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1.
Nat Prod Res ; 35(10): 1639-1643, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-31140314

RESUMO

In this study, phytochemical profiling of hydro-alcoholic extract of Ammoides atlantica aerial parts has been carried out using RP-UHPLC-ESI-QTOF-MS in negative ionization mode Chemical characterization was established according to the MS and MS/MS spectra. A total of 66 chemical compounds were detected. Among these, 45 compounds were identified: hydroxycinnamic acid and derivatives (26), hydroxybenzoic acids (4), flavones (11), flavonols (3), and a lignan. Total phenolics (371.57 mg/g) and total flavonoids (41.02 mg/g) contents were also determined. Moreover, the antioxidant activity of A. atlantica extract was also studied by six methods: DPPH (IC50: 23.31 µg/mL), ABTS+ (IC50: 11.31 µg/mL), O2- DMSO alkaline (IC50: 3.19 µg/mL), ferrous ions chelating assays (IC50: 102.35 µg/mL), reducing power (A0.50: 92.70 µg/mL) and CUPRAC (A0.50: 13.56 µg/mL) assays. These results suggest that the antioxidant activity of the hydroalcoholic extract was comparable to common antioxidant additives in most of the tests, representing a good alternative.


Assuntos
Antioxidantes/farmacologia , Apiaceae/química , Flavonoides/farmacologia , Hidroxibenzoatos/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Flavonoides/química , Hidroxibenzoatos/química , Fenóis/análise , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Espectrometria de Massas em Tandem
2.
Nat Prod Res ; 32(8): 982-986, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28875711

RESUMO

In the present work, reversed phase (RP) ultra-high-performance liquid chromatography (UHPLC) coupled to quadrupole-time-of-flight (QTOF) mass spectrometry in tandem has been used for the identification of the main phenolic compounds in the aerial parts of Daucus muricatus. The characterisation of the compounds was carried out taking into account retention time, mass accurate measurements, the generated molecular formulae and fragmentation pattern. These data were contrasted with literature and databases, as well as with those of authentic standards when possible. The proposed method provided tentative identification of 30 phenolic and other polar compounds, including hydroxycinnamic acid derivatives, flavonoids and hydroxybenzoic acid derivatives. As a note, hydroxycinnamic acid derivatives were found to be the most diverse phenolic class of Daucus muricatus.


Assuntos
Apiaceae/química , Cromatografia de Fase Reversa/métodos , Componentes Aéreos da Planta/química , Polifenóis/análise , Polifenóis/química , Espectrometria de Massas em Tandem/métodos , Argélia , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Flavonoides/química , Hidroxibenzoatos/análise , Hidroxibenzoatos/química , Estrutura Molecular , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray/métodos
3.
Food Chem ; 170: 366-77, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25306359

RESUMO

In recent years, agronomical researchers began to cultivate several olive varieties in different regions of Brazil to produce virgin olive oil (VOO). Because there has been no reported data regarding the phenolic profile of the first Brazilian VOO, the aim of this work was to determine phenolic contents of these samples using rapid-resolution liquid chromatography coupled to electrospray ionisation time-of-flight mass spectrometry. 25 VOO samples from Arbequina, Koroneiki, Arbosana, Grappolo, Manzanilla, Coratina, Frantoio and MGS Mariense varieties from three different Brazilian states and two crops were analysed. It was possible to quantify 19 phenolic compounds belonging to different classes. The results indicated that Brazilian VOOs have high total phenolic content because the values were comparable with those from high-quality VOOs produced in other countries. VOOs from Coratina, Arbosana and Grappolo presented the highest total phenolic content. These data will be useful in the development and improvement of Brazilian VOO.


Assuntos
Cromatografia Líquida/métodos , Olea/química , Azeite de Oliva/química , Fenóis/análise , Óleos de Plantas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Brasil
4.
Talanta ; 127: 18-25, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24913852

RESUMO

In the current study, a new approach has been developed for correcting the effect that moisture reduction after virgin olive oil (VOO) filtration exerts on the apparent increase of the secoiridoid content by using an internal standard during extraction. Firstly, two main Spanish varieties (Picual and Hojiblanca) were submitted to industrial filtration of VOOs. Afterwards, the moisture content was determined in unfiltered and filtered VOOs, and liquid-liquid extraction of phenolic compounds was performed using different internal standards. The resulting extracts were analyzed by HPLC-ESI-TOF/MS, in order to gain maximum information concerning the phenolic profiles of the samples under study. The reduction effect of filtration on the moisture content, phenolic alcohols, and flavones was confirmed at the industrial scale. Oleuropein was chosen as internal standard and, for the first time, the apparent increase of secoiridoids in filtered VOO was corrected, using a correction coefficient (Cc) calculated from the variation of internal standard area in filtered and unfiltered VOO during extraction. This approach gave the real concentration of secoiridoids in filtered VOO, and clarified the effect of the filtration step on the phenolic fraction. This finding is of great importance for future studies that seek to quantify phenolic compounds in VOOs.

5.
J Agric Food Chem ; 61(22): 5179-88, 2013 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-23656613

RESUMO

This review describes the olive oil production process to obtain extra virgin olive oil (EVOO) enriched in polyphenol and byproducts generated as sources of antioxidants. EVOO is obtained exclusively by mechanical and physical processes including collecting, washing, and crushing of olives, malaxation of olive paste, centrifugation, storage, and filtration. The effect of each step is discussed to minimize losses of polyphenols from large quantities of wastes. Phenolic compounds including phenolic acids, alcohols, secoiridoids, lignans, and flavonoids are characterized in olive oil mill wastewater, olive pomace, storage byproducts, and filter cake. Different industrial pilot plant processes are developed to recover phenolic compounds from olive oil byproducts with antioxidant and bioactive properties. The technological information compiled in this review will help olive oil producers to improve EVOO quality and establish new processes to obtain valuable extracts enriched in polyphenols from byproducts with food ingredient applications.


Assuntos
Antioxidantes/análise , Manipulação de Alimentos , Frutas/química , Resíduos Industriais/análise , Olea/química , Óleos de Plantas/química , Polifenóis/análise , Antioxidantes/economia , Antioxidantes/isolamento & purificação , Produtos Agrícolas/química , Suplementos Nutricionais/economia , Conservantes de Alimentos/análise , Conservantes de Alimentos/economia , Conservantes de Alimentos/isolamento & purificação , Qualidade dos Alimentos , Alimentos Fortificados/economia , Indústria de Processamento de Alimentos/economia , Resíduos Industriais/economia , Azeite de Oliva , Extratos Vegetais/química , Extratos Vegetais/economia , Extratos Vegetais/isolamento & purificação , Polifenóis/economia , Polifenóis/isolamento & purificação
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