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1.
J Food Sci Technol ; 59(12): 4673-4684, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36276533

RESUMO

Seed and peel flours of organic Bordeaux grapes (Vitis labrusca L.), containing phenolics and antioxidant capacity, influenced both the composition and properties of a yogurt. The total phenolic content (TPC) of the yogurts containing 3% of grape seed flour (GSFY) and 3% of the mixture of flours (MFY, containing 50% of seed and 50% of peel grape flours, w/w) were 18.800 ± 1.060 and 19.509 ± 1.216 mg/g of gallic acid equivalents (GAE), respectively, significantly higher than the content of the control formulation (CY, 3.199 ± 0.326 mg GAE/g). The GSFY, MFY and CY exhibited an antioxidant capacity (mean values), respectively, of 0.6100, 0.7833 and zero µmol TEAC/g by the FRAP method; and 3.6658, 2.9217 and 0.2468 µmol TEAC/g by the ABTS method. The yogurts presented typical coloration of each flour and the texture of the yogurts did not vary significantly compared to the CY. Principal Component Analysis (PCA) results distinguished the yogurts containing the grape flours and the control sample, regarding their composition and properties. The grape bioresidues were valorized by obtaining a functional and clean label yogurt.

2.
Food Chem ; 289: 714-722, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30955671

RESUMO

The objective of this study was to assess the content of bioactive compounds, organic acids and antioxidant capacity of grape juices from Isabel Precoce, BRS Carmem, BRS Cora and IAC 138-22 Máximo varieties grown on the 'IAC 766' and 'IAC 572' rootstocks under tropical conditions in Brazil. In general, the color attributes of the 'Isabel Precoce' juice were inferior to those of the other juices due to their low anthocyanin content. In contrast, 'IAC 138-22 Máximo' juices showed the highest content of most individual anthocyanins, flavonols, trans-resveratrol and total phenolic compounds, and thus, higher antioxidant capacity. Except for 'BRS Carmem', all the juices presented higher sugar accumulation when 'IAC 766' was used. This rootstock also contributed to the accumulation of t-resveratrol and most of individual anthocyanins in the 'IAC 138-22 Máximo' juices. However, the monomeric anthocyanin content was higher in 'BRS Carmem' juices when 'IAC 572' rootstock was used.


Assuntos
Antioxidantes/análise , Sucos de Frutas e Vegetais/análise , Frutas/química , Vitis/química , Antocianinas/análise , Brasil , Flavonóis/análise , Análise de Alimentos , Manipulação de Alimentos , Qualidade dos Alimentos , Polifenóis/análise , Análise de Componente Principal , Resveratrol/análise
3.
Food Chem ; 269: 157-165, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30100418

RESUMO

The phenolic profile and antioxidant activity (AOX) of "organic vs. conventional" Brazilian wines and grape juices were analyzed. A simple method for the determination of minerals Cu, Fe and Mn by F-AAS was validated and used to characterize the samples studied. In the validation of the Cu, Fe and Mn determination method, the protocol for samples preparation by hot digestion with HNO3 + H2O2 proved to be more suitable for the grape juice and wine matrices. The validation parameters were considered satisfactory. Conventional products presented higher anthocyanins content, and no significant differences were observed on other phenolic compounds, AOX and Cu, Fe and Mn minerals. All the evaluated samples presented similar results between the same cultivars and in products from grapes of the two cultivation systems. The AOX of juices and wines, organic and conventional, was high, and correlated with procyanidin B1, petunidin-3-glucoside and cyanidin-3,5-diglucoside.


Assuntos
Minerais/análise , Polifenóis/análise , Vitis/química , Vinho/análise , Antocianinas , Brasil , Cobre/análise , Frutas , Peróxido de Hidrogênio , Ferro/análise , Manganês/análise
4.
Plant Physiol Biochem ; 128: 89-98, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29772492

