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1.
J Sci Food Agric ; 103(4): 1821-1831, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36377405

RESUMO

BACKGROUND: Pruned vine shoots prepared as toasted fragments (SEGs) have recently been proposed as enological additives capable of producing differentiated quality wines. In this work, the composition of phenolic and volatile compounds of SEGs, before and after contact with wines, has been studied. RESULTS: SEGs from Tempranillo and Cabernet Sauvignon were used, which were kept in contact for 30 days with red wines made with the same varieties. Phenolic compounds were the ones with the highest sorption in SEGs, but a variety-dependent behavior was observed in anthocyanins and flavonols, with an increase in some malvidin derivatives only in Tempranillo wine and an increase in (-)-epicatechin in SEGs and Cabernet Sauvignon wine. trans-Resveratrol was transferred from SEGs to wine but also increased in SEGs regardless of the variety used. The volatile compounds that were most retained in SEGs were phenylethyl alcohol and ethyl lactate, but in lower proportions than the phenolic compounds and without important changes in wines. CONCLUSION: The high content of phenolic compounds in SEGs after their use as enological additives suggests that they could be considered as a source of anthocyanins and as raw materials for phenolic compounds with recognized antioxidant properties. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Antocianinas , Vitis , Antocianinas/química , Fenóis/química , Resveratrol , Antioxidantes , Flavonóis/química , Vitis/química
2.
Molecules ; 26(6)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33802807

RESUMO

Infertility is a potential side effect of radiotherapy and significantly affects the quality of life for adolescent cancer survivors. Very few studies have addressed in pubertal models the mechanistic events that could be targeted to provide protection from gonadotoxicity and data on potential radioprotective treatments in this peculiar period of life are elusive. In this study, we utilized an in vitro model of the mouse pubertal testis to investigate the efficacy of crocetin to counteract ionizing radiation (IR)-induced injury and potential underlying mechanisms. Present experiments provide evidence that exposure of testis fragments from pubertal mice to 2 Gy X-rays induced extensive structural and cellular damage associated with overexpression of PARP1, PCNA, SOD2 and HuR and decreased levels of SIRT1 and catalase. A twenty-four hr exposure to 50 µM crocetin pre- and post-IR significantly reduced testis injury and modulated the response to DNA damage and oxidative stress. Nevertheless, crocetin treatment did not counteract the radiation-induced changes in the expression of SIRT1, p62 and LC3II. These results increase the knowledge of mechanisms underlying radiation damage in pubertal testis and establish the use of crocetin as a fertoprotective agent against IR deleterious effects in pubertal period.


Assuntos
Carotenoides/farmacologia , Fertilidade/efeitos dos fármacos , Puberdade/efeitos dos fármacos , Lesões por Radiação/tratamento farmacológico , Testículo/efeitos dos fármacos , Vitamina A/análogos & derivados , Animais , Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Carotenoides/uso terapêutico , Catalase/metabolismo , Células Cultivadas , Regulação para Baixo , Proteína Semelhante a ELAV 1/metabolismo , Fertilidade/efeitos da radiação , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos da radiação , Imuno-Histoquímica , Técnicas In Vitro , Masculino , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Poli(ADP-Ribose) Polimerase-1/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Puberdade/efeitos da radiação , Túbulos Seminíferos/citologia , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/efeitos da radiação , Sirtuína 1/metabolismo , Superóxido Dismutase/metabolismo , Testículo/efeitos da radiação , Regulação para Cima , Vitamina A/farmacologia , Vitamina A/uso terapêutico , Raios X
3.
Membranes (Basel) ; 10(7)2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-32660066

RESUMO

The effectiveness of a preparative integrated ultrafiltration/solid-phase extraction (UF/SPE) process for purification of oligomeric procyanidins (OPCs) from a crude grape seed extract (GSE) was studied for the first time. The separation of OPCs from polymeric procyanidins (PPCs) by UF was very efficient. The membrane showed an acceptable filtration flux of 6 to 3.5 L/h·m2 at 0.5 bar of transmembrane pressure and 95% recovery of its water flux after chemical cleaning. The process was scalable to a pilot scale. The separation of very polar and ionic species from OPCs by SPE (XAD7HP and XAD16 resins) was also very good, but both adsorbents lost their retention capacities quickly, due probably to irreversible retention of OPCs/PPCs. Even though the global purification of OPCs by the integrated UF/SPE process allowed the recovery of 24.2 g of highly purified OPCs (83% purity) from 14.4 L of crude grape seed extract, the use of these adsorbents for further purification of the OPCs was very limited.

