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2.
Arch Soc Esp Oftalmol (Engl Ed) ; 96(10): 545-548, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34620484

RESUMO

Monocular elevation deficiency (MED) is characterized by unilateral limitation of supraductions, similar in adduction and abduction, in addition to hypotropia and ptosis. We describe a case of a 62-year-old woman with long-standing left ptosis who was initially operated with a frontal suspension technique. On subsequent examinations, a MED of that eye was found. The passive duction test was positive, so the inferior rectus was recessed. In addition, a modified Nishida technique was performed, consisting of the scleral anchorage of the superior edges of the rectus, medial and lateral, 12mm from the corneal limbus in the superonasal and superotemporal quadrants, respectively. Postoperatively, the left eye presented a minimal hypotropia of 3 PD. This modified technnique used here on the horizontal rectus muscles, turned out to be effective and safe for the correction of MED.


Assuntos
Blefaroptose , Estrabismo , Blefaroptose/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Músculos Oculomotores/cirurgia , Procedimentos Cirúrgicos Oftalmológicos , Esclera , Estrabismo/cirurgia
3.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33342631

RESUMO

Monocular elevation deficiency (MED) is characterized by unilateral limitation of supraductions, similar in adduction and abduction, in addition to hypotropia and ptosis. We describe a case of a 62-year-old woman with long-standing left ptosis who was initially operated with a frontal suspension technique. On subsequent examinations, a MED of that eye was found. The passive duction test was positive, so the inferior rectus was recessed. In addition, a modified Nishida technique was performed, consisting of the scleral anchorage of the superior edges of the rectus, medial and lateral, 12mm from the corneal limbus in the superonasal and superotemporal quadrants, respectively. Postoperatively, the left eye presented a minimal hypotropia of 3 PD. This modified technnique used here on the horizontal rectus muscles, turned out to be effective and safe for the correction of MED.

5.
Microorganisms ; 8(9)2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899614

RESUMO

Yeasts are the key microorganisms that transform grape juice into wine, and nitrogen is an essential nutrient able to affect yeast cell growth, fermentation kinetics and wine quality. In this work, we focused on the intra- and extracellular metabolomic changes of three aromatic amino acids (tryptophan, tyrosine, and phenylalanine) during alcoholic fermentation of two grape musts by two Saccharomyces cerevisiae strains and the sequential inoculation of Torulaspora delbrueckii with Saccharomyces cerevisiae. An UPLC-MS/MS method was used to monitor 33 metabolites, and 26 of them were detected in the extracellular samples and 8 were detected in the intracellular ones. The results indicate that the most intensive metabolomic changes occurred during the logarithm cellular growth phase and that pure S. cerevisiae fermentations produced higher amounts of N-acetyl derivatives of tryptophan and tyrosine and the off-odour molecule 2-aminoacetophenone. The sequentially inoculated fermentations showed a slower evolution and a higher production of metabolites linked to the well-known plant hormone indole acetic acid (auxin). Finally, the production of sulfonated tryptophol during must fermentation was confirmed, which also may explain the bitter taste of wines produced by Torulaspora delbrueckii co-fermentations, while sulfonated indole carboxylic acid was detected for the first time in such an experimental design.

6.
J Agric Food Chem ; 67(28): 7942-7953, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31264861

RESUMO

Tryptophan, phenylalanine, and tyrosine play an important role as nitrogen sources in yeast metabolism. They regulate biomass production and fermentation rate, and their catabolites contribute to wine health benefits and sensorial character through the yeast biotransformation of grape juice constitutes into biologically active and flavor-impacting components. A UHPLC-MS/MS method was applied to monitor 37 tryptophan/phenylalanine/tyrosine yeast metabolites both in extra- and intracellular extracts produced by the fermentation of two Saccharomyces cerevisiae strains and one Torulaspora delbrueckii. The results shed light on the intra- and extra-cellular metabolomic dynamics, by combining metabolic needs, stimuli, and signals. Among others, the results indicated (a) the production of 2-aminoacetophenone by yeasts, mainly by the two Saccharomyces cerevisiae; (b) the deactivation and/or detoxification of tryptophol via sulfonation reaction; and (c) the deacetylation of N-acetyl tryptophan ethyl ester and N-acetyl tyrosine ethyl ester by producing the corresponding ethyl esters.


