Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Mais filtros

Base de dados
Intervalo de ano de publicação
Int J Biol Macromol ; 88: 162-70, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27032488


The extraction process of Sphallerocarpus gracilis root polysaccharides (SGRP) was optimized using response surface methodology with two methods [hot-water extraction (HWE) and ultrasonic-assisted extraction (UAE)]. The antioxidant activities of SGRP were determined, and the structural features of the untreated materials (HWE residue and UAE residue) and the extracted polysaccharides were compared by scanning electron microscopy. Results showed that the optimal UAE conditions were extraction temperature of 81°C, extraction time of 1.7h, liquid-solid ratio of 17ml/g, ultrasonic power of 300W and three extraction cycles. The optimal HWE conditions were 93°C extraction temperature, 3.6h extraction time, 21ml/g liquid-solid ratio and three extraction cycles. UAE offered a higher extraction yield with a shorter time, lower temperature and a lower solvent consumption compared with HWE, and the extracted polysaccharides possessed a higher antioxidant capacity. Therefore, UAE could be used as an alternative to conventional HWE for SGRP extraction.

Antioxidantes/isolamento & purificação , Apiaceae/química , Polissacarídeos/isolamento & purificação , Extração em Fase Sólida/métodos , Antioxidantes/química , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Análise Fatorial , Temperatura Alta , Oxirredução , Picratos/antagonistas & inibidores , Picratos/química , Raízes de Plantas/química , Polissacarídeos/química , Extração em Fase Sólida/instrumentação , Sonicação , Água
Molecules ; 20(12): 21442-57, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26633339


An efficient preparative separation method for Sphallerocarpus gracilis stems and leaves polyphenols (SGslP) was established in this study. An X-5 macroporous adsorption resin was selected for the purification of the SGslP, and the polyphenol content of the purified SGslP (PSGslP) was increased 5.11-fold from 8.29% to 42.38% after one treatment run. The chemical composition of the PSGslP was analyzed by HPLC-MS/MS, and the predominant compounds were found to be luteolin-7-glucoside, acacetin-7-acetyglycoside and its isomers. In addition, the PSGslP was evaluated in vitro to determine the DNA damage-protective activity and inhibitory effects of α-amylase and α-glucosidase. The results indicated that the PSGslP exhibited significant protective activities against both ROO• and •OH radical-induced DNA damage. Moreover, the PSGslP exerted a dose-dependent inhibition effect on α-glucosidase but no inhibitory effect on α-amylase. These findings indicate that the Sphallerocarpus gracilis stems and leaves are good natural sources of antioxidants and are potent inhibitors of α-glucosidase activity and are potential anti-diabetic inhibitor.

Apiaceae/química , Dano ao DNA/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Caules de Planta/química , Polifenóis/farmacologia , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/farmacologia , Técnicas In Vitro , Polifenóis/isolamento & purificação
Food Chem ; 170: 394-400, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25306362


The effect of three processing units (blanching, enzyme liquefaction, pasteurisation) on chemical composition and antimicrobial activity of carrot juice essential oil was investigated in this paper. A total of 36 compounds were identified by GC-MS from fresh carrot juice essential oil. The main constituents were carotol (20.20%), sabinene (12.80%), ß-caryophyllene (8.04%) and α-pinene (6.05%). Compared with the oil of fresh juice, blanching and pasteurisation could significantly decrease the components of the juice essential oil, whereas enzyme liquefaction had no considerable effect on the composition of juice essential oil. With regard to the antimicrobial activity, carrot juice essential oil could cause physical damage and morphological alteration on microorganisms, while the three different processing units showed noticeable differences on the species of microorganisms, the minimum inhibitory concentration and minimum bactericidal concentration. Results revealed that the carrot juice essential oil has great potential for application as a natural antimicrobial applied in pharmaceutical and food industries.