RESUMO

High copper (Cu) soil contents, due to the continuous vineyard application of Cu fungicides throughout the years, may impair the growth of the shoot and modify the structure of the root system. The current study aimed to investigate the threshold levels of available Cu in the soil causing toxicity effects in young grapevine plants of 'Red Niagara' cultivated in clay soils. Grapevine plantlets were cultivated in pots containing vineyard devoted soils with increasing contents of available Cu (25, 80, 100 and 165 mg kg-1), for 53 days. Photosynthesis and transpiration rates, and the quantum yield of photosystem II (Fv/Fm) were evaluated during the cultivation period. At the end of the experiment, the plant nutrient and leaf chlorophyll were determined, along with the anatomical analysis of the root system structure and plant dry matter determination. Higher levels of available Cu in the soil increased the apoplastic, symplastic and total fraction of the metal in the roots, reducing the other nutrients, especially in the shoots. Photosynthesis, transpiration rates and Fv/Fm were also reduced. Higher levels of Cu led to anatomical changes in the roots, that increased diameter, number of layers in the cortex, vascular cylinder and total root areas. It also resulted in reduced dry matter production by grapevines.


Assuntos
Cobre/metabolismo , Fazendas , Complexo de Proteína do Fotossistema II/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Solo/química , Vitis/metabolismo , Cobre/química , Transpiração Vegetal/fisiologia
5.
Food Res Int ; 107: 613-618, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29580527

RESUMO

A methodology for the rapid determination of the aromatic compounds methyl anthranilate (MA), 2'-aminoacetophenone (2-AAP) and furaneol by GC-MS was validated and used to characterize grape juice and wine elaborated with the new Brazilian grape varieties cultivated in northeastern Brazil, and Brazilian grape nectars. The method presented linearity (R2 ˃ 0.9952), good accuracy (CV < 12.9%), recovery (76.6% to 106.3%), limit of detection (23 µg L-1 to 94 µg L-1) and limit of quantification (96 µg L-1 to 277 µg L-1) acceptable in only 20 min of running. The methodology was considered satisfactory for the purpose, being a simple and rapid method for the determination of these compounds in grape derivatives drinks. In the characterization of the nectars the compound that stood out was the MA, being its presence attributed to the addition of flavorings in these products. It was evidenced a significant contribution of furaneol in the aroma of grape juice and wines elaborated with the new Brazilian grape varieties.


Assuntos
Acetofenonas/análise , Análise de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Furanos/análise , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Olfato , Vitis/química , Vinho/análise , ortoaminobenzoatos/análise , Brasil , Calibragem , Análise de Alimentos/normas , Cromatografia Gasosa-Espectrometria de Massas/normas , Limite de Detecção , Padrões de Referência , Reprodutibilidade dos Testes , Fatores de Tempo , Vitis/crescimento & desenvolvimento , Fluxo de Trabalho
6.
Molecules ; 22(11)2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29120391

RESUMO

A new resveratrol dimer (1) called labruscol, has been purified by centrifugal partition chromatography of a crude ethyl acetate stilbene extract obtained from elicited grapevine cell suspensions of Vitis labrusca L. cultured in a 14-liter stirred bioreactor. One dimensional (1D) and two dimensional (2D) nuclear magnetic resonance (NMR) analyses including ¹H, 13C, heteronuclear single-quantum correlation (HSQC), heteronuclear multiple bond correlation (HMBC), and correlation spectroscopy (COSY) as well as high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) were used to characterize this compound and to unambiguously identify it as a new stilbene dimer, though its relative stereochemistry remained unsolved. Labruscol was recovered as a pure compound (>93%) in sufficient amounts (41 mg) to allow assessment of its biological activity (cell viability, cell invasion and apoptotic activity) on two different cell lines, including one human skin melanoma cancer cell line HT-144 and a healthy human dermal fibroblast (HDF) line. This compound induced almost 100% of cell viability inhibition in the cancer line at a dose of 100 µM within 72 h of treatment. However, at all tested concentrations and treatment times, resveratrol displayed an inhibition of the cancer line viability higher than that of labruscol in the presence of fetal bovine serum. Both compounds also showed differential activities on healthy and cancer cell lines. Finally, labruscol at a concentration of 1.2 µM was shown to reduce cell invasion by 40%, although no similar activity was observed with resveratrol. The cytotoxic activity of this newly-identified dimer is discussed.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Estilbenos/química , Estilbenos/farmacologia , Apoptose , Reatores Biológicos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dimerização , Humanos , Espectroscopia de Ressonância Magnética , Melanoma , Estrutura Molecular , Células Vegetais , Resveratrol , Neoplasias Cutâneas , Estilbenos/isolamento & purificação , Vitis
7.
Front Microbiol ; 8: 532, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28424672