Assuntos
Aminoácidos Aromáticos/metabolismo , Saccharomyces cerevisiae/metabolismo , Torulaspora/metabolismo , Aminoácidos Aromáticos/química , Cromatografia Líquida de Alta Pressão , Nitrogênio/metabolismo , Saccharomyces cerevisiae/química , Espectrometria de Massas em Tandem , Torulaspora/química
7.
Food Chem ; 297: 124924, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253284

RESUMO

Yeast nitrogen metabolism produces metabolites, whose origin in wines has scarcely been studied, with an important biological and organoleptic role. The present work focuses on comparing three intracellular extraction methods in order to elucidate efficiency of extraction while measuring the effect of temperature upon the integrity of the compounds related to the metabolism of tryptophan and tyrosine by yeast. Two UHPLC/HRMS methods to measure 16 metabolites were developed and validated. The validation provided optimum values of LOD (7.4·10-6 to 0.1 µg L-1), of LOQ (2·10-5 to 0.02 µg L-1) of precision (11-0.5% RSD) and repeatability (12-0.5% RSD). The removal of interfering molecules enabled matrix effects to be kept at low levels. The results pointed out that the low-temperature methods were more effective, providing better precision for 16 metabolites. The high-temperature extraction method may yield false enhanced compounds concentrations since they originate in cell wall macromolecules degradation.


Assuntos
Fracionamento Químico/métodos , Saccharomyces cerevisiae/metabolismo , Triptofano/análise , Tirosina/análise , Cromatografia Líquida de Alta Pressão , Temperatura Baixa , Congelamento , Glicerol/química , Espectrometria de Massas , Nitrogênio/metabolismo , Triptofano/metabolismo , Tirosina/metabolismo , Vinho/análise
8.
Rev Esp Anestesiol Reanim (Engl Ed) ; 66(2): 113-116, 2019 Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30447897

RESUMO

X-linked adrenoleukodystrophy (X-ALD) belongs to a family of rare diseases due to inborn errors of metabolism. It has a wide spectrum of clinical manifestations that anaesthesiologists should recognise during the perioperative period (respiratory centre dysfunction, hypotonia, adrenal or hepatic failure, gastroesophageal reflux disease, osteopenia, seizures).The case is presented of a 42-year-old X-linked adrenoleukodystrophy female carrier, who underwent combined general and an ultrasound-guided interscalene brachial plexus block anaesthesia for shoulder arthroscopy. Induction was performed with thiopentone and fentanyl, and sevoflurane was used as inhaled maintenance agent. No events were recorded during the procedure. Her post-operative recovery was satisfactory and she was later discharged home.


Assuntos
Adrenoleucodistrofia/genética , Artroscopia , Bloqueio do Plexo Braquial/métodos , Heterozigoto , Ombro/cirurgia , Adulto , Anestesia Geral , Anestésicos , Feminino , Fentanila , Humanos , Sevoflurano , Tiopental
9.
Rev Esp Quimioter ; 31(4): 336-343, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29956896

RESUMO

OBJECTIVE: The prevalence of Pneumocystis jirovecii colonization and its role in pulmonary disease remains unclear. PCR methods have shown an improved sensitivity in the detection of this fungus. It has been suggested that the PCR results be combined with another test such as IFA to create a diagnostic algorithm. METHODS: A multiplex nested-PCR procedure with a 16S rRNA gene as the internal amplification control was evaluated to determine the role of P. jirovecii in pulmonary disease. RESULTS: A 20% of the 199 bronchoalveolar lavage samples were PCR-positive, 13.5% samples were PCR-inhibited, and the rate of Pneumocystis-colonisation was 6.4%. The sensitivity, specificity, positive predictive value and negative predictive value of the nested-PCR were 100%, 93%, 70% and 100%, respectively. The sensitivity of the nested-PCR was higher than the current "gold standard" immunofluorescence assay (IFA) (p< 0.0001). PCR-negative and PCR-positive patients did not show any clinical or radiological differences in the medical variables studied. CONCLUSIONS: PCR could help the diagnosis of Pneumocystis pulmonary disease given the high negative predictive value of the technique. P. jirovecii DNA can frequently be detected in healthy population, so the analysis of the patient medical history is critical to make the correct clinical decision.


