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PHYTOFABRICATION OF LEAD NANOPARTICLES USING GRAPE SKIN EXTRACT
Dr. K.V.PAVANI,T. SWATI,V. SNEHIKA,K. SRAVYA
International Journal of Engineering Science and Technology , 2012,
Abstract: The exploitation of various plant materials for the biosynthesis of nanoparticles is an ecofriendly and green technology. The present study reports the synthesis of lead nanoparticles using the grape skin extract. The grape skin extract induced synthesis of lead nanoparticles formation with spherical morphologies. Synthesis ofnanoparticles was assessed by UV–Vis spectroscopy. Successfully biosynthesized spherical nanoparticles with particle size range from 661nm – 796nm were characterized by scanning electron microscopy (SEM). Grape skin extract is a good source of biomaterial for the synthesis of Pb nanoparticles.
Effect of Carboxymethyl Cellulose and Alginate Coating Combined with Brewer Yeast on Postharvest Grape Preservation  [PDF]
Ren Yinzhe,Zhang Shaoying
ISRN Agronomy , 2013, DOI: 10.1155/2013/871396
Abstract: The effect of carboxymethyl cellulose and alginate coating combined with brewer yeast on postharvest grape preservation was investigated. The postharvest grapes were coated with 2% of alginate and 3% of carboxymethyl cellulose combined with ?CFU/mL of brewer yeast. The combined treatment samples showed good sensory character on day 13 compared with control samples or only coated samples. The increase of weight loss and decrease of total soluble solids of combined treatment grapes were restrained. Furthermore, the protective enzymes including superoxide dismutase, peroxidase, and catalase of combined treatment sample showed higher activities. Accordingly, the increase of malonaldehyde content was also restrained and more vitamin C was preserved in combined treatment samples. At day 13, the weight loss rate and the total soluble solids of grape treated with coating + yeast were 23.6% lower and 20.6% higher than those of control samples, respectively. Coating grapes with 2% of alginate and 3% of carboxymethyl cellulose combined with brewer yeast of ?CFU/mL was a well-proven method to preserve postharvest grapes. 1. Introduction In recent years, conventional production systems of fruits and vegetables have been characterized by an excessive use of chemical compounds during pre- and postharvest treatments. The grape is a highly perishable nonclimacteric fruit with reduced shelf-life due to decay, weight loss, and nutrient degradation during the storage time. It is traditionally treated with different chemical products such as SO2 to control the main postharvest pathogen [1]. Nevertheless, new consumer trends and subsequent legislative changes demand healthier, environmentally friendly food production systems. Edible films can be used to protect perishable food products from deterioration by retarding dehydration, providing a selective barrier to moisture, oxygen, and carbon dioxide, suppressing respiration, improving textural quality, helping to retain volatile flavor compounds, and reducing microbial growth [2]. Carboxymethyl cellulose (CMC) is the most important water-soluble cellulose derivative, with many applications in the food industry and in cosmetics, pharmaceuticals, detergents, and so forth [3]. Alginate, a polysaccharide derived from marine brown algae, has been preponderant in making edible films due to its unique colloidal properties and its ability to form strong gels or insoluble polymers upon reaction with multivalent metal cations such as calcium [4]. At present, CMC and alginate are used in fruit preservation, such as fresh garlic,
A spectrofluorimetric sensor based on grape skin tissue for determination of iron(III)
Minghui Zhang, Baozhan Zheng, Hongyan Yuan, Dan Xiao
Bulletin of the Chemical Society of Ethiopia , 2010,
Abstract: A spectrofluorimetric method based on the grape skin has been developed for the determination of Fe3+ at pH 5.0. The emission wavelength of the grape skin sensor occurs at 680 nm and the excitation wavelength at 421 nm. The fluorescence of sensor could be quenched by Fe3+ due to the complexing ability of anthocyanin with the metal ions. Anthocyanin, the main pigment in the grape skin, has been found fluorescence sensing material. The sensor based on the grape skin exhibited a calibration response for Fe3+ in two concentration ranges of 1.0 × 10-8- 1.0 × 10-5 M(r2= 0.9888) and 3.2 × 10-5- 3.2 × 10-4 (r2 = 0.9856) M at 60 oC. The detection limit was found to be 7.5×10-9M, and the other common ions did not interfere. KEY WORDS: Grape skin, Fluorescence, Iron(III) Bull. Chem. Soc. Ethiop. 2010, 24(1), 31-37.