4.
Cardiol J ; 27(5): 489-496, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32589258

RESUMO

BACKGROUND: Despite being associated with worse prognosis in patients with COVID-19, systematic determination of myocardial injury is not recommended. The aim of the study was to study the effect of myocardial injury assessment on risk stratification of COVID-19 patients. METHODS: Seven hundred seven consecutive adult patients admitted to a large tertiary hospital with confirmed COVID-19 were included. Demographic data, comorbidities, laboratory results and clinical outcomes were recorded. Charlson comorbidity index (CCI) was calculated in order to quantify the degree of comorbidities. Independent association of cardiac troponin I (cTnI) increase with outcomes was evaluated by multivariate regression analyses and area under curve. In addition, propensity-score matching was performed to assemble a cohort of patients with similar baseline characteristics. RESULTS: In the matched cohort (mean age 66.76 ± 15.7 years, 37.3% females), cTnI increase above the upper limit was present in 20.9% of the population and was associated with worse clinical outcomes, including all-cause mortality within 30 days (45.1% vs. 23.2%; p = 0.005). The addition of cTnI to a multivariate prediction model showed a significant improvement in the area under the time-dependent receiver operating characteristic curve (0.775 vs. 0.756, DC-statistic = 0.019; 95% confidence interval 0.001-0.037). Use of renin-angiotensin-aldosterone system inhibitors was not associated with mortality after adjusting by baseline risk factors. CONCLUSIONS: Myocardial injury is independently associated with adverse outcomes irrespective of baseline comorbidities and its addition to multivariate regression models significantly improves their performance in predicting mortality. The determination of myocardial injury biomarkers on hospital admission and its combination with CCI can classify patients in three risk groups (high, intermediate and low) with a clearly distinct 30-day mortality.


Assuntos
Betacoronavirus , Cardiomiopatias/mortalidade , Cardiomiopatias/virologia , Infecções por Coronavirus/complicações , Infecções por Coronavirus/mortalidade , Pneumonia Viral/complicações , Pneumonia Viral/mortalidade , Idoso , COVID-19 , Cardiomiopatias/diagnóstico , Infecções por Coronavirus/terapia , Cuidados Críticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/terapia , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Taxa de Sobrevida , Troponina I/sangue
5.
Int J Mol Sci ; 21(2)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936544

RESUMO

Over recent years, many authors discussed the effects of different natural compounds on glioblastoma (GBM). Due to its capacity to impair survival and progression of different cancer types, saffron extract (SE), named crocetin (CCT), is particularly noteworthy. In this work, we elucidated the antitumor properties of crocetin in glioma in vivo and in vitro models for the first time. The in vitro results showed that the four tumor cell lines observed in this study (U251, U87, U138, and U373), which were treated with increasing doses of crocetin, showed antiproliferative and pro-differentiative effects as demonstrated by a significant reduction in the number of viable cells, deep changes in cell morphology, and the modulation of mesenchymal and neuronal markers. Indeed, crocetin decreased the expression of Cluster of Differentiation CD44, CD90, CXCR4, and OCT3/4 mesenchymal markers, but increased the expression of ßIII-Tubulin and neurofilaments (NFH) neuronal linage-related markers. Epigenetic mechanisms may modulate these changes, since Histone Deacetylase, HDAC1 and HDAC3 were downmodulated in U251 and U87 cells, whereas HDAC1 expression was downmodulated in U138 and U373 cells. Western blotting analyses of Fatty Acid Synthase, FASN, and CD44 resulted in effective inhibition of these markers after CCT treatment, which was associated with important activation of the apoptosis program and reduced glioma cell movement and wound repair. The in vivo studies aligned with the results obtained in vitro. Indeed, crocetin was demonstrated to inhibit the growth of U251 and U87 cells that were subcutaneously injected into animal models. In particular, the Tumor To Progression or TTP values and Kaplan-Meier curves indicated that crocetin had more major effects than radiotherapy alone, but similar effects to temozolomide (TMZ). An intra-brain cell inoculation of a small number of luciferase-transfected U251 cells provided a model that was able to recapitulate recurrence after surgical tumor removal. The results obtained from the orthotopic intra-brain model indicated that CCT treatment increased the disease-free survival (DFS) and overall survival (OS) rates, inducing a delay in appearance of a detectable bioluminescent lesion. CCT showed greater efficacy than Radio Therapy (RT) but comparable efficacy to temozolomide in xenograft models. Therefore, we aimed to continue the study of crocetin's effects in glioma disease, focusing our attention on the radiosensitizing properties of the natural compound and highlighting the ways in which this was realized.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Carotenoides/isolamento & purificação , Carotenoides/uso terapêutico , Crocus/química , Glioblastoma/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Carotenoides/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Intervalo Livre de Doença , Ácido Graxo Sintases/metabolismo , Feminino , Humanos , Receptores de Hialuronatos/metabolismo , Injeções Subcutâneas , Estimativa de Kaplan-Meier , Medições Luminescentes , Mesoderma/patologia , Camundongos Nus , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Vitamina A/análogos & derivados
6.
Oxid Med Cell Longev ; 2017: 8928604, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29270246