Anti-Infecciosos/química , Daucus carota/química , Óleos Voláteis/química , Anti-Infecciosos/farmacologia
Food Chem ; 141(3): 1637-44, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23870871


The effect of three processing units (blanching, enzyme liquefaction, and pasteurisation) on polyphenols and antioxidant activity of carrot juices was investigated. Polyphenols and antioxidant activity of carrot juices varied with different processes. Five polyphenolic acids were identified in fresh carrot juice, and the predominant compound was chlorogenic acid. Compared with fresh carrot juice, blanching and enzyme liquefaction could result in the increase of the total polyphenol content (TPC) and the antioxidant activity in scavenging DPPH free radicals (DPPH) and Fe(2+)-chelating capacity (FC), whereas pasteurisation could result in the decrease of the TPC and the antioxidant activity in DPPH and FC. Meanwhile blanching, enzyme liquefaction, and pasteurisation showed little influence on the antioxidant activity in lipid peroxidation protection. The antioxidant activities in DPPH and FC increased with increasing concentration while no correlation between lipid peroxidation protection and polyphenols concentration. Polyphenols still retained high antioxidant activity after the processes, which have potential health benefits for consumers.

Antioxidantes/química , Bebidas/análise , Daucus carota/química , Manipulação de Alimentos/métodos , Polifenóis/química , Peroxidação de Lipídeos
J Agric Food Chem ; 58(9): 5751-6, 2010 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-20345188


Immature corn grains are becoming increasingly popular as a snack/vegetable, facilitating human consumption in some countries. Of particular interest were their nutritional and functional properties. Therefore, plants at stages M1 (74 DAS), M2 (86 DAS), M3 (98 DAS), and maturity stage (116 DAS), where DAS refers to days after seeding, were investigated for changes of the nutrients, phytochemicals, and antioxidant activity in corn grains during maturation. Results revealed that during maturation of corn grains, the content of reducing sugar and crude protein decreased while starch and total lipids increased (p < 0.05). Total carotenoids first decreased, then increased, and then decreased to minimum at maturity stage. Analysis of the main carotenoid compounds determined by HPLC showed that lutein first increased and then decreased (p < 0.05), whereas the reverse was found for beta-cryptoxanthin. The change in zeaxanthin was consistent with total carotenoids. Total phenolic content decreased; nevertheless, different phenolic fractions varied with various maturation stages. The antioxidant activity determined by DPPH and FRAP assay in total phenolic extracts decreased during maturation, which may explain that antioxidant activity can be attributed to soluble phenolic and total phenolic content.

Antioxidantes/química , Valor Nutritivo , Zea mays/química , Cromatografia Líquida de Alta Pressão , Zea mays/crescimento & desenvolvimento
J Enzyme Inhib Med Chem ; 24(6): 1280-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19912062


Enzyme-assisted water extracts (EWEDL) and ethanol extracts of Du-zhong leaves (EEDL) were evaluated for their antioxidant activities using the DPPH radical-scavenging assay, Fe(2+)-chelating assay, and inhibition ability of the linoleic acid peroxidation assay. In general, the antioxidant activity of Du-zhong leaf extracts increased with increasing concentration. Based on the two extracting methods with different antioxidative reactions, it was shown that the enzyme-assisted water extracting method was more effective for antioxidant extraction from Du-zhong leaves. By HPLC-MS analysis, the main phenolic compounds (geniposidic acid, epicatechin, and chlorogenic acid) identified in EWEDL and EEDL were similar. EWEDL and EEDL had total phenolic contents of 13.84 +/- 0.11 and 14.72 +/- 0.14 mg chlorogenic acid equivalents (CAE) in each gram of extract, respectively. However, there was no positive correlation between total phenolic content and antioxidant activities of EWEDL and EEDL measured by the three different assays.

Antioxidantes/farmacologia , Celulase/metabolismo , Eucommiaceae/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Antioxidantes/química , Antioxidantes/metabolismo , Celulase/química , Eucommiaceae/metabolismo , Depuradores de Radicais Livres/metabolismo , Quelantes de Ferro/metabolismo , Ácido Linoleico/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/fisiologia , Fenóis/química , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Folhas de Planta/metabolismo , Água/química