A detecção de resveratrol em vinhos vem sendo estudada mais intensamente nos últimos anos. O isômero trans-resveratrol tem reconhecidas atividades biológicas, e algumas delas são de uso terapêutico, tais como ação antiinflamatória, inibição da enzima lipoxigenase e ação anticarcinogênica . A presença do composto resveratrol (4,3',5'-trihidroxiestilbeno), em seus isômeros (trans e cis), foi determinada nos diferentes tipos de sucos de uva produzidos no Brasil. Além destes, também foram quantificados os polifenóis totais, acidez, açúcares redutores, sólidos solúveis e densidade, em conformidade com a legislação vigente. O resveratrol foi quantificado por cromatografia líquida de alta eficiência segundo SOUTO et al. [23], com adaptação da temperatura para 50 C. Foi detectada a presença de trans-resveratrol em todos os sucos analisados na concentração de 0,19mg.L a 0,90mg.L e o isômero cis-resveratrol foi de 0,07 a 1,59mg.L . suco de uva; cromatografia líquida de alta eficiência (CLAE); resveratrol.in vitroPalavras-chave:The resveratrol detection in wines has been studied more intensely in the last years. The isomeric trans-resveratrol has recognized biological activities, and some of them are therapeutic, such as anti-inflammatory action, enzyme lipoxigenase inhibition and anti-carcinogenic action . The presence of resveratrol (4,3',5'-trihydroxystilbene), trans and cis isomers, was investigated in industrial grape juices produced in Brazil. Additionally, total phenols, acidity, reducing sugars, soluble solids and specific gravity of samples were determined in accordance with law. Resveratrol was determined by high performance liquid chromatography by SOUTO et al. [23], adapted to the temperature of 50°C. Trans and cis-resveratrol were found in all the juices analyzed, tran-resveratrol in the concentration range of 0.19 to 0.90mg.L and cis-resveratrol in the concentration range of 0.07 to 1.59mg.L . grape juice; high performance liquid chromatography (HPLC); resveratrol.in vitroKeywords: -INTRODUÇÃOA grande procura da humanidade por meios que favoreçam uma vida saudável tem impulsionado as pesquisas por novas substâncias capazes de satisfazer tais necessidades. Entre estas substâncias encontram-se os polifenóis, destacando-se as pesquisas do resveratrol que está presente em diversas plantas, em especial na uva e seus derivados.O resveratrol é uma fitoalexina produzido por diversas plantas como Kojo-kon , Kashuwu , eucalipto, amen- (Polygunum cuspidatum) (Polygunum multiflorum)doim, amora e também está presente em uvas ( e ) [2, 8, 10, 11,12]. Na uva esta fitoalexina é sintetizada na casca como resposta ao stress causado por ataque fúngico ), dano mecânico ou por irradiação de luz ultravioleta.O resveratrol é sintetizado naturalmente na planta sob duas formas isômeras: trans-resveratrol (trans-3,5,4'-trihidroxiestilbeno) e cis-resveratrol (cis-3,5,4'-trihidroxiestilbeno),. O isômero transresveratrol é convertido para cis-resveratrol em presença da luz visível, pois esta forma é mais estável. Vitis vinifera Vitis la...

RESUMO A industrialização da batata (Solanum tuberosumL Macaca and Asterix were evaluated in Santa Maria, Rio Grande do Sul (RS)

RESUMO -O uso de indutores de resistência em plantas representa um método alternativo e promissor no controle de podridões pós-colheita de frutos. Assim sendo, foi conduzido um experimento na Universidade Tecnológica Federal do Paraná -Câmpus Dois Vizinhos -PR, no ano de 2004, com objetivo de avaliar a aplicação pré-colheita de quitosana e acibenzolar-S-metil (ASM) sobre o comportamento pós-colheita de frutos de morangueiro da cultivar Aromas. O efeito da aplicação de quitosana (0,5; 1,0 e 2,0%) e de uma dose de ASM (0,0025%) foi verificado em relação à testemunha (água destilada) e ao tratamento-controle com aplicação de fungicidas. A aplicação na pré-colheita de quitosana, nas três doses avaliadas, retardou a maturação dos frutos, manteve maior firmeza de polpa e acidez titulável e diminuiu a perda de massa. Esses tratamentos também diminuíram a produção de etileno, o teor de açúcares redutores e mantiveram mais elevado os teores de polifenóis totais. A aplicação de quitosana, nas três doses avaliadas, induziu maior resistência das plantas a patógenos, resultando na diminuição de podridão dos frutos em pós-colheita. No entanto, a concentração de 2% de quitosana causou dano aos frutos na pós-colheita, elevando a taxa respiratória e o teor de açúcares redutores. O ASM teve efeito na retenção da acidez titulável e na redução de podridões, similar ao tratamento com fungicidas. A aplicação de quitosana e ASM na pré-colheita não interferiu na qualidade organoléptica dos frutos em pós-colheita. Termos para Indexação: elicitor, ASM, quitosana, morango, qualidade, Botrytis cinerea. POST HARVEST BEHAVIOR OF STRAWBERRY FRUITS AFTER PRE HARVEST TREATMENT WITH CHITOSAN AND ACIBENZOLAR-S-METHYLABSTRACT -The use of inductors of resistance in plants represents an alternative and a promising method to control fruit rots at post harvest. The experiment was carried out at Federal Technological University of Paraná -Dois Vizinhos -Campus, during 2004 with the objective to evaluate the induction of chitosan resistance and acibenzolar-S-methyl (ASM) on strawberry plants. The treatments compared the effect of chitosan (0.5; 1.0 and 2.0%) and ASM (0.0025%) in relation to control plants (distilled water only) and those with fungicides application. The chitosan treatment in all three evaluated concentrations, delayed the fruit maturation, increased the flesh firmness and titratable acidity and decreased the mass loss. It was also observed reduction in the ethylene production and in the reduced sugars and increased the total polyphenol in strawberry fruits. The chitosan treatment in all three evaluated concentrations induced greater plant resistance to diseases with effect on the reduction of the fruit rots in the post harvest by Botrytis cindered. Although, chitosan treatment in the concentration of 2% caused damage to the fruits in the post harvest increased the respiration rate and the reduced sugar. The ASM had effect on the retention of the titratable acidity and acted efficiently on the rot reduction similar to the treatment with ...