RESUMO

Cancer therapies are associated with increased infertility risk due to accelerated reproductive aging. Oxidative stress (OS) is a potential mechanism behind ovarian toxicity by cyclophosphamide (CPM), the most ovotoxic anticancer drug. An important sensor of OS is SIRT1, a NAD+-dependent deacetylase which regulates cellular defence and cell fate. This study investigated whether the natural carotenoid crocetin and the synthetic compound AS101 protect the ovary against CPM by modulating SIRT1 and mitochondrial markers. We found that the number of primordial follicles of female CD1 mice receiving crocetin plus CPM increased when compared with CPM alone and similar to AS101, whose protective effects are known. SIRT1 increased in CPM mouse ovaries revealing the occurrence of OS. Similarly, mitochondrial SIRT3 rose, whilst SOD2 and the mitochondrial biogenesis activator PGC1-α decreased, suggesting the occurrence of mitochondrial damage. Crocetin and AS101 administration prevented SIRT1 burst suggesting that preservation of redox balance can help the ovary to counteract ovarian damage by CPM. Decreased SIRT3 and increased SOD2 and PGC1-α in mice receiving crocetin or AS101 prior to CPM provide evidence for mitochondrial protection. Present results improve the knowledge of ovarian damage by CPM and may help to develop interventions for preserving fertility in cancer patients.


Assuntos
Carotenoides/uso terapêutico , Ciclofosfamida/efeitos adversos , Mitocôndrias/metabolismo , Ovário/efeitos dos fármacos , Sirtuína 1/metabolismo , Telúrio/uso terapêutico , Animais , Feminino , Humanos , Camundongos , Ovário/metabolismo , Vitamina A/análogos & derivados
7.
Molecules ; 20(9): 17570-84, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26402666

RESUMO

BACKGROUND: Endothelial dysfunction, characterized by an enhancement in vasoconstriction, is clearly associated with hypertension. Saffron (Crocus sativus L.) bioactive compounds have been recognized to have hypotensive properties. Recently, we have reported that crocetin exhibits potent vasodilator effects on isolated aortic rings from hypertensive rats. In this work, we have aimed to analyze the anticontractile ability of crocetin or crocetin esters pool (crocins) isolated from saffron. Thus, we have studied the effects of saffron carotenoids on endothelium-dependent and -independent regulation of smooth muscle contractility in genetic hypertension. METHODS: We have measured the isometric responses of aortic segments with or without endothelium obtained from spontaneously hypertensive rats. The effects of carotenoids were studied by assessing the endothelial modulation of phenylephrine-induced contractions (10(-9)-10(-5) M) in the presence or absence of crocetin or crocins. The role of nitric oxide and prostanoids was analyzed by performing the experiments with L-NAME (NG-nitro-l-arginine methyl ester) or indomethacin (both 10(-5) M), respectively. RESULTS: Crocetin, and to a minor extent crocins, diminished the maximum contractility of phenylephrine in intact rings, while crocins, but not crocetin, increased this contractility in de-endothelizated vessels. In the intact vessels, the effect of crocetin on contractility was unaffected by indomethacin but was abolished by L-NAME. However, crocetin but not crocins, lowered the already increased contractility caused by L-NAME. CONCLUSIONS: Saffron compounds, but especially crocetin have endothelium-dependent prorelaxing actions. Crocins have procontractile actions that take place via smooth muscle cell mechanisms. These results suggest that crocetin and crocins activate different mechanisms involved in the vasoconstriction pathway in hypertension.


