Furthermore, the enzyme presents a great glucose and fructose tolerance, and to a lesser extent, ethanol tolerance. In addition, its activity was stimulated by ca…
Genes differentially expressed by Aspergillus carbonarius strains under ochratoxin A producing conditions
2010
Aspergillus carbonarius is an important ochratoxin A (OTA)-producing fungus that is responsible for toxin contamination of grapes and wine, coffee and cocoa. A suppression subtractive hybridization (SSH) approach was performed with two strains of A. carbonarius, antagonistic in their OTA-production ability, to identify genes whose expression is linked with the ability to produce OTA. BlastX analysis identified 109 differentially-expressed sequences putatively involved in the production of OTA, with significant similarities (Evalue < 10− 5) to sequences deposited in the NCBI non-redundant protein database. Of the 109 ESTs, 26% were involved in regulation processes, 15% corresponded to hypoth…
Le goût moisi-terreux du vin : contribution à la caractérisation cinétique et métabolique des moisissures associées à ce défaut organoleptique
2011
Some microorganisms that co-exist on the grapevine may have beneficial effects on the quality of wine whereas others may be at the origin of organoleptic deviations. In the last decade, several mouldy or earthy odors have been highlighted in various wine regions from France. (-)-geosmin was found to be the major compound responsible for this deviation, along with Botrytis cinerea and fungi belonging to the genus Penicillium, since they were frequently isolated from “earthy-musty” odor grapes. The extent of damage on the quality of wines, motivated our study on the caracterisation of grape rot fungi. First of all, the microflora of grapes from Burgundy vineyards was identified (morphological…
Simultaneous detection of the main black aspergilli responsible for ochratoxin A (OTA) contamination in grapes by multiplex real-time polymerase chai…
2009
9 pages.
EVOLUTION OF ANTHOCYANIN PROFILES FROM GRAPE TO WINE
2010
Aims: This study aimed at acquiring knowledge on the evolution of anthocyanins from grape to wine and the possibility of deducing the varietal origin of a wine from its anthocyanin profile. Methods and results: The anthocyanin “fingerprints”, or profiles, of a series of autochthonous Sicilian accessions and in the respective young wines were determined by HPLC-DAD in 2008. Data were evaluated by taking into account the development of percentages of side-ring disubstituted and trisubstituted anthocyanins, the ratio between acetylated and p-coumaroylated derivatives, and PCA results. From grape until the end of alcoholic fermentation, percentages of 3-glucosides of cyanidin, peonidin, delphin…
DETERMINATION OF THE OPTIMAL MOMENT OF HARVESTING FOR CABERNET SAUVIGNON AND MERLOT GRAPES IN DRĂGĂŞANI VINEYARD
2011
This paper presents an analysis of the main characteristics of black grapes during ripening and determining the optimum moment to harvest the grapes in the vineyard Drăgăşani. Monitoring process of maturation of the grapes has been done on the varieties of grapes for red wines Cabernet Sauvignon and Merlot from Drăgăşani vineyard.
Characterization and disruption of the cipC gene in the ochratoxigenic fungus Aspergillus carbonarius
2013
Aspergillus carbonarius is considered the most important ochratoxin A (OTA) producing fungi among those causing OTA contamination in grapes and grape-derived products. CipC is a small protein with unknown function that was previously found to be highly up-regulated in an OTA producer strain of A. carbonarius in comparison to a non OTA producer strain. In this study, cipC was characterized and disrupted via Agrobacterium tumefaciens-mediated transformation in an ochratoxigenic A. carbonarius strain in order to study whether this gene has a role in OTA production. Sequence analysis indicated that the promoter region of cipC contains putative binding sites for transcription factors that regula…
Differences in nutritional quality of parts of Vitis vinifera berries affect fitness of the European grapevine moth
2006
International audience; The European grapevine moth, Lobesia botrana (Denis & Schiffermuller) (Lepidoptera: Tortricidae), is a major grapevine pest in Europe. The larva is polyphagous and able to develop on more than 25 plant species, several of them being more suitable than Vitaceae for the fitness of L. botrana. Larvae normally eat the pulp of the berry, but may also consume the seeds according to the development stage of the berry and the larval density per bunch. Understanding the effect on individual fitness of such feeding behaviour is important to assess how suitable the different berry tissues are for this insect. We offered to the larvae either entire berries, seeds, or pulp with s…