Determination of Characteristics of Grape Berry Skin in Some Table Grape Cultivars (V. vinifera L.)  [PDF]
Demir Kok,Salih Celik
Journal of Agronomy , 2004,
Abstract: This research was carried out in nursery conditions of Tekirdag Research Institute, in Turkey in 2000 year by using of 13 table grape cultivars. Experiment was established according to randomized complete blocks design consisting of 4 replicates. In the study, weight loss in grape berry (mg berry-1), wax layers weight in grape berry skin (mg berry-1, mg cm-2, mg cm-3) and skin thicknesses of grape berry (mm) were examined according to cultivars. While the values concerning weight loss in grape berry in cultivars were differing according to measurement dates; the lowest value from wax layer weight per grape berry of cultivars was obtained from Cv. D külgen (0.004 mg berry-1) and the highest value was obtained from Cv. Alphonse Lavalleé (0.045 mg berry-1). Among the averages concerning wax layer weight per skin area of grape berry, the lowest value was 9.485 mg cm-2 for Cv. Yapincak and the highest value was 16.785 mg cm-2 for Cv. Alphonse Lavalleé. From the standpoint of wax layer weight per skin volume of grape berry, while the lowest value was obtained from cvs. Cinsaut, Karagevrek and D külgen (0 002 mg cm-3), the highest value was obtained from Cv. H nüsü (0.010 mg cm-3). Regarding skin thickness of grape berry, the lowest values were 27.50 mm for cvs. Yapincak, Razaki and Tahannebi and the highest value was 89.38 mm for Cv. Honusu.
An Examination of Chemical Composition and Molecular Properties of Grape Berry Skin Flavonoids  [PDF]
Vladimir Sadovoy, Arcadiy Silantyev, Magomed Selimov, Tatiana Shchedrina
Food and Nutrition Sciences (FNS) , 2011, DOI: 10.4236/fns.2011.210150
Abstract: Using the molecular mechanics and semi-empirical methods, this study analyzes the main characteristics of the grape skin flavonoids: resveratrol, quercetin, rutin, catechin, epicatechin gallate, and epicatechin. We have carried out a comparative analysis of the molecular properties of the flavonoids and confirmed their antioxidant properties.
A spectrofluorimetric sensor based on grape skin tissue for determination of iron(III)
Minghui Zhang,Baozhan Zheng,Hongyan Yuan,Dan Xiao
Bulletin of the Chemical Society of Ethiopia , 2010,
Abstract: A spectrofluorimetric method based on the grape skin has been developed for the determination of Fe3+ at pH 5.0. The emission wavelength of the grape skin sensor occurs at 680 nm and the excitation wavelength at 421 nm. The fluorescence of sensor could be quenched by Fe3+ due to the complexing ability of anthocyanin with the metal ions. Anthocyanin, the main pigment in the grape skin, has been found fluorescence sensing material. The sensor based on the grape skin exhibited a calibration response for Fe3+ in two concentration ranges of 1.0 × 10-8 - 1.0 × 10-5 M (r2 = 0.9888) and 3.2 × 10-5 - 3.2 × 10-4 (r2 = 0.9856) M at 60 oC. The detection limit was found to be 7.5×10-9 M, and the other common ions did not interfere.
PHENOTYPES INVESTIGATION IN THE YEAST SACCHAROMYCES CEREVISIAE ISOLATED FROM DIFFERENT GRAPE CULTIVARS FOLLOWIG FERMENTATION  [cached]
Bayraktar V.N.
Bìologì?nij Vìsnik Melìtopol?s?kogo Der?avnogo Pedagogì?nogo Universitetu ìmenì Bogdana Hmel?nic?kogo , 2012,
Abstract: Micobiological investigation was carried out on Saccharomyces cerevisiae yeast cultures, which were isolated from different varieties of vintage grape harvested from the ―Koblevo‖ winery, Nikolaev region of Ukraine. It was determined that wild yeast cultures tend to be of one of three different phenotypes. For comparison and reference, investigation of test cultures was performed with previously known phenotypes and yeast cultures Saccharomyces cerevisiae used in wine industry. It was noted that the most desirable yeast cultures had a killer phenotype. These are able to generate toxins that inhibit the growth of other yeast cultures that are present in the same substrate and compete for habitat. It was observed that yeast a neutral phenotype can also be can also utilized in wine industry biotechnology. Yeast cultures with sensitive phenotype, however, die in the substrate (grape musts) in the presence of yeast culture killer phenotypes that secrete killer toxins harmful to these sensitive phenotypes.
