Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Food Chem ; 440: 138281, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38160597

RESUMO

Oxidative/nitrosative damage takes part in chronic disease development, which generates an urgent need for intervention and better therapies to manage them. The scientific community has demanded easy-to-run, cheap, and reliable methods for cellular antioxidant activity assays. This work standardised and validated an erythrocyte cellular antioxidant activity and membrane protection/injury (HERYCA-P) protocol to study food-derive extracts. The method measures intracellular reactive oxygen species (ROS) generation, lipoperoxidation, and haemolysis induced by 2,2'-azobis(2-amidinopropane) dihydrochloride. Quercetin decreased ROS generation by 50.4% and haemolysis by 2.2%, while ascorbic acid inhibited lipid peroxidation by 40.1%. Total phenolic contents of teas were correlated with decreased ROS generation (r = -0.924), lipoperoxidation (r = -0.951), and haemolysis (r = -0.869). The erythrocyte ROS generation and lipoperoxidation were also associated with CUPRAC (r = -0.925; r = -0.951) and hydroxyl radical scavenging activity (r = -0.936; r = -0.949). The precision rates of antioxidant standards and tea samples were below 15%. HERYCA-P is feasible as a complementary antioxidant assay for food matrices.


Assuntos
Antioxidantes , Hemólise , Humanos , Antioxidantes/farmacologia , Espécies Reativas de Oxigênio , Eritrócitos , Estresse Oxidativo , Peroxidação de Lipídeos , Fenóis/farmacologia , Extratos Vegetais/farmacologia
2.
Food Chem ; 381: 132284, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35121317

RESUMO

This study aimed to characterise pressurised hot water (PHW) extracts from nonconventional sources of functional carbohydrates and phenolic compounds in terms of antioxidant capacity, antiviral activity, toxicity, and human erythrocytes' protection antidiabetic potential. PHW extracts of Norway spruce bark (E1 + E2) and Birch sawdust (E3 + E4) contained mostly galactoglucomannan and glucuronoxylan. In contrast, samples E5 to E9 PHW extracted from Norway spruce, and Scots pine bark are rich sources of phenolic compounds. Overall, phenolic-rich extracts presented the highest inhibition of α-amylase and α-glucosidase and protection against stable non-enveloped enteroviruses. Additionally, all extracts protected human erythrocytes from hemolysis. Cell-based experiments using human cell lines (IMR90 and A549) showed extracts' non-toxicin vitroprofile. Considering the relative toxicological safety of extracts from these unconventional sources, functional carbohydrates and polyphenol-rich extracts can be obtained and further used in food models.


Assuntos
Ingredientes de Alimentos , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Florestas , Humanos , Mananas , Extratos Vegetais/farmacologia , Polissacarídeos , Xilanos
3.
Food Chem ; 361: 130078, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34023692

RESUMO

Ora-pro-nobis (Pereskia aculeata Miller) is a non-conventional food plant common in Brazil. The objective of this study was to optimize the extraction of bioactive phenolic compounds from ora-pro-nobis leaves by employing solvent mixtures. Ten extracts were obtained with water, ethanol, acetone, and their binary and ternary mixtures, evaluating the chemical composition, antioxidant activity and bioactivities in vitro. The response surface methodology was applied to model the results and calculate the optimal solvent composition, which is 60% water, 40% ethanol and 0% acetone. The optimized extract is rich in phenolic compounds (64 mg GAE/g) and proteins (823 mg/g) and presents antioxidant activity (in intracellular media as well) and inhibits lipid peroxidation (32%) along with hypotonic hemolysis (H50 = 0.339%), it does not present toxicity in vitro against cancer and normal cells. This is the first report of chicoric, caffeoyl-hexaric and coumaroyl-hexaric acids and some glycosylate derivatives of flavonols in ora-pro-nobis leaves.