Assuntos
Pneumopatias/complicações , Pneumocystis carinii , Pneumonia por Pneumocystis/complicações , Pneumonia por Pneumocystis/diagnóstico , Reação em Cadeia da Polimerase/métodos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Líquido da Lavagem Broncoalveolar/microbiologia , DNA Bacteriano/genética , Feminino , Humanos , Pneumopatias/tratamento farmacológico , Pneumopatias/microbiologia , Masculino , Pessoa de Meia-Idade , Pneumocystis carinii/genética , Valor Preditivo dos Testes , RNA Bacteriano/genética , RNA Ribossômico 16S/genética
10.
Food Chem ; 242: 345-351, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29037699

RESUMO

Hydroxytyrosol (HT) is a phenolic compound of recognized bioactivity that has been described in wines but little is known about its origin. This work demonstrates that yeast involved in wine making, i.e. Saccharomyces cerevisiae strains and the non-Saccharomyces Torulaspora delbrueckii, can synthesise HT, as this compound was identified in the intracellular media of three strains by means of a developed and validated UHPLC-HRMS method with LOQ and LOD of 0.108 and 0.035ngmL-1 respectively. Controlled fermentations were performed with different varieties of grapes (Corredera, Moscatel, Chardonnay, Palomino fino, Sauvignon Blanc, Vijiriega, and Tempranillo) and synthetic must. The Saccharomyces cerevisiae strain QA23 was the most efficient producer of HT from tested yeasts. On the other hand, the grape variety influences HT wine concentrations. Furthermore, the maximum concentration of HT is reached between the fourth and sixth day of fermentation. This work reveals that yeasts have a great potential for the production of HT.


Assuntos
Fermentação , Álcool Feniletílico/análogos & derivados , Saccharomyces cerevisiae/metabolismo , Torulaspora/metabolismo , Vinho/análise , Cromatografia Líquida de Alta Pressão , Álcool Feniletílico/análise , Álcool Feniletílico/metabolismo , Vitis
11.
Nutrients ; 9(3)2017 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-28282869

RESUMO

Excessive concentrations of vascular endothelial growth factor (VEGF) trigger angiogenesis, which causes complications such as the destabilization of atherosclerotic plaques and increased growth of tumors. This work focuses on the determination of the inhibitory activity of melatonin and other indolic related compounds on VEGF-induced VEGF receptor-2 (VEGFR-2) activation and an approximation to the molecular mechanism underlying the inhibition. Quantification of phosphorylated VEGFR-2 was measured by ELISA. Migration wound-healing assay was used to determine cell migration of human umbilical vein endothelial cells (HUVECs). This is the first time that melatonin, 3-indolacetic acid, 5-hydroxytryptophol, and serotonin are proved to significantly inhibit VEGF-induced VEGFR-2 activation in human umbilical vein endothelial cells and subsequent angiogenesis. 3-Indolacetic acid showed the highest inhibitory effect (IC50 value of 0.9704 mM), followed by 5-hydroxytryptophol (35% of inhibition at 0.1 mM), melatonin (30% of inhibition at 1 mM), and serotonin (24% of inhibition at 1 mM). An approximation to the molecular mechanism of the inhibition has been proposed, suggesting that indolic compounds might interact with the cell surface components of the endothelial membrane in a way that prevents VEGF from activating the receptor. Additionally, wound-healing assay revealed that exposure of HUVECs to melatonin and 3-indolacetic acid in the presence of VEGF significantly inhibited cell migration by 87% and 99%, respectively, after 24 h. These data demonstrate that melatonin, 3-indolacetic acid, 5-hydroxytryptophol, and serotonin would be good molecules for future exploitation as anti-VEGF signaling agents.


