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1.
Pharmacogn Mag ; 13(Suppl 3): S424-S429, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29142394

RESUMO

BACKGROUND: Opuntia ficus-indica (OFI) (L.) Mill. (Cactaceae), a plant widespread in dry regions of the world, shows interesting biological activities (cicatrizant, antiulcer, anti-inflammatory, and hypolipidemic) and is widely used in traditional medicine. OBJECTIVES: Phytochemical analysis and antispasmodic effect of wild OFI cladodes were carried out. MATERIAL AND METHODS: Polyphenols and Vitamin E occurrence, in antioxidant pool of OFI cladodes, were quantified by high-performance liquid chromatography. The antispasmodic effect of OFI cladodes was assessed in isolated rabbit smooth muscle tissues. The experiments were carried out with preparations of rabbit jejunum and uterus with the spontaneous contractile activity, to evaluate the effect of cumulative concentrations of the extract on basal tone, amplitude, and frequency of contractions. RESULTS: Catechin, quercetin, kaempferol, isorhamnetin and chlorogenic, ferulic, and p-coumaric acid were identified. α-, ß-, and γ-tocopherols have been highlighted and α-tocopherol is the major component. OFI cladodes contain significant amount of polyphenols and tocopherols that are effective radical scavengers and inhibited ethanol 1,1-diphenyl-2-picrylhydrazyl formation by 50%. OFI cladodes caused a light inhibition of amplitude and frequency of spontaneous contractions and a marked decrease in muscle basal tone of rabbit jejunum preparations. On spontaneously contracting uterus preparations, the addition of increasing concentrations of cladode extract caused uterine muscle relaxation. CONCLUSION: The contraction of smooth muscle preparations depends on an increase in cytoplasmic free calcium ion concentration, which activates the contractile elements. The flavonoids may suppress the contractility of smooth myocytes, by an inhibition of availability of Ca2+ for muscle contraction. SUMMARY: Opuntia ficus-indica (OFI) cladodes contain significant amount of polyphenols and tocopherols that are effective radical scavengers and inhibited ethanol 1,1-diphenyl-2-picrylhydrazyl formation by 50%Polyphenols and Vitamin E complex occurrence in OFI cladodes were characterized by high-performance liquid chromatographyOFI cladodes exhibited significative antispasmodic activity. The antispasmodic effect was assessed in isolated rabbit smooth muscle tissues. The experiments were carried out with preparations of rabbit jejunum and uterus with the spontaneous contractile activity, to evaluate the effect of cumulative concentrations of the extract on basal tone, amplitude, and frequency of contractions. Abbreviations used: OFI: Opuntia ficus-indica, DPPH: Ethanol 1,1-diphenyl-2-picrylhydrazyl.

2.
Phytother Res ; 30(8): 1298-307, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27076277

RESUMO

The aim of this study was to characterize the polyphenolic compounds and antioxidant activity of cold-pressed seed oil from Finola cultivar of industrial hemp (Cannabis sativa L.). Several methodologies have been employed to evaluate the in vitro antioxidant activity of Finola hempseed oil (FHSO) and both lipophilic (LF) and hydrophilic fractions (HF). The qualitative and quantitative composition of the phenolic fraction of FHSO was performed by HPLC analyses. From the results is evident that FHSO has high antioxidative activity, as measured by DPPH radical (146.76 mmol of TE/100 g oil), inhibited ß-carotene bleaching, quenched a chemically generated peroxyl radical in vitro and showed high ferrous ion chelating activity. Reactivity towards 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical cation and ferric-reducing antioxidant power values were 695.2 µmol of TE/100g oil and 3690.6 µmol of TE/100 g oil respectively. FHSO contains a significant amount of phenolic compounds of which 2780.4 mg of quercetin equivalent/100 g of total flavonoids. The whole oil showed higher antioxidant activity compared with LF and HF. Our findings indicate that the significant antioxidant properties shown from Finola seed oil might generally depend on the phenolic compounds, especially flavonoids, such as flavanones, flavonols, flavanols and isoflavones. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Cannabis/química , Flavonoides/farmacologia , Polifenóis/farmacologia , Sementes/química , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Polifenóis/análise
3.
J Sep Sci ; 30(14): 2305-10, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17688301

RESUMO

Increasing demand for gasoline, changing regulations concerning the reduction of environmental impact, and new refining technologies have led to the refinement of its composition. Nowadays, gasoline is a complex mixture of different fractions deriving from processes of reforming, cracking, isomerization, and alkylation, with the addition of both oxygenated compounds and butanes. There are regulations governing the mixing of various fractions and it is necessary to analyse the composition of these fractions to ensure that the final composition of commercial gasoline satisfies the required specifications. Moreover, analysis of the composition of each fraction enables the technological process of the fraction examined to be modified as appropriate. In this work some reformed gasolines were analysed by multidimensional gas chromatography. This technique allows good separation of the hydrocarbon types in a single analysis and gives the carbon number distribution within each hydrocarbon type.

4.
Ann Chim ; 96(9-10): 553-60, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17172208

RESUMO

In order to cope with the increasing demand for gasoline and the need to reduce environmental impact for sustainable development, refineries have installed refining technology by introducing cracking, reforming, isomerization and alkylation. The standard EN 228: 2004 outlines the specification that gasoline, deriving from the blend of several fractions, must have for use in modem piston engines. Naphtha is one of the products from distilling crude oil that can be used as starting material in the reforming process whose derivatives, which are a fraction of gasoline, depend on the composition of the naphtha. Knowledge of the naphtha composition thus enables to provide the final composition of the products of reforming, the efficiency of the plant and also provides information about the crude oil used. In this paper some naphtha samples were analysed by multidimensional gas chromatography. This technique allows in a single analysis a good separation of the hydrocarbon types and within each hydrocarbon type a good carbon number separation.


Assuntos
Alcanos/química , Cromatografia Gasosa/métodos , Alcenos/análise , Cromatografia Gasosa/instrumentação , Hidrocarbonetos Aromáticos/análise , Óleos/análise , Parafina/análise
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