Assuntos
Antioxidantes/química , Cactaceae/química , Extratos Vegetais/química , Antioxidantes/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química
4.
Food Chem ; 334: 127565, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32717686

RESUMO

The chemical composition, antioxidant activity (AA), cytotoxic activity, antihemolytic effects, and enzyme inhibition (EI) of lyophilized jabuticaba (Myrciaria jaboticaba) seed extract (LJE) was studied. The main compounds found were castalagin, vescalagin, procyanidin A2, and ellagic acid. LJE was more toxic to cancer cells than to normal cells, meaning relative toxicological safety. This cytotoxic effect can be attributed to the pro-oxidant effect observed in the reactive oxygen species (ROS) generation assay. LJE inhibited α-amylase, α-glucosidase, and ACE-I activities and protected human erythrocytes from hemolysis. LJE was incorporated into yogurts at different concentrations and the total phenolic content, AA, and EI increased in a dose-dependent manner. LJE-containing yogurt presented 86% sensory acceptance. The yogurt was administered to Wistar rats bearing cancer and it modulated the gut bacterial microbiota, having a prebiotic effect. LJE is a potential functional ingredient for food companies looking for TPC, AA, and prebiotic effect in vivo.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Myrtaceae/química , Polifenóis/farmacologia , Iogurte , 1,2-Dimetilidrazina/toxicidade , Inibidores da Enzima Conversora de Angiotensina/química , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Catequina/análise , Catequina/farmacologia , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/microbiologia , Humanos , Taninos Hidrolisáveis/análise , Taninos Hidrolisáveis/farmacologia , Masculino , Fenóis/análise , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/análise , Proantocianidinas/análise , Proantocianidinas/farmacologia , Ratos Wistar , Sementes/química , alfa-Amilases/antagonistas & inibidores
5.
Food Chem Toxicol ; 142: 111439, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32450285

RESUMO

The aim of this study was to evaluate the effects of different solvents and maximize the extraction of bioactive compounds from jabuticaba (Myrciaria cauliflora) seeds. In general, the solvent system composed of water and propanone (52:48 v/v) modified the extract polarity and increased extraction yield of bioactive compounds. The optimized extract presented antioxidant capacity measured by different chemical and biological assays. The optimized extract exerted antiproliferative and cytotoxic effects against A549 and HCT8 cells, antimicrobial and antihemolytic effects, inhibited α-amylase/α-glucosidase activities and presented in vitro antihypertensive effect. Nonetheless, the optimized extract showed no cytotoxicity in a human cell model (IMR90). Vescalagin, castalagin and ellagic acid were the major phenolic compounds in the optimized extract. Our results show that jabuticaba seed may be a potential ingredient for the development of potentially functional foods.


Assuntos
Myrtaceae/embriologia , Fenóis/análise , Extratos Vegetais/farmacologia , Sementes/química , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Anti-Infecciosos/farmacologia , Anti-Hipertensivos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Humanos , Hipoglicemiantes/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Sensibilidade Microbiana
6.
Food Chem ; 310: 125909, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31816536

RESUMO

Camu-camu (Myrciaria dubia) seeds are discarded without recovering the bioactive compounds. The main aim of the present work was to optimise the solvent mixture to extract higher total phenolic content and antioxidant capacity of camu-camu seeds. The optimised solvent system increased the extraction of phenolic compounds, in which vescalagin and castalagin were the main compounds. The optimised extract displayed antioxidant capacity measured by different chemical and biological assays, exerted antiproliferative and cytotoxic effects against A549 and HCT8 cancer cells, antimicrobial effects, protected human erythrocytes against hemolysis, inhibited α-amylase and α-glucosidase enzymes and presented in vitro antihypertensive effect. Additionally, the optimized extract inhibited human LDL copper-induced oxidation in vitro and reduced the TNF-α release and NF-κB activation in macrophages cell culture. Thus, the use of camu-camu seed showed to be a sustainable way to recover bioactive compounds with in vitro functional properties.