Proteome changes in the skin of the grape cultivar Barbera among different stages of ripening
Alfredo S Negri, Bhakti Prinsi, Mara Rossoni, Osvaldo Failla, Attilio Scienza, Maurizio Cocucci, Luca Espen
BMC Genomics , 2008, DOI: 10.1186/1471-2164-9-378
Abstract: The proteomic analysis revealed that 80 spots were differentially expressed throughout berry ripening. Applying a two-way hierarchical clustering analysis to these variations, a clear difference between the first two samplings (up to 14 days after véraison) and the following three (from 28 to 49 days after véraison) emerged, thus suggesting that the most relevant changes in protein expression occurred in the first weeks of ripening. By means of LC-ESI-MS/MS analysis, 69 proteins were characterized. Many of these variations were related to proteins involved in responses to stress (38%), glycolysis and gluconeogenesis (13%), C-compounds and carbohydrate metabolism (13%) and amino acid metabolism (10%).These results give new insights to the skin proteome evolution during ripening, thus underlining some interesting traits of this tissue. In this view, we observed the ripening-related induction of many enzymes involved in primary metabolism, including those of the last five steps of the glycolytic pathway, which had been described as down-regulated in previous studies performed on whole fruit. Moreover, these data emphasize the relevance of this tissue as a physical barrier exerting an important part in berry protection. In fact, the level of many proteins involved in (a)biotic stress responses remarkably changed through the five stages taken into consideration, thus suggesting that their expression may be developmentally regulated.Grape berry is a typical true fruit originating from the ovary and is formed by skin, flesh, seeds and a complete vascular system. They all have specific properties that are directly linked to their particular physiological roles during berry development and seed dispersal.The growth of this non-climacteric fruit is summarized by the well known double-sigmoidal curve and is divided into an initial and rapid growth, a subsequent lag phase and a second period of growth corresponding to berry ripening [1,2]. During the first phase, embryo formati
Different Anthocyanin Profiles of the Skin and the Pulp of Yan73 (Muscat Hamburg × Alicante Bouschet) Grape Berries  [PDF]
Jian-Jun He,Yan-Xia Liu,Qiu-Hong Pan,Xiang-Yun Cui,Chang-Qing Duan
Molecules , 2010, DOI: 10.3390/molecules15031141
Abstract: Yan73 is a “teinturier” red wine variety cultivated in China and used in winemaking to strengthen red wine color. Here, the anthocyanin profile in both the skin and pulp of this grape variety was analyzed by HPLC-MS. The results showed that 18 anthocyanins were detected in both the skin and the pulp, and pelargonidin-3-O-glucoside, an anthocyanin compound hardly detected in most other Vitis viniferaberries, was found. However, the contents of individual anthocyanins in the skin and the pulp were significantly different. Compared with the skin, the pulp exhibited much lower ratio of 3’,5’-substituted to 3’-substituted anthocyanins and much higher ratio of methoxylation of anthocyanin B-ring to non methoxylation, and with regard to the aromatic acylated and aliphatic acylated anthocyanins, both their contents in the skin are higher than in the pulp. The findings will provide some new insight for the tissue-specific expression and regulation of the genes involving in anthocyanin biosynthesis in grape berries.
Molecular and Technological Characterization of Saccharomyces cerevisiae Strains Isolated from Natural Fermentation of Susumaniello Grape Must in Apulia, Southern Italy  [PDF]
Mariana Tristezza,Lorenagostina Fantastico,Cosimo Vetrano,Gianluca Bleve,Daniela Corallo,Francesco Grieco,Giovanni Mita,Francesco Grieco
International Journal of Microbiology , 2014, DOI: 10.1155/2014/897428
Abstract: The characterization of autochthonous Saccharomyces cerevisiae strains is an important step towards the conservation and employment of microbial biodiversity. The utilization of selected autochthonous yeast strains would be a powerful tool to enhance the organoleptic and sensory properties of typical regional wines. In fact, indigenous yeasts are better tailored to a particular must and because of this they are able to praise the peculiarities of the derived wine. The present study described the biodiversity of indigenous S. cerevisiae strains isolated from natural must fermentations of an ancient and recently rediscovered Apulian grape cultivar, denoted as “Susumaniello.” The yeast strains denoted by the best oenological and technological features were identified and their fermentative performances were tested by either laboratory assay. Five yeast strains showed that they could be excellent candidates for the production of industrial starter cultures, since they dominated the fermentation process and produced wines characterized by peculiar oenological and organoleptic features. 1. Introduction The conversion of grape must into wine is a fermentative process performed by indigenous microorganisms, whose composition notably contributes to the sensorial and chemical properties of the wine. The main role of yeast during must fermentation is to promote the conversion of grape sugars, in particular hexoses, into ethanol, carbon dioxide, and other metabolites without the production of off-flavours. In the spontaneous grape must fermentation indigenous yeasts dynamics occurs, it being the final step always dominated by alcohol-tolerant strains [1]. The dominant yeast species is Saccharomyces cerevisiae and it was demonstrated that the fermentation process is led and completed by a limited number of strains [2]. Moreover, a sequential substitution of strains happens during must fermentation as they progress to higher ethanol concentration [3]. As the importance of S. cerevisiae role in winemaking has long been established, the use of the commercial strains of these yeast cultures in fermentation is an ordinary practice in order to ensure a reproducible product and to reduce the risk of wine spoilage. However, this custom can cause a progressive substitution of local microflora and a consequent reduction of microbial biodiversity. Indeed, knowledge of the autochthonous yeast strains will help to preserve and employ the most representative strains. The selection and the employment of autochthonous microorganisms could be a powerful instrument to improve the
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