Assuntos
Carotenoides/farmacologia , Crocus/química , Hipertensão/tratamento farmacológico , Músculo Liso Vascular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Aorta/efeitos dos fármacos , Carotenoides/química , Modelos Animais de Doenças , Ésteres/química , Ésteres/farmacologia , Hipertensão/fisiopatologia , Masculino , Extratos Vegetais/química , Ratos , Ratos Endogâmicos SHR , Vitamina A/análogos & derivados
8.
J Vasc Res ; 51(5): 393-404, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25531977

RESUMO

BACKGROUND: Hypertension is associated with endothelial dysfunction characterized by decreased vasorelaxation. Crocetin, a bioactive compound of saffron, exhibits favorable cardiovascular properties. We analyze the vasomodulatory effects of crocetin in hypertension. METHODS: Myographical experiments were performed to compare the relaxation induced by acetylcholine (ACH) on aortic rings from normotensive (Wistar) and hypertensive (SHR) rats, incubated with or without crocetin or saffron extract and L-NAME or indomethacin. Extracts were also assayed in deendothelialized rings. UV-vis spectrophotometry and HPLC-DAD were used to characterize and quantify the saffron used. RESULTS: Crocetin enhanced the ACH relaxations in aorta from hypertensive (strongly) and normotensive rats (weakly). Saffron extract did not modify this. Crocetin plus L-NAME abolished the relaxant response in SHR but not in Wistar aorta. Crocetin plus indomethacin did not modify the indomethacin response in either SHR or Wistar aorta. Crocetin in rubbed segments did not modify the ACH responses. In contrast, saffron increased this response in rubbed segments from SHR but not Wistar rats. CONCLUSION: Crocetin exerts healthy vasomodulatory effects in hypertension, strongly improving endothelium-dependent ACH relaxations via endothelial nitric oxide but not the cyclooxygenase pathway. This work proposes that crocetin supplements are a possible complement in the therapy of hypertension.


Assuntos
Acetilcolina/farmacologia , Anti-Hipertensivos/farmacologia , Carotenoides/farmacologia , Crocus/química , Hipertensão/tratamento farmacológico , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Animais , Anti-Hipertensivos/isolamento & purificação , Carotenoides/isolamento & purificação , Inibidores de Ciclo-Oxigenase/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Hipertensão/genética , Hipertensão/fisiopatologia , Masculino , Miografia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Fitoterapia , Plantas Medicinais , Ratos Endogâmicos SHR , Ratos Wistar , Vasodilatadores/isolamento & purificação , Vitamina A/análogos & derivados
9.
Food Chem ; 136(1): 224-36, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23017417

RESUMO

Different dehydrated waste grape skins from the juice industry were added into aged and young red wines as an innovative way of compensating for colour loss before bottling. After addition of grape skins, colour intensity of wines increased a mean 11% and a maximum of 31% with predominance of the red component. Total polyphenols mean increase was 10% with a maximum value of 20%. Analysis of low molecular weight phenolic compounds by HPLC-DAD showed a significant (p<0.05) content increase of the bioactive compounds gallic acid, (+)-catechin, (-)-epicatechin, and (E)-resveratrol. Anthocyanins content also increased at an average of 50mg/l. The volatile profile of wines analysed by SBSE-GC-MS was only moderately influenced by the treatments. Mixtures of dehydrated waste grape skins were useful to improve the colour and polyphenol profile of red wines, considering them a useful tool for correcting colour loss before bottling.


Assuntos
Fenóis/análise , Vitis/química , Compostos Orgânicos Voláteis/análise , Vinho/análise , Biotecnologia , Catequina/análise , Cor , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Resveratrol , Estilbenos/análise
10.
J Food Prot ; 72(10): 2217-20, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19833050

RESUMO

A microbiological study of saffron spice was undertaken in the context of a European research project (Methodologies for Implementing International Standards for Saffron Purity and Quality, the acronym for which is SAFFIC), analyzing 79 samples obtained from the main producer countries, namely Greece, Iran, Italy, Morocco, and Spain. Current microbiological quality criteria are the same as for other spices, but saffron is added in minute quantities during the cooking process, so the health risk associated with microbial contamination might be lower. We did not detect Salmonella either by culture or by PCR methods in any sample, and Escherichia coli was only found in five samples. Enterobacteriaceae were frequently found (70.9% of the samples), but most of them belonged to species of probable environmental origin. Aerobic sporulated bacteria were also common, but only three samples contained Bacillus cereus at low levels (<200 CFU g(-1)). Clostridium perfringens counts were also very low, with only one sample reaching >100 CFU g(-1), an acceptable value. Overall, microbial contamination in saffron was markedly lower than it was in other spices.


