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1.
PLoS One ; 17(4): e0266368, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35421137

RESUMO

Wheat crop is very sensitive to osmotic stress conditions. As an abiotic stress, drought may exert a considerable effect on the levels of specialized metabolites in plants. These metabolites may exert beneficial biological activities in the prevention or treatment of disorders linked to oxidative stress in plants and humans. Furthermore, osmoprotector accumulation helps wheat to increase the maintenance of osmotic balance. Therefore, identifying wheat genotypes with better drought tolerance is extremely important. In this sense, this research aimed to understand agronomic, physiological and biochemical responses of spring wheat strains and cultivars to drought stress, under field conditions, and jointly select strains via multi-trait index. We evaluated agronomic, physiological and biochemical variables in 18 genotypes under field condition. The results demonstrated that all variables were affected by the drought. Most genotypes were significantly reduced in grain yield, except VI_14774, VI_14668, VI_9007 and TBIO_ATON. The variables related to photosynthesis were also affected. An increase above 800% was observed in proline contents in genotypes under drought. Sodium and potassium also increased, mainly for VI_131313 (Na), while VI_130758 and VI_14774 presented increased K. We evaluated the antioxidant potential of the different strains and the total content of phenolic compounds. The most drought-responsive genotypes were BRS_264, VI_14050 and VI_14426. Reduced grain yield and photosynthetic variables, and increased specialized metabolism compounds are due to plant defense mechanisms against drought conditions. Furthermore, variation in genotypes can be explained by the fact that each plant presents a different defense and tolerance mechanism, which may also occur between genotypes of the same species. Four strains were selected by the multivariate index: VI_14055, VI_14001, VI_14426 and VI_1466. Such results allow us to predict which genotype(s) performed best in semi-arid environments and under climatic fluctuations.


Assuntos
Secas , Triticum , Antioxidantes/metabolismo , Genótipo , Humanos , Fotossíntese/genética , Estresse Fisiológico/genética , Triticum/metabolismo
2.
Food Res Int ; 141: 110082, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33641964

RESUMO

The antihyperglicemic activity of crude extract from Moringa oleifera leaves and isolation of phenolic compounds with antioxidant activity using bioguided assay were employed by the first time in leaves cultivated in Brazil. The hydroalcoholic extract (HE) was produced by using ethanol:water (80:20 v/v) and purified by solid-liquid procedure using solvents in ascending order of polarity. The ethyl acetate fraction (Fr-EtOAc) presented high antioxidant potential and it was purified using chromatographic techniques rendering isolated compounds that were identified from the spectral data. The HE extract (500 mg kg-1) was adimistrated in diabetic rats induced by streptozotocin and chemical markers and lipid peroxidation in liver and kidney were evaluated. The Fr-EtOAc showed high antioxidant potential by FRAP reduction method (1678 µmol Fe2+ g-1), DPPH and ABTS scavenging methods (526.7 and 671.5 µmol TEAC g-1 respectively) and ORAC assay (3560.6 µmol TEAC g-1). Therefore, the Fr-EtOAc was purified and yielded three bioactive subfractions (S-12, S-13 abd S-15) that were rechromatoghaphed in HPLC-SemiPrep. After that, two main bioactive glycosylated flavonoids (isoquercitrin and astragalin) and phenolic acid (3-O-caffeoylquinic acid) were obtained. Additionally, the HE extract provided protection against oxidative damage in liver and kidney of diabetic rats ameliorating endogenous antioxidant defenses by increase catalase (CAT), glutathione S-transferase (GST) and non-protein thiol groups (NPSH) levels as well as decreased the lipid peroxidation in these tissues. Our results indicate that three phenolic compounds with high antioxidant activity were isolated and, the chemical composition of HE crude extract, rich in flavonoids glycosylated could be intimately related to antihyperglycemic action. So, it is possible to suggest that these compounds may be used as chemical biomarkers for this plant in Brazil, ensuring quality and supporting the use of aerial parts in tradicional medicine.


Assuntos
Diabetes Mellitus Experimental , Moringa oleifera , Animais , Antioxidantes/farmacologia , Brasil , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta , Ratos
3.
Molecules ; 25(21)2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33171894

RESUMO

This study aimed to evaluate the antioxidant activities (AA) of lyophilized rosemary extract and lyophilized sage extract, and their effects on the oxidative stability of poultry pátê. For this purpose, four poultry pátê formulations with rosemary, sage, sodium erythorbate and a control (without antioxidants) were produced. The rosemary and sage were characterized according to total phenolic compounds (TPC) and AA by several methods. The poultry pátês stored at 4 °C were evaluated by the lipid oxidation. High concentrations of TPC were detected in the rosemary extract and sage extract (46.48 and 41.61 mg GAE/g (Gallic acid equivalent), respectively). The AA of the rosemary and sage extracts determined by free radical-scavenging were 4745.72 and 2462.82 µmol TE/g (Trolox equivalents), respectively. The high concentrations of catechin, rutin, myricetin and p-coumaric acids in these extracts may be responsible for the strong inhibitory action against food pathogens. Besides this, these compounds can be responsible for the best performance in inhibiting lipid oxidation in poultry pátês during storage. This study suggests that rosemary and sage extracts may be used as a natural antioxidant in meat products.