Assuntos
Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Indóis/farmacologia , Melatonina/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Inibidores da Angiogênese/farmacologia , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Fosforilação
12.
J Food Sci ; 82(2): 364-372, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28071800

RESUMO

Anthocyanins are the major polyphenolic compounds in strawberry fruit responsible for its color. Due to their sensitivity, they are affected by food processing techniques such as fermentation that alters both their chemical composition and organoleptic properties. This work aims to evaluate the impact of different fermentation processes on individual anthocyanins compounds in strawberry wine and vinegar by UHPLC-MS/MS Q Exactive analysis. Nineteen, 18, and 14 anthocyanin compounds were identified in the strawberry initial substrate, strawberry wine, and strawberry vinegar, respectively. Four and 8 anthocyanin compounds were tentatively identified with high accuracy for the 1st time to be present in the beverages obtained by alcoholic fermentation and acetic fermentation of strawberry, respectively. Both, the total and the individual anthocyanin concentrations were decreased by both fermentation processes, affecting the alcoholic fermentation to a lesser extent (19%) than the acetic fermentation (91%). Indeed, several changes in color parameters have been assessed. The color of the wine and the vinegar made from strawberry changed during the fermentation process, varying from red to orange color, this fact is directly correlated with the decrease of anthocyanins compounds.


Assuntos
Antocianinas/química , Fragaria/química , Vinho/análise , Ácido Acético/análise , Bebidas/análise , Cor , Fermentação , Manipulação de Alimentos/métodos , Frutas/química , Espectrometria de Massas em Tandem
13.
Food Chem ; 217: 431-437, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27664655

RESUMO

Melatonin is a neurohormone involved in the regulation of circadian rhythms in humans. Evidence has recently been found of its occurrence in wines and its role in the winemaking process. The yeast Saccharomyces cerevisiae is consequently thought to be important in Melatonin synthesis, but limited data and reference texts are available on this synthetic pathway. This paper aims to elucidate whether the synthetic pathway of Melatonin in Saccharomyces and non-Saccharomyces strains involves these intermediates. To this end, seven commercial strains comprising Saccharomyces cerevisiae (Red Fruit, ES488, Lalvin QA23, Uvaferm BC, and Lalvin ICV GRE) and non-Saccharomyces (Torulaspora delbrueckii and Metschnikowia pulcherrima) were monitored, under controlled fermentation conditions, in synthetic must, for seven days. Samples were analysed using a UHPLC-HRMS system (Qexactive). Five out of the seven strains formed Melatonin during the fermentation process: three S. cerevisiae strains and the two non-Saccharomyces. Additionally, other compounds derived from l-tryptophan occurred during fermentation.


Assuntos
Fermentação/fisiologia , Melatonina/metabolismo , Saccharomyces cerevisiae/metabolismo , Triptofano/metabolismo , Vinho , Aromatizantes/isolamento & purificação , Aromatizantes/metabolismo , Melatonina/isolamento & purificação , Saccharomyces/metabolismo , Triptofano/isolamento & purificação , Vinho/análise
14.
J Antimicrob Chemother ; 71(7): 2022-30, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27029851

RESUMO

OBJECTIVES: Although controversy exists regarding the efficacy of antibiotic prophylaxis for patients at risk of infective endocarditis, expert committees continue to publish recommendations for antibiotic prophylaxis regimens. This study aimed to evaluate the efficacy of four antimicrobial regimens for the prevention of bacteraemia following dental extractions. METHODS: The study population included 266 adults requiring dental extractions who were randomly assigned to the following five groups: control (no prophylaxis); 1000/200 mg of amoxicillin/clavulanate intravenously; 2 g of amoxicillin by mouth; 600 mg of clindamycin by mouth; and 600 mg of azithromycin by mouth. Venous blood samples were collected from each patient at baseline and at 30 s, 15 min and 1 h after dental extractions. Samples were inoculated into BACTEC Plus culture bottles and processed in the BACTEC 9240. Conventional microbiological techniques were used for subcultures and further identification of the isolated bacteria. The trial was registered at ClinicalTrials.gov with ID number NCT02115776. RESULTS: The incidence of bacteraemia in the control, amoxicillin/clavulanate, amoxicillin, clindamycin and azithromycin groups was: 96%, 0%, 50%, 87% and 81%, respectively, at 30 s; 65%, 0%, 10%, 65% and 49% at 15 min; and 18%, 0%, 4%, 19% and 18% at 1 h. Streptococci were the most frequently identified bacteria. The percentage of positive blood cultures at 30 s post-extraction was lower in the amoxicillin/clavulanate group than in the amoxicillin group (P < 0.001). The incidence of bacteraemia in the clindamycin group was similar to that in the control group. CONCLUSIONS: Bacteraemia following dental extractions was undetectable with amoxicillin/clavulanate prophylaxis. Alternative antimicrobial regimens should be sought for patients allergic to the ß-lactams.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/administração & dosagem , Antibacterianos/administração & dosagem , Antibioticoprofilaxia/métodos , Bacteriemia/prevenção & controle , Extração Dentária/efeitos adversos , Inibidores de beta-Lactamases/administração & dosagem , Administração Intravenosa , Adolescente , Adulto , Técnicas Bacteriológicas , Sangue/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
15.
J Agric Food Chem ; 64(6): 1367-76, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26803927