Assuntos
Myrtaceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos/métodos , Hemólise/efeitos dos fármacos , Humanos , Taninos Hidrolisáveis/análise , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Fenóis/análise , Sementes/química , alfa-Amilases/antagonistas & inibidores
7.
Food Res Int ; 125: 108516, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554085

RESUMO

The main objectives of the study were to compare the phenolic composition, chemical and biological antioxidant activities, and cytotoxicity towards IMR90, HCT8, and A549 cell lines of eight grades of Chinese keemun black tea (Camellia sinensis var. sinensis) using a statistical approach. No cytotoxic effects were observed on IMR90 normal cells. Our results all together show that the chemical antioxidant capacity of high-grade black teas measured by DPPH, FRAP, and total reducing capacity assays was correspondingly higher than the mean values of low-grade teas and these antioxidant assays were not associated with cytotoxicity towards cancerous cell lines (HCT8 and A549). High grades of Chinese keemun black teas contained higher contents of total phenolics, flavonoids and ortho-diphenols than lower grades and theaflavin-3,3'-di-gallate could only be detected in high black tea grades (T1 and T2). Intermediate-high keemun black tea grades - C1, C3, T1, and T2 - which also had the highest mean values of TPC, flavonoids, o-diphenols, theaflavin-3-gallate, theaflavin-3'-gallate, Fe2+ chelating ability, and chemical antioxidant activity, presented the highest inhibition of Wistar rat's brain oxidation. No clear differentiation and trend were observed between erythrocyte protection and Chinese black tea grades as results clearly showed that intermediate black tea grades (C3 and C4) protected more the human erythrocytes against mechanical stress. Our study shows that although higher Chinese keemun black tea grades (T1 and T2) presented the highest TPC, flavonoids, and chemical antioxidant activity, these in vitro chemical assays were not translated into higher biological activity.


Assuntos
Antioxidantes/farmacologia , Camellia sinensis , Citotoxinas/farmacologia , Chá/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Análise Multivariada , Fenóis/análise
8.
J Food Sci ; 84(5): 990-1001, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30945309

RESUMO

Red chicory leaves are appreciated sensorially and their constituents contain bioactive properties. The objectives of this study were as follows: to use an experimental design to extract anthocyanins from red chicory in aqueous solution at pH 2.5; to determine the stability of the extracts in relation to temperature and pH; and to evaluate the antioxidant activity and in vitro cytotoxic effect of the lyophilized and purified extracts. The best extraction conditions for the bioactive compounds from red chicory were a temperature of 64.2 °C for 25 min; the anthocyanin content was 73.53 ± 0.13 mg per 100 g fresh weight basis sample. The EC50 (Half maximal effective concentration) value for the antioxidant activity assay in relation to DPPH (2,2-diphenyl-1-picrylhydrazyl) with optimized extract was 0.363, which corresponds to a concentration of 39.171 µmol/L of anthocyanins. The activation energy for the degradation reaction of the anthocyanins from the red chicory extract was 84.88 kJ/mol. The optimized extract, which was rich in anthocyanins, showed chemical and biological antioxidant activity (protection against erythrocyte hemolysis) and inhibited lipid peroxidation in vitro. The Cichorium intybus L. extracts interfered on the levels of reactive oxygen species generation and the crude extract did not present procarcinogenic effect. PRACTICAL APPLICATION: Red chicory is basically consumed as a part of traditional dishes worldwide. Here, we developed a process to extract and purify the anthocyanins from Cichorium intybus leaves and test the extracts in terms of the chemical composition, thermal stability, antioxidant activity, and antiproliferative effects. The anthocyanin-rich extract presented antioxidant activity in chemical and biological assays and low cytotoxicity and cytoprotective effects in relation to HepG2, HCT8, and Caco-2 cell lines. Additionally, the red chicory extract protected human erythrocytes against hemolysis. This extract may be used as a natural colorant/antioxidant in foods.


Assuntos
Antocianinas/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Cichorium intybus/química , Aditivos Alimentares/farmacologia , Extratos Vegetais/farmacologia , Antocianinas/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/metabolismo , Células CACO-2 , Carcinogênese/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Aditivos Alimentares/isolamento & purificação , Células Hep G2 , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Picratos/metabolismo , Extratos Vegetais/química , Folhas de Planta/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA