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Petrolina de Goiás, Brazil

Tofanelli M.B.D.,Federal University of Parana | Freitas P.L.,Federal University of Sergipe | Pereira G.E.,Embrapa Uva e Vinho Semiarido
Revista Brasileira de Fruticultura

Viticulture is an important agricultural activity in semiarid northeastern Brazil, and the quality and ease of vine propagation are very important in this context. This study evaluated the use of 2,4-dichlorophenoxyacetic acid (2,4-D) as an alternative to indolebutyric acid (IBA) in the rooting of vine rootstock cuttings. The trial was conducted at the Universidade Federal de Sergipe (São Cristóvão-SE) between January and March 2010 with cuttings of the rootstocks of ‘IAC-766’, ‘IAC-572’, and ‘Paulsen 1103’ treated with 2,4-D or IBA applied at concentrations of 0, 1000, 2000, or 3000 mg∙L-1 for 5 s and planted in a field on washed sand. At 56 days after planting, the percentages of rooted, sprouted, callused, and dead cuttings were evaluated, and also the average number and length of the rooted cuttings. The results showed that 2,4-D was not superior to IBA in the characteristics wanted for the rooting process of the vine rootstock cuttings. The vine rootstocks showed potential for propagation by cutting without auxin application. It was observed that the high concentrations were the worst for the rooting of the cuttings. © 2014 Sociedade Brasileira de Fruticultura. All rights reserved. Source

Terra M.F.,Federal University of Lavras | Prado G.,Laboratorio Of Micotoxinas | Pereira G.E.,Embrapa Uva e Vinho Semiarido | Ematne H.J.,Federal University of Lavras | Batista L.R.,Federal University of Lavras
Journal of the Science of Food and Agriculture

BACKGROUND: Ochratoxin A (OTA) is the main mycotoxin found in grapes, wines and grape juices and is considered one of the most harmful contaminants to human health. In this study, samples of tropical wines and grape juices from different grape varieties grown in Brazil were analysed for their OTA content by high-performance liquid chromatography. RESULTS: The detection and quantification limits for OTA were 0.01 and 0.03 μg L-1 respectively. OTA was detected in 13 (38.24%) of the samples analysed, with concentrations ranging from < 0.03 to 0.62 μg L-1. OTA was not detected in any of the grape juice samples. Most of the red wine samples proved to be contaminated with OTA (75%), while only one white wine sample was contaminated. However, the OTA levels detected in all samples were well below the maximum tolerable limit (2 μg L-1) in wine and grape juice established by the European Community and Brazilian legislature. CONCLUSION: The results of this study indicate a low risk of exposure to OTA by consumption of tropical wines and grape juices from Brazil. © 2012 Society of Chemical Industry. Source

Paula Barros E.,Federal University of Rio de Janeiro | Moreira N.,University of Porto | Moreira N.,Catholic University of Portugal | Elias Pereira G.,Embrapa Uva e Vinho Semiarido | And 3 more authors.

An automated headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-ion trap/mass spectrometry (GC-IT/MS) was developed in order to quantify a large number of volatile compounds in wines such as alcohols, ester, norisoprenoids and terpenes. The procedures were optimized for SPME fiber selection, pre-incubation temperature and time, extraction temperature and time, and salt addition. A central composite experimental design was used in the optimization of the extraction conditions. The volatile compounds showed optimal extraction using a DVB/CAR/PDMS fiber, incubation of 5 ml of wine with 2 g NaCl at 45 °C during 5 min, and subsequent extraction of 30 min at the same temperature. The method allowed the identification of 64 volatile compounds. Afterwards, the method was validated successfully for the most significant compounds and was applied to study the volatile composition of different white wines. © 2012 Elsevier B.V. All rights reserved. Source

De Andrade R.H.S.,Federal University of Pernambuco | De Andrade R.H.S.,Instituto Federal Of Educacao | Do Nascimento L.S.,Federal University of Pernambuco | Do Nascimento L.S.,Instituto Federal Of Educacao | And 3 more authors.
Microchemical Journal

This study determined and correlated the anthocyanin profile of Brazilian tropical (São Francisco Valley in Pernambuco), and temperate wines (Rio Grande do Sul), and temperate Chilean wines (Valle del Colchagua and Central Valley), with their geographical origins, using high performance liquid chromatography (HPLC) combined with a chemometric method, by applying Principal Component Analysis (PCA). The concentrations and the percentage of the nine anthocyanins (delphinidin-3-glucoside, cyanidin-3-glucoside, petunidin-3-glucoside, peonidin-3-glucoside, malvidin-3-glucoside, peonidin-3-glucoside-acetate, malvidin-3-glucoside-acetate, peonidin-3-glucoside coumarate and malvidin-3-glucoside coumarate) were obtained and the values varied greatly according to the cultivar, vintage and country. The results demonstrated that wines from Rio Grande do Sul showed the highest levels of anthocyanin glucosides, which served as the discrimination factor for the chemometric analysis of the samples. Wine samples from the São Francisco Valley preferentially seem to follow the biosynthetic route Naringenin. → Kaempferol → Cyanidin-3-Glucoside → Peonidin-3-Glucoside, unlike the samples from the other two regions (Chile and Rio Grande do Sul) that seem to follow the route Naringenin → Kaempferol → Delphinidin-3-Glucoside → Petunidin-3-Glucoside → Malvidin-3-Glucoside. The samples of the Syrah variety from the São Francisco Valley had higher concentrations of individual and total anthocyanins than the Chilean, suggesting the potential for successful adaptation of the cultivation of this grape to the terroir of the Brazilian northeast. © 2013 Elsevier B.V. Source

Nobrega I.C.C.,University of Pernambuco | Pereira G.E.,Embrapa Uva e Vinho Semiarido | Silva M.,Institute Tecnologia Of Pernambuco Itep | Pereira E.V.S.,University of Pernambuco | And 5 more authors.
Food Chemistry

An improved sample preparation procedure for analysis of carcinogenic ethyl carbamate (EC) in wine by GC-MS-SIM is proposed. Differences over AOAC reference procedure were: (1) use of EC-d5 as internal standard instead of less similar propyl carbamate; (2) extraction by diethyl ether instead of more toxic dichloromethane, and (3) concentration by vacuum automated parallel evaporation instead of more time and work consuming rotary evaporation. Mean recovery was 104.4%, intraday precision was 6.7% (3.4 μg L- 1) and 1.7% (88.5 μg L- 1), regression coefficient was 0.999 in the linear working range of 3-89 μg L- 1, and limits of detection and quantification were 0.4 and 1.2 μg L- 1. Applicability was demonstrated by analysis (in triplicate) of 5 wine samples. EC concentration ranged from 5.2 ± 0.2 to 29.4 ± 1.5 μg L- 1. The analytical method is selective, accurate, repeatable, linear, and has similar method performance as the reference method along with the several mentioned advantages. © 2015 Elsevier Ltd. All rights reserved. Source

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