RESUMO

Overproduction of strawberry leads to food waste, as it is very perishable. Therefore, strategies to transform it into new products are appreciated. This research focuses on characterization of the nonanthocyanin phenolic content of a beverage obtained from strawberry by gluconic and acetic fermentation and subsequently monitored for 90 days of storage, at two temperatures. Sixty-four nonanthocyanin (poly)phenols were identified by high-resolution mass spectrometry (UHPLC coupled with linear trap quadrupole and Orbitrap mass analyzer) and, for the first time, four compounds were reported in beverages fermented from strawberry: aromadendrin hexoside, phloretin 2'-O-xylosyl glucoside, dihydroferulic acid 4-O-glucuronide, and kaempferol hexosyl hexoside. During the storage time the increase in protocatechuic acid content was 13 times and condensed tannins diminished, especially procyanidin trimer. Statistical analysis showed that the composition remains unchanged until day 15 of storage at room temperature (27-30 °C) and until day 30 under refrigerated conditions (4 °C).


Assuntos
Bebidas/análise , Armazenamento de Alimentos/métodos , Fragaria/química , Fenol/química , Cromatografia Líquida de Alta Pressão/métodos , Aromatizantes/química , Espectrometria de Massas em Tandem/métodos
16.
Antimicrob Agents Chemother ; 59(11): 6725-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26282428

RESUMO

Neither breakpoints (BPs) nor epidemiological cutoff values (ECVs) have been established for Candida spp. with anidulafungin, caspofungin, and micafungin when using the Sensititre YeastOne (SYO) broth dilution colorimetric method. In addition, reference caspofungin MICs have so far proven to be unreliable. Candida species wild-type (WT) MIC distributions (for microorganisms in a species/drug combination with no detectable phenotypic resistance) were established for 6,007 Candida albicans, 186 C. dubliniensis, 3,188 C. glabrata complex, 119 C. guilliermondii, 493 C. krusei, 205 C. lusitaniae, 3,136 C. parapsilosis complex, and 1,016 C. tropicalis isolates. SYO MIC data gathered from 38 laboratories in Australia, Canada, Europe, Mexico, New Zealand, South Africa, and the United States were pooled to statistically define SYO ECVs. ECVs for anidulafungin, caspofungin, and micafungin encompassing ≥97.5% of the statistically modeled population were, respectively, 0.12, 0.25, and 0.06 µg/ml for C. albicans, 0.12, 0.25, and 0.03 µg/ml for C. glabrata complex, 4, 2, and 4 µg/ml for C. parapsilosis complex, 0.5, 0.25, and 0.06 µg/ml for C. tropicalis, 0.25, 1, and 0.25 µg/ml for C. krusei, 0.25, 1, and 0.12 µg/ml for C. lusitaniae, 4, 2, and 2 µg/ml for C. guilliermondii, and 0.25, 0.25, and 0.12 µg/ml for C. dubliniensis. Species-specific SYO ECVs for anidulafungin, caspofungin, and micafungin correctly classified 72 (88.9%), 74 (91.4%), 76 (93.8%), respectively, of 81 Candida isolates with identified fks mutations. SYO ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin, micafungin, and especially caspofungin, since testing the susceptibilities of Candida spp. to caspofungin by reference methodologies is not recommended.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Equinocandinas/farmacologia , Lipopeptídeos/farmacologia , Anidulafungina , Candida/genética , Caspofungina , Micafungina , Testes de Sensibilidade Microbiana , Mutação/genética
17.
J Agric Food Chem ; 63(7): 2041-51, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25598511

RESUMO

In this study, the nonanthocyanin (poly)phenolic profile of an alcoholic-fermented strawberry beverage was characterized. High-performance liquid chromatography coupled with a triple-quadropole mass spectrometer and ultra-high-performance liquid chromatography coupled with a linear trap quadropole and an Orbitrap mass analyzer was used to identify nonanthocyanin phenolic compounds. Sixty-six compounds were identified, and 13 of these were identified for the first time in strawberry or its derived alcoholic fermented beverage: protocatechuic acid-4-O-ß-hexoside, brevifolin carboxylic acid, ferulic acid glucuronide, dimer caffeic acid-O-hexoside, luteolin-3'-O-xyloside, isorhamnetin 3-O-glucoside, taxifolin-O-glucoside, (+)-aromadendrin rhamnoside, eriodictyol-7-O-glucoside, (+)-taxifolin, (+)-aromadendrin, eriodictyol, and homovanillic acid. The alcoholic fermentation process produced significant increases in certain compounds, such as homovanillic acid and p-hydroxybenzoic acid, while a significant decrease in galloyl bis-HHDP-glucose was observed. Linear discriminant analysis correctly classified samples initial, final, and pasteurized, which led to the conclusion that alcoholic fermentation induces significant changes in composition, mainly in relation to the 19 compounds represented in the tables of this work.


Assuntos
Antocianinas/química , Fragaria/química , Extratos Vegetais/química , Polifenóis/química , Bebidas Alcoólicas , Cromatografia Líquida de Alta Pressão , Fermentação , Espectrometria de Massas
18.
Food Chem ; 164: 104-12, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24996312

RESUMO

Strawberries are harvested in a short period of time frequently involving fruit surplus. This paper studies the impact of the strawberry purée elaboration process on the chemical composition of the final products. Thirty-two phenolic compounds were studied by Liquid Chromatography with Diode Array Detector (LC-DAD) and Mass Spectrometry (LC-MS). An LC-DAD method was set up and validated and the non-anthocyanin phenolic profile was quantified at the different steps of production, for three elaboration processes and two harvests (2011 and 2012). We have tentatively identified apigenin-7-O-glucoside, luteolin-3-O-glucuronide, malonyl caffeoylquinic acid, trans-resveratrol glucoside and caffeoylglucaric isomer. (+)-Catechin and HHDP-galloylglucose were the most abundant phenolic compounds. The most abundant flavonol was kaempferol-3-glucoside. The purée maintains the fruit's non-anthocyanin phenolic composition and in vitro antioxidant activity as determined by ORAC and DPPH methods. This fact suggests that strawberry purée could be considered a valuable ingredient for producing food derivatives.


Assuntos
Antioxidantes/análise , Manipulação de Alimentos/métodos , Fragaria/química , Frutas/química , Fenóis/análise , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Flavonóis/análise , Oxirredução
19.
J Agric Food Chem ; 62(19): 4369-76, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24779921

RESUMO

Wood shavings are widely employed in vinegar making to reduce aging time. Accordingly, this study aims to evaluate the effects of using shavings from different wood species (acacia, cherry, chestnut, and oak) and of toasting on the release of phenolic compounds into vinegar during the aging process. The study involved aging vinegars using previously toasted shavings and untoasted ones, at 0.5% and 1% (w/v), and collecting samples at 15 and 30 days. The phenolic compounds were analyzed by LC-DAD during the aging process. As a result, wood markers naringenin and kaempferol (cherry), robinetin and fustin (acacia), and isovanillin (oak) were identified for the first time in vinegars. The results also showed that toasting wood shavings decreases the concentration of most flavonoid wood markers (e.g., (+)-taxifolin, naringenin, and fustin) in vinegar, but that it is essential for the highest releases of aldehyde compounds (syringaldehyde, protocatechualdehyde, and vanillin). Remarkably, 15 days was sufficient to obtain the highest increases of most polyphenol compounds in the vinegar. Statistical analysis (linear discriminant analysis) proved that the phenolic compounds identified in vinegars are useful for discriminating vinegars regarding the wood species of the shavings used to accelerate aging.


Assuntos
Acacia/química , Manipulação de Alimentos/instrumentação , Fenóis/química , Prunus/química , Quercus/química , Vinho/análise , Cromatografia Líquida , Aromatizantes/química , Fatores de Tempo , Madeira/química
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