RESUMO

Grape must harbors a complex community of yeast species responsible for spontaneous alcoholic fermentation. Although there are detailed studies on the microbiota of Vitis vinifera L. grapes, less is known about the diversity and behavior of yeast communities present on fermenting grape must from other species of Vitis. In this work, we used a culture-dependent method to study the identity and dynamics of the indigenous yeast population present during the spontaneous fermentation of Isabella (Vitis labrusca L.) grape must. Alcoholic fermentation was conducted using standard enological practices, and the associated non-Saccharomyces and S. cerevisiae yeast community was analyzed using selective growth media and 5.8-ITS DNA sequencing. Candida californica, Candida hellenica, Starmerella bacillaris (synonym Candida zemplinina), Hanseniaspora uvarum, and Hanseniaspora vineae were the main non-Saccharomyces species identified on Isabella fermenting must. Issatchenkia hanoiensis, a yeast species rarely found on Vitis vinifera L. grapes, was also recognized on Isabella grape must. Candida azymoides, Candida californica and Pichia cecembensis, identified in this work on Isabella fermenting must, have not previously been found on Vitis vinifera L. grape must. Interestingly, C. azymoides, I. hanoiensis and P. cecembensis have recently been isolated from the surface of Vitis labrusca L. grapes from vineyards in the Azores archipelago, suggesting that specific Vitis-yeast species associations are formed independently of geographic origin. We suggest that C. azymoides, C. californica, and P. cecembensis are yeast species preferentially associated with Vitis labrusca L. grapes. Specific biological interactions between grapevines and yeast species may underlie the assembly of differential Vitis-microbial communities.

8.
Food Chem ; 228: 106-115, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28317702

RESUMO

A method for rapid determination of phenolic compounds by reversed-phase high-performance liquid chromatography (RP-HPLC), using a new column of faster resolution was validated and used to characterize commercial products produced with new grape Brazilian varieties of Northeast of Brazil. The in vitro antioxidant activity was also measured. The method showed linearity (R>0.9995), good precision (CV%<2.78), recovery (91.8-105.1%) and limits of detection (0.04-0.85mgL-1) and quantification (0.04-1.41mgL-1) according to other methods previously published with the difference of a run time of only 25min. The results obtained in the characterization of the samples differed for juices and wines from other world regions, mainly because of the high values of (-)-epigallocatechin and trans-caftaric acid. The products analyzed showed high antioxidant activity, especially the wine samples with values higher than those from wines of different regions of the world.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/química , Hidroxibenzoatos/química , Vitis/química , Vinho/análise , Antioxidantes , Brasil , Flavonoides/análise , Hidroxibenzoatos/análise , Espécies Reativas de Oxigênio
9.
Food Chem ; 188: 384-92, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26041208

RESUMO

The effect of maceration process on the profile of phenolic compounds, organic acids composition and antioxidant activity of grape juices from new varieties of Vitis labrusca L. obtained in industrial scale was investigated. The extraction process presented a high yield without pressing the grapes. The use of a commercial pectinase resulted in an increase on extraction yield and procyanidins B1 and B2 concentrations and a decrease on turbidity and concentration of catechins. The combination of 60 °C and 3.0 mL 100 kg(-1) of enzyme resulted in the highest extraction of phenolic compounds, reducing the content of acetic acid. The juices presented high antioxidant activity, related to the great concentration of malvidin, cyanidin, catechin and caffeic, cinnamic and gallic acids. Among the bioactive compounds, the juices presented high concentration of procyanidin B1, caffeic acid and trans-resveratrol, with higher levels compared to those reported in the literature.