Ultraviolet light type C (UV-C) was studied as a tool to increase enzymatic and non-enzymatic antioxidant defenses and phytochemical levels in 'Isabel' grapes (Vitis labrusca×Vitis vinifera L.). Grapes were exposed to 0, 0.5, 1.0, 2.0, or 4.0kJm UV-C and stored for 1, 3, or 5days post-treatment. One day after UV-C irradiation, the activities of grape antioxidant enzymes and thiols were increased, especially at 1.0 and 2.0kJm. These doses increased total phenolic content by almost 20%, while 0.5 and 4.0kJm had no effects. Total monomeric anthocyanin content was increased by >35% by UV-C at 1.0kJm; however, anthocyanin profile was unchanged. Grape skin antioxidant capacity was also improved by UV-C irradiation. The 1.0kJm UV-C was considered the hormetic dose. Postharvest UV-C had an elicitor effect on 'Isabel' grapes, positively impacting the antioxidant capacity and phytochemical content.

Content of exchangeable potassium (K) in t soil may influence on its content in grapevines leaves, grape yield, as well as, in must composition. The study aimed to assess the interference of exchangeable K content in the soil on its leaf content, production and must composition of 'Cabernet Sauvignon' cultivar. In September 2011, in Santana do Livramento (RS) five vineyards with increasing levels of exchangeable K in the soil were selected. In the 2012/13 and 2013/14 harvests, the grape yield, yield components, total K content in the leaves in full bloom and berries veraison were evaluated. Values of total soluble sugar (TSS), pH, total titratable acidity (TTA), total polyphenols and anthocyanins were evaluated in the must. Exchangeable K content increase in soil with sandy surface texture increased its content in leaves collected during full flowering and in berries and must pH; however, it did not affect production of the 'Cabernet Sauvignon'.

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The aim of this study was to evaluate the effect of controlled atmosphere in the change of color, chlorophyll degradation and phenolic compounds concentration in yerba maté thickly ground ("cancheada") and thinly milled ("socada"). Yerba maté samples from the towns of Arvorezinha (RS -Brazil) and São Mateus do Sul (PR -Brazil) were stored in four levels of oxygen (1, 3, 6 and 20.9kPa of O 2 ) and four levels of carbon dioxide (0, 3, 6

Few studies investigated the biological effects of American grape cultivars. We investigated the metabolic response after acute consumption of grape juice or wine from Bordo grapes (Vitis labrusca) in a placebo-controlled crossover study with fifteen healthy volunteers. Blood samples were collected 1 hour after the intake of 100 mL of water, juice, or wine to measure TBARS, ABTS, FRAP, glucose, and uric acid levels. To evaluate differences in cellular response, intracellular reactive species production (DCFH-DA) and metabolic mitochondrial viability (MTT) were assessed after exposure of human neuron-like cells (SH-SY5Y) to juice or wine. Glycemia was reduced after juice or wine consumption, whereas blood levels of uric acid were reduced after juice consumption but increased after wine consumption. Juice and wine consumption reduced plasma lipid peroxidation and increased plasma antioxidant capacity (ABTS and FRAP assays). Furthermore, juice inhibited H2O2-induced intracellular production of reactive species (RS) and increased the viability of SH-SY5Y cells. In contrast, wine (dealcoholized) exhibited a per se effect by inducing the production of RS and reducing cell viability. These results indicate a positive impact of acute consumption of Bordo juice and wine on human oxidative status, whereas only juice had protective effects against oxidative stress-induced cytotoxicity.