Assuntos
Antioxidantes/farmacologia , Lipídeos/química , Extratos Vegetais/farmacologia , Produtos Avícolas , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Flavonoides/análise , Microbiologia de Alimentos , Armazenamento de Alimentos , Liofilização , Testes de Sensibilidade Microbiana , Oxirredução , Fenóis/análise , Extratos Vegetais/química , Rosmarinus/química , Salvia officinalis/química
4.
Molecules ; 25(10)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32455579

RESUMO

The aim of this study was to evaluate the most effective extraction condition (temperature, solvent type and time) for recovery of high-value phytochemicals present in the Tabernaemontana catharinensis leaves (TC) and to assess their effect on biochemical parameters in streptozotocin-induced diabetic rats. The extraction of phenolic compounds from TC using a factorial design (FD) 2³, high performance liquid chromatography (HPLC), response surface methodology (RSM) and principal component analysis (PCA) were studied. It was found that the optimal conditions for extraction of phenolics were higher temperature (65 °C) and time (60 min) using ethanol as extractor solvent. In this condition of extraction (A8), total phenolic compounds (TPC) and antioxidant activity (AA) were determined. Additionally, this extract was used to evaluate their effect on antioxidant enzyme activities (superoxide dismutase (SOD) and catalase (CAT)) as well as lipid peroxidation (LP) and protein thiols level (PSH) in the liver and kidneys of normal and diabetic rats. As result, T. catharinensis extract presented TPC content of 23.34 mg EAG/g (equivalent gallic acid) and AA of 34.26 µmol Trolox/g. Phenolic acids (ferulic acid and coumaric acid) and flavonoids (quercetin, rutin and pinocembrin) could be recovered and identified by HPLC. This study indicated an important role of the T. catharinensis extract on free radical inactivation and on the antioxidant defense system in diabetic rats. In fact, the use of T. catharinensis extract restored the normal activity of SOD (p < 0.05) and suppressed malondialdehyde levels in liver and kidney tissues. Thus, the T. catharinensis extract, rich in phenolic compounds, can be responsible for the recover the enzymatic changes in the liver and kidney tissues provoked by diabetes in rats. In addition, the lipid peroxidation rate decreased in the diabetic rats treated with T. catharinensis.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Fenóis/química , Tabernaemontana/química , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Diabetes Mellitus/patologia , Diabetes Mellitus Experimental/patologia , Humanos , Estresse Oxidativo/efeitos dos fármacos , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Ratos
5.
Food Res Int ; 125: 108647, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554035

RESUMO

Moringa oleifera leaves are used in Brazilian folk medicine for their hypoglycemic and nutritional properties. In this context, the chemical and biological characteristics were determined. Conventional successive solid-liquid extraction with simultaneous bioguided purification using solvents with different polarities was performed with M. oleifera leaves, yielding six fractions and extracts. The fractions showed better results for antioxidant activity than the extracts. All of them were evaluated by scavenging of synthetic free radicals and reactive oxygen species, and Fr-Ace and Fr-EtOAc showed >100 mg GAE g-1 of phenolic content, while for FRAP and ORAC assays the values were higher than 1600 µmol Fe2+ g-1 and 3500 mmol TEAC g-1 respectively. The UPLC-ESI-QTOF-MS analysis of hydroalcoholic extract (HE) allowed identifying 24 compounds, with flavonoid derivatives being the most abundant group. Furthermore, the alkaloid trigonelline and sesquiterpenoid abscisic acid were identified for the first time in M. oleifera leaves. Finally, gallic acid, caffeic acid, rutin and quercetin were found in concentrations of 16.5, 2129, 477.4 and 127.5 µg g-1 respectively in HE, all of which were higher in fractions and extracts. These results suggest that bioguided extraction is an important technique, due to its ability to concentrate active compounds in a logical and rational way. In addition, M. oleifera leaves grown in Brazil are an important source of phenolic compounds with antioxidant activity that can be used in food, nutraceutical and pharmaceutical products.


Assuntos
Moringa oleifera/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química , Ácidos Carbocíclicos/análise , Alcaloides/análise , Aminoácidos/análise , Antioxidantes/análise , Brasil , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
6.
ScientificWorldJournal ; 2014: 485287, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25478593

RESUMO

The extraction of mechanically separated meat has emerged as an attractive process. However, it increases the incorporation of oxygen and, consequently, of flavors due to rancidity. Thus, preservatives must be added. The objective of this study was to evaluate the shelf life of minced tilapia to replace synthetic preservatives with Hijiki and Nori seaweeds extracts. The application of the extracts had no effect on the chemical composition of the minced tilapia. The seaweed extracts had inhibitory effect on total volatile base nitrogen. The minced tilapia complied with the microbiological standard set by Brazilin law. The panelists detected no differences in the rancid aroma and only minor differences were detected in the color of the products. It can be concluded that the minced tilapia with added seaweed extracts were within quality standards during frozen storage.


Assuntos
Conservantes de Alimentos , Armazenamento de Alimentos , Alga Marinha/química , Tilápia , Animais , Análise de Alimentos , Carne , Oxigênio/metabolismo
7.
J Food Sci Technol ; 51(10): 2862-6, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25328239

RESUMO

The recovery of phenolic compounds of Eugenia pyriformis using different solvents was investigated in this study. The compounds were identified and quantified by reverse-phase high-performance liquid chromatography coupled with ultraviolet-visible diode-array detector (RP-HPLC-DAD/UV-vis). Absolute methanol was the most effective extraction agent of phenolic acids and flavonols (588.31 mg/Kg) from Eugenia pyriformis, although similar results (p ≤ 0.05) were observed using methanol/water (1:1 ratio). Our results clearly showed that higher contents of phenolic compounds were not obtained either with the most or the least polar solvents used. Several phenolic compounds were identified in the samples whereas gallic acid and quercetin were the major compounds recovered.

8.
Ciênc. agrotec., (Impr.) ; 31(6): 1818-1825, nov.-dez. 2007. graf, tab
Artigo em Inglês | LILACS | ID: lil-471702

RESUMO

The aim of this study was to determine the antioxidant activity, phenolic content and antibacterial activity of pollen extracts obtained with different concentrations of ethanol. Each extraction condition (ethanol solutions from 40 to 90 percent) had a different effect in the phenolic compounds content. Although, the pollen extract obtained at 60, 70 and 80 percent of ethanol showed relatively higher levels of phenolic compounds (>10 mg/g) and did not present statistical significant difference between the extraction conditions. The amount of total phenolics ranged from 3.6 to 8.1 and 6.6 to 10.9 mg GAE/g for Alagoas state and Parana state pollen, respectively. The higher value for antioxidant activity index was 83.30 percent for the pollen from Alagoas state and 81.15 percent for Parana state pollen. The highest degree of antioxidant activity was found in the extraction at 60 percent of ethanol solution for Parana state pollen, which also showed the highest concentration of polyphenol compounds. Staphylococcus aureus was inhibited by the ethanolic extract of Alagoas state pollen in all the concentrations of solvent, except the ethanolic extract of pollen at 90 percent. The extract at 60 percent of ethanol solution (Parana sample) inhibited Bacillus subtilis, Pseudomonas aeruginosa and Klebsiella sp.


Objetivou-se, neste estudo determinar compostos fenólicos, a atividade antioxidante a antibacteriana dos extratos etanólicos de pólen, obtidos com diferentes concentrações de etanol. As diferentes condições de extração (etanol de 40 a 90 por cento) apresentaram diferentes efeitos no conteúdo dos compostos fenólicos extraídos. Os extratos de pólen obtidos com etanol a 60, 70 e 80 por cento apresentaram maiores níveis de compostos fenólicos (>10 mg/g) e não apresentaram diferenças estatísticas entre essas condições de extração. A quantidade de compostos fenólicos nos extratos de pólen variou de 3.6 a 8.1 e 6.6 a 11 mg de equivalente em ácido gálico por g de pólen (GAE), para os estados de Alagoas e Paraná, respectivamente. Os maiores índices de atividade antioxidante para o pólen do estado de Alagoas foi de 83.30 por cento e 81.15 por cento para o pólen do estado do Paraná. O pólen do estado do Paraná extraído com etanol a 60 por cento, apresentou o maior índice de atividade antioxidante e também a maior concentração de compostos fenólicos. A bactéria Staphylococcus aureus foi inibida pelo extrato etanólico do pólen de Alagoas, em todas as concentrações, exceto no extrato etanólico a 90 por cento. O extrato etanólico a 60 por cento, no pólen do Paraná, inibiu Bacillus subtilis, Pseudomonas aeruginosa e Klebsiella sp.

9.
Bol. Centro Pesqui. Process. Aliment ; 24(2): 347-362, jul.-dez. 2006. tab
Artigo em Português | LILACS | ID: lil-452796

RESUMO

O objetivo deste trabalho foi reunir informações atualizadas sobre os substitutos de gordura, abrangendo a diversidade desses ingredientes e seu potencial de aplicação. Foram abordados os substitutos de gordura derivados de carboidratos, de lipídios e de proteínas, bem como a combinação dessas tres categorias. Verificou-se que os substitutos de gordura podem ser facilmente incorporados em muitos alimentos como, laticínios, queijos, bebidas, produtos de panificação, chocolates, molhos para saladas, maionese e sobremesas. A mais nova geração de substitutos de gordura tem incentivado a revolução dos alimentos com baixo conteúdo calórico, devido principalmente à demanda proveniente de consumidores preocupados com a saúde. Essa demanda tem permitido o avanço tecnológico e muitas melhorias estão sendo efetuadas com relação à funcionalidade e a palatabilidade desses produtos


Assuntos
Substitutos da Gordura , Tecnologia de Alimentos
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