Assuntos
Antioxidantes/análise , Manipulação de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Fenóis/análise , Vitis/química , Antocianinas/análise , Biflavonoides/análise , Ácidos Cafeicos/análise , Catequina/análise , Cinamatos/análise , Ácido Gálico/análise , Poligalacturonase/química , Análise de Componente Principal , Proantocianidinas/análise , Resveratrol , Estilbenos/análise , Temperatura
10.
Rev. ciênc. farm. básica apl ; 31(3)set.-dez. 2010.
Artigo em Português | LILACS | ID: lil-570169

RESUMO

No cenário mundial, inúmeras indústrias de cosméticos buscam a inovação, utilizando-se de matérias-primas de origens diversificadas, principalmente oriundas de vegetais, representando uma alternativa de substituição de materiais sintéticos por naturais. Com esse intuito, no presente estudo, realizou-se o desenvolvimento e a avaliação da estabilidade de emulsões e géis contendo extratos e sementes do bagaço da uva Isabel (Vitis labrusca L.), uma espécie de uva rica em compostos fenólicos e flavonoides com grande atividade antioxidante. Com isso, buscou-se evidenciar o período em que os produtos mantiveram suas propriedades físico-químicas, frente a variações climáticas forçadas em estudos acelerados, durante o período de armazenamento. Foram preparados cremes contendo 5 e 10% de extrato glicólico do bagaço da uva e géis contendo 10% de sementes trituradas, sendo acondicionados em condições ambientais distintas e avaliados, através de testes físico-químicos, no período de 60 dias. Durante esse período, não foram evidenciados sinais de instabilidade físico-química nos cremes analisados frente às condições testadas. No entanto, o gel apresentou leve alteração da cor e do odor, sugerindo a necessidade de estabilização físico-química de seus constituintes naturais com a adição de antioxidantes.


Numerous cosmetic companies around the world seek innovation, using raw materials of various origins, mainly derived from plants, as natural alternatives to synthetic materials. With this in mind, this study was carried out to develop and test the stability of emulsions and gels, respectively containing extracts of pomace and seeds of Isabel grape (Vitis labrusca L.), a fruit rich in phenolics and flavonoids, with great antioxidant activity. Thus, we sought to highlight the length of time for which the products maintained their physical and chemical properties, when subjected to forced climate variations in accelerated stability tests, during storage. Creams containing 5 and 10% glycolic extract of grape pomace and gels containing 10% powdered seeds were prepared, accommodated in various environmental conditions and assessed by physicochemical tests over 60 days. During this period, there were no signs of physicochemical instability in the creams, under the conditions tested. However, the gel was slightly altered in color and smell, suggesting a need to stabilize its natural constituents by adding antioxidants.


Assuntos
Loções de Beleza , Estabilidade de Cosméticos , Preparações de Plantas , Vitis
11.
Ciênc. agrotec., (Impr.) ; 33(3): 721-726, maio-jun. 2009. graf, tab
Artigo em Português | LILACS | ID: lil-519496

RESUMO

Os efeitos da interação entre a forma do dossel vegetativo e os fatores ambientais locais resultam no microclima que determinará alterações em alguns aspectos fisiológicos da videira, podendo afetar significativamente o crescimento vegetativo, a produtividade do vinhedo, bem como a qualidade da uva e do vinho. Objetivando-se avaliar o efeito do sistema de condução, sobre algumas características ecofisiológicas da videira (Vitis labrusca L.) foi desenvolvido experimento no Núcleo Tecnológico Epamig Uva e Vinho, na fazenda experimental "Retiro" no município de Caldas, MG, durante as safras 2003, 2004 e 2005. As variedades utilizadas no experimento foram Niágara Rosada para mesa e Folha de Figo, para produção de vinhos. Como porta - enxerto utilizou-se o "420-A". O delineamento experimental foi inteiramente casualizado, em fatorial 4x2, e os sistemas de condução adotados foram: cordão simples, latada, espaldeira e lira. Determinaram-se as seguintes variáveis: superfície foliar exposta, potencial hídrico e trocas gasosas. Verificou-se que tanto o sistema espaldeira quanto o cordão simples conferiram a menor superfície foliar exposta, em ambas as variedades e os sistemas lira e latada os maiores valores de (SFE). Verificou-se também que os sistemas cordão simples e latada conferiram os maiores valores de potencial hídrico para as duas variedades, nas diferentes fases fenológicas. Em ambas as variedades e fases fenológicas estudadas, verificou-se um comportamento semelhante entre os tratamentos em que os resultados da taxa de assimilação fotossintética das folhas, não permite evidenciar o efeito dos sistemas de condução, sobre as trocas gasosas das plantas estudadas.