Assuntos
Qualidade de Produtos para o Consumidor , Crocus/microbiologia , Contaminação de Alimentos/análise , Controle de Qualidade , Clostridium perfringens/isolamento & purificação , Contagem de Colônia Microbiana , Enterobacteriaceae/isolamento & purificação , Escherichia coli/isolamento & purificação , Manipulação de Alimentos/métodos , Humanos , Salmonella/isolamento & purificação
11.
Molecules ; 14(3): 1160-70, 2009 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-19325516

RESUMO

The effect of parabens on the shelf-life of crocetin esters and picrocrocin in aqueous saffron solutions was studied. Degradation of saffron crocetin esters fits a first-order kinetics model, and the results indicated that the crocetin (beta-D-glucosyl)-(beta-D-gentiobiosyl) esters were more stable than the crocetin di-(beta-D-gentiobiosyl) esters regardless of whether trans and cis isomers were considered. Under all tested conditions both parabens gave good results, especially propyl paraben that showed a greater influence on the degradation rate constant, except for cis-crocetin di-(beta-D-gentiobiosyl) ester and cis-crocetin (beta-D-glucosyl)-(beta-D-gentiobiosyl) ester. In presence of propyl paraben (200 mg/L), the half-life periods of trans-crocetin di-(beta-D-gentiobiosyl) esterimproved considerably, up to four-fold. Special attention has been paid to the effect of propyl paraben on 46 saffrons with different crocetin ester contents. No differences were observed in terms of picrocrocin. By analysis of variance, it is noteworthy that there were differences between the mean content of crocetin esters for all analysed saffron, except for trans-crocetin (beta-D-glucosyl)-(beta-D-gentiobiosyl) ester.


Assuntos
Carotenoides , Crocus/química , Cicloexenos , Conservantes de Alimentos , Glucosídeos , Parabenos/farmacologia , Terpenos , Ésteres , Meia-Vida , Cinética , Extratos Vegetais , Conservantes Farmacêuticos , Vitamina A/análogos & derivados , Água
12.
J Agric Food Chem ; 54(3): 973-9, 2006 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-16448211

RESUMO

Crocetin esters present in saffron (Crocus sativus L.) stigmas and in Gardenia jasminoides Ellis fruit are the compounds responsible for their color. Of the fifteen crocetin esters identified in this study, five new compounds were tentatively identified: trans and cis isomers of crocetin (beta-D-triglucoside)-(beta-D-gentibiosyl) ester, trans and cis isomers of crocetin (beta-D-neapolitanose)-(beta-D-glucosyl) ester, and cis crocetin (beta-D-neapolitanose)-(beta-D-gentibiosyl) ester. The most relevant differences between both species were a low content of the trans crocetin (beta-D-glucosyl)-(beta-D-gentibiosyl) ester, the absence of trans crocetin di-(beta-D-glucosyl) ester in gardenia, and its higher content of trans crocetin (beta-D-gentibiosyl) ester and cis crocetin di-(beta-D-gentibiosyl) ester. With the same chromatographic method it was possible to identify, in a single run, ten glycosidic compounds in saffron extracts with a UV/vis pattern similar to that of picrocrocin; among them, 5-hydroxy-7,7-dimethyl-4,5,6,7-tetrahydro-3H-isobenzofuranone 5-O-beta-D-gentibioside and 4-hydroxymethyl-3,5,5-trimethyl-cyclohexen-2-one 4-O-beta-D-gentibioside were tentatively identified for the first time in saffron. Of these ten glycosides, only the O-beta-D-gentibiosyl ester of 2-methyl-6-oxo-2,4-hepta-2,4-dienoic acid was found in gardenia samples, but it was possible to identify the iridoid glycoside, geniposide.


