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1.
ScientificWorldJournal ; 2012: 142983, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23304076

RESUMO

A "novel" protocol is presented for easy and reliable estimation of soluble hydroxycinnamate levels in Cichorium intybus L. leaf tissue in large-scale experiments. Samples were standardized by punching 6 discs per leaf, and hydroxycinnamates were extracted by submerging the discs in 80% ethanol with 5% acetic acid for at least 48 h in the darkness at 4°C. Residual dry mass of the discs was used for a posteriori correction of compound levels. Chlorophyll was eliminated by chloroform, and the aqueous phases were transferred to microplates, dried, and dissolved in 50% methanol for HPLC analysis and storage. An HPLC program of 8 min was developed for the analysis of the extracts. Comparisons with extractions of liquid nitrogen powders indicated that the novel extraction method was reliable. No degradation of the major hydroxycinnamates-caftaric, chlorogenic, and chicoric acids-was observed, during maceration at ambient temperatures, or after storage for 1 year.


Assuntos
Química Farmacêutica/tendências , Cichorium intybus , Ácidos Cumáricos/análise , Folhas de Planta , Asteraceae , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Ácidos Cumáricos/química , Espectrometria de Massas/métodos
2.
J Ethnopharmacol ; 89(1): 143-50, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14522446

RESUMO

In an infection, polymorphonuclear neutrophils (PMN) become activated and they produce oxidizing compounds and elastase in the extracellular medium. Alpha-1-proteinase inhibitor (alpha1PI), a protease inhibitor which is inactivated by oxidants, is the main endogenous inhibitor of elastase helping to limit excessive elastase activity. This study evaluates the ability of a plant extract, Cola nitida nuts, to protect alpha1PI from inactivation by oxidizing compounds as reactive oxygen species. On the one hand, we have evaluated the direct effect of cola nut extract on neutrophil elastase, and on the H(2)O(2) and myeloperoxidase (MPO)-H(2)O(2) system via cell-free systems. Results showed that cola nut extract scavenges H(2)O(2) and therefore protects alpha1PI from HOCl which is produced from the MPO-H(2)O(2) system. Experiments also showed that cola extract has the capacity to limit elastase activity. On the other hand, we have worked on cellular systems including isolated PMN with the aim to study the effect of cola extract on PMN metabolism. PMN were stimulated with PMA, calcium ionophore or fMLP. Each stimulant possesses its own stimulation pathway. According to the inhibitory concentration obtained at 50%, the results on cellular systems led to the conclusion that cola extract can reduce elastase liberation from PMN. It can then be concluded that cola nut extract can protect alpha1PI from inactivation, and has an effect both on elastase liberation and elastase activity. The cola nut extract effect is rather biased towards a reduction in elastase release, thus limiting the injurious effects caused by this enzyme.


Assuntos
Cola , Elastase de Leucócito/antagonistas & inibidores , N-Formilmetionina Leucil-Fenilalanina/análogos & derivados , alfa 1-Antitripsina/metabolismo , Cafeína , Calcimicina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Ativadores de Enzimas/farmacologia , Sequestradores de Radicais Livres/farmacologia , Humanos , Peróxido de Hidrogênio/metabolismo , Técnicas In Vitro , Ionóforos/farmacologia , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/citologia , Neutrófilos/metabolismo , Nozes , Extratos Vegetais/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Fosfolipases Tipo C/metabolismo
3.
Nahrung ; 47(3): 191-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12866623

RESUMO

Crataegus (Hawthorn) has long been used as a folk medicine and is widely utilized in pharmaceutical preparations mainly because of its neuro- and cardiosedative actions and its low toxicity. The pharmacological effects of Crataegus have mainly been attributed to the polyphenolic contents. In this study, the production of polyphenols by ten-year-old Crataegus monogyna calli was studied in relation to growth variation and antioxidant capacity within a subculture period. Assays based on the Trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP) and stability in oil-in-water emulsion were used to characterize the antioxidant actions of the callus cultures. High TEAC (3.66 micromol/g dry weight) and FRAP (208.19 micromol Fe2+/g dry weight) values were observed when maximal growth was reached(days 30-35), and this seemed to be influenced by optimum total phenol (47.40 mg/g dry weight), proanthocyanidin (20.81 mg/g dry weight), flavonoid (7.01 mg/g dry weight), anthocyanin (6.18 mg/g dry weight), (-)-epicatechin (1.77 mgl/g dry weight), procyanidin B2 (3.97 mg/g dry weight), and chlorogenic acid (1.11 mg/g dry weight) production during that period. The TEAC values were strongly associated with total flavonoids and to a lesser extent with total phenols, anthocyanins and total proanthocyanidins. The FRAP antioxidant values correlated to total phenols, proanthocyanidins and flavonoids, respectively. The polyphenolic rich calli were as effective as butylated hydroxytoluene (BHT) in preventing hydroperoxide and conjugated diene formation in a 30% oil-in-water emulsion prepared with stripped sunflower oil, during 7days storage at 30 degrees C. Crataegus monogyna cell culture represents an important alternative source for natural antioxidants.


Assuntos
Antioxidantes/farmacologia , Biflavonoides , Catequina , Flavonoides , Fenóis/farmacologia , Extratos Vegetais/química , Polímeros/farmacologia , Proantocianidinas , Antioxidantes/análise , Células Cultivadas , Crataegus , Oxirredução , Fenóis/análise , Extratos Vegetais/farmacologia , Polímeros/análise , Polifenóis , Relação Estrutura-Atividade
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