The effects of the interaction between the form of the canopy and the local environmental factors result in the microclimate that will determine some physiologic aspects of the grapevine, which could significantly affect the vegetative growth of the vine, the productivity of the vineyard, as well as the quality of the grape and wine. In this context, the present work was developed in the Station of Viticulture and Enology of Caldas EPAMIG, Caldas, MG. with the aim at evaluating the effect of the conduction system on the ecophysiological characteristics of the vine (Vitis labrusca L.) during the harvest of 2003, 2004, and 2005. 'Niágara Rosada' for table and 'Leaf of Fig' were the varieties used in the experiment for the wine production and 420-A was used as the rootstock. The experimental design was the DIC in factorial 4x2. The adopted conduction systems were simple string, trellis, "espaldeira", and "lira". The following variables were determined: exposed leaf surface; water potential; and gas exchange. It was verified that both the espaldeira system as well as the simple string provided the smallest leaf surface exposed in both varieties and the systems "lira" and trellis provided the largest values of (SFE). It was also verified that the simple string and trellis systems promoted the largest values of water potential for the two varieties, in the different phenological phases studied. In both varieties and phases a similar behavior was verified among the treatments in which the results of the photosynthetic assimilation rate of the leaves does not allow evidencing the effect of the conduction systems on the gas exchange of the studied plants.

12.
Ciênc. agrotec., (Impr.) ; 32(2): 450-455, mar.-abr. 2008. graf, tab
Artigo em Português | LILACS | ID: lil-483345

RESUMO

O presente trabalho foi desenvolvido na Estação de Viticultura e Enologia da EPAMIG em Caldas-MG, e objetivou avaliar a influência do sistema de condução na produção e na qualidade dos frutos das videiras 'Folha de Figo' e 'Niagara Rosada' durante as safras 2003, 2004 e 2005. Como cultivares copa utilizou-se 'Niagara Rosada' e 'Folha de Figo', enxertadas no porta-enxerto '420-A'. O delineamento experimental foi inteiramente casualizado, em fatorial 4x2. Os sistemas de condução adotados foram cordão simples, pérgula, espaldeira e lira. Avaliaram-se as variáveis: massa e número médio de ramos; crescimento dos ramos; número de cachos; produção/planta; produtividade estimada/ha; análise química dos frutos; teor de sólidos solúveis totais (ºBrix); acidez total titulável (meq.L-1) e pH. Verificou-se que os sistemas espaldeira, lira e pérgula promoveram as maiores médias de massa e número de ramos em ambas variedades. Os sistemas de condução pérgula e cordão simples propiciaram uma certa precocidade em ambas cultivares. O porte descendente promovido pelo cordão simples induziu um menor crescimento de ramos. Os sistemas de condução foram semelhantes para a variável produção/planta para a cultivar 'Niagara Rosada' enquanto que para 'Folha de Figo' a lira foi superior. Os sistemas de condução lira e espaldeira apresentaram videiras com maiores produtividades para as cultivares estudadas. E as videiras conduzidas nos sistemas cordão simples e pérgula produzem frutos com melhor qualidade para ambas cultivares.


The present work was developed in the Station of Viticulture and Enology of Caldas EPAMIG, Caldas, MG, and it aimed to evaluate the influence of the conduction system in the production and in the quality of the fruits of the vines 'Folha de Figo' and 'Niagara Rosada' during the crops 2003, 2004 and 2005. As you cultivate cup it was used Rosy Niagara and Leaf of Fig, grafted in the door-graft ' 420-TO '. The experimental design was fully randomized, disposed in factorial scheme 4x2. The conduction systems adopted were: simple string, pergola, espaldeira and lira. The following variables were evaluated: mass and medium number of branches; shoot growth; shoot number; plant production; estimated yield; of total soluble solids levels (ºBrix), total titrable acidity (meq.L-1), and pH. It was verified that the systems espaldeira, lira and pergola promoted the highest mass averages and shoot number in both varieties. The conduction system Pergola and simple string triggered certain precocity in both varieties. The descending load promoted by the simple string induced a lower shoot growth. The conduction systems were similar for the variable production/plant for the cultivars 'Niagara Rosada,'while for 'Folha de Figo'the lira was higher. In the general, the systems of conduction lira and espaldeira showed vines with higher productivities for the analyzed cultivars. And the vines from the simple string and pergola systems produced fruits with better quality for both cultivars.

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