Assuntos
Carotenoides/análise , Crocus/química , Ésteres/análise , Gardenia/química , Glucosídeos/análise , Terpenos/análise , Cromatografia Líquida , Cicloexenos , Flores/química , Frutas/química , Glicosídeos/análise , Iridoides/análise , Piranos/análise , Espectrometria de Massas por Ionização por Electrospray , Vitamina A/análogos & derivados
13.
J Agric Food Chem ; 53(19): 7609-16, 2005 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-16159193

RESUMO

The red grapes co-winemaking effect on phenolic fraction and wine color has been studied for the first time, where Monastrell was comacerated and cofermentated with Cabernet Sauvignon and Merlot. Changes in the relative abundance of anthocyanins were observed as well as hyperchromic shifts at 530 and 620 nm; these effects remain constant after aging. Co-winemaking also favored copigmentation, giving way to more stable anthocyanins and facilitating their polymerization. With regard to color evolution, the mixture of Monastrell with Merlot grapes was more appropriate than with Cabernet Sauvignon for aging wines in oak barrels. The extent of copigmentation was more important in young wines than in aged wines. This is mainly due to the self-anthocyanin monomer reactions in the case of young wines, whereas in aged wines copigmentation is mainly due to the reaction between the anthocyanins and other polyphenolic cofactors. Discriminant analysis showed the possibility of differentiating wines according to the aging time and the type of wine, with color parameters (color intensity, OD 620 nm, and OD 520 nm) being the most important discrimination variables in the first case and petunidin-3-glucoside and peonidin-3-glucoside contents in the second case.


Assuntos
Cor , Flavonoides/análise , Frutas/química , Fenóis/análise , Vitis/química , Vinho/análise , Manipulação de Alimentos/métodos , Polifenóis
14.
J Agric Food Chem ; 53(10): 3974-9, 2005 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-15884826

RESUMO

A dehydration postharvesting treatment is necessary to convert Crocus sativus L. stigmas into saffron spice. Three different dehydration treatments were evaluated: dehydration at room temperature; dehydration with hot air at different temperatures (70, 90, and 110 degrees C); and dehydration following traditional processing in Castille-La Mancha (Spain) with three different heating sources (vineshoot charcoal, gas cooker, and electric coil). The time (between 28 and 55 min) and mean temperature (between 54 and 83 degrees C) conditions for traditional dehydration were established for the first time. The highest coloring strength was obtained when saffron was submitted to higher temperatures and lower times. These findings may be supported by the fact that samples dehydrated at high temperature were more porous than those dehydrated at room temperature, as was observed by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The higher the temperature during the process, the higher the proportion of trans-crocetin di-(beta-D-gentibiosyl) ester, although trans-crocetin (beta-D-glucosyl)-(beta-D-gentibiosyl) and trans-crocetin di-(beta-D-glucosyl) ester decrease while cis-crocins did not change significantly. A thermal aging process reveals that the trans-crocetin di-(beta-D-gentibiosyl) ester increases when saffron is resubmitted to a heating treatment before it is decomposed by the extreme conditions. The picrocrocin extinction during the aging process does not imply a consistent generation of safranal.


Assuntos
Crocus/química , Dessecação/métodos , Flores/química , Varredura Diferencial de Calorimetria , Carotenoides/análise , Cor , Flores/ultraestrutura , Microscopia Eletrônica de Varredura , Temperatura , Fatores de Tempo
15.
J Agric Food Chem ; 52(15): 4821-7, 2004 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-15264921

RESUMO

The stir bar sorptive extraction (SBSE) technique is used to determine volatile constituents in Monastrell grapes. The method proposed involves a maceration step lasting 2 h and a sorption time of 6 h. The coefficients of variation obtained were <4% in the case of the volatile compounds and <2% for the internal standard. The behavior of the volatiles during grape ripening was studied, and 34 compounds were determined, among which geranyl acetone, geranyl butyrate, farnesol, and a bicycloterpene, tentatively identified as 6-methylene[3.1.0]byciclohexane, were recorded for the first time in this variety. The highest terpene and norisoprenoid contents together with the lowest values of C6 compounds were observed during the fifth week of ripening, meaning that this would be the optimal time for harvesting in terms of volatile compounds.


Assuntos
Frutas/química , Frutas/crescimento & desenvolvimento , Odorantes/análise , Vitis/crescimento & desenvolvimento , Álcoois/análise , Aldeídos/análise , Cromatografia Gasosa/métodos , Norisoprenoides/análise , Sensibilidade e Especificidade , Terpenos/análise , Volatilização
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