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1.
Ultrastruct Pathol ; 45(2): 102-111, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33688798

RESUMO

Pistacia atlantica Desf. (Atlas Pistachio) is an Anacardiaceae tree traditionally used in Tunisia for the treatment of ophthalmic, stomatitis, and digestive tract diseases. In the present study, the Pistacia atlantica Desf. roots extract (PR) was phytochemically analyzed, for the first time, by LC-ESI-MS for phenolic and flavonoid contents, in vitro tested for its potential antioxidant activity based on the 2.2-diphenyl-1-picrylhydrazyl (DPPH) and the reduced power essays (FRAP), and in vivo tested for its ability to shield against ethanol-induced gastric ulcer in mice. The LC-ESI-MS analysis proved the identification of 12 compounds, including Quinic, Gallic, and Protocatechuic, as major phenolic acids and high levels of flavonoids, such as Catechin, Epicatechin, and Cirsiliol. PR also exhibited a mild in vitro antioxidant activity when compared with ascorbic acid. In vivo pretreatment of ethanol-ulcerated mice with PR doses 50 mg/kg and 100 mg/kg body weight (b.w) significantly reduced (P< .05) gastric lesions at a rate of 20.10% and a rate of 40.90%, respectively, when compared with 60.70% rate of sucralfate (50 mg/kg b.w) evidenced by a dose-dependent manner increase in the gastric mucosa enzymatic (SOD, CAT, GPx) antioxidant levels, the decline of the lipid peroxidation, and the preservation of normal gastric superficial epithelium. The underlying mechanism of PR antiulcerogenic activity could be due to a synergistic effect of phenolic acids and flavonoid contents which enhances the gastric antioxidant defense system.Abbreviations: BHT: butylated hydroxytoluene, b.w: body weight, CAT: catalase, DPPH:1-Diphenyl-2-picrylhydrazyl, DW: dry weight, EtOH: ethanol, FRAP: Ferric reducing antioxidant power, GAE: gallic acid equivalents, GPx: Glutathione peroxidase, QE: quercetin equivalents, LC-ESI-MS: Liquid chromatography-Electrospray Ionization-Tandem Mass Spectrometry, MDA: malondialdehyde, PR: Pistacia root, TBA: thiobarbituric acid reagent, TBARS: thiobarbituric acid reactive substances, TCA: trichloroacetic acid, SOD: Superoxide dismutase.


Assuntos
Pistacia , Úlcera Gástrica , Animais , Antioxidantes/farmacologia , Cromatografia Líquida , Camundongos , Extratos Vegetais/farmacologia , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/prevenção & controle
2.
Sci Rep ; 10(1): 11048, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32632234

RESUMO

In this work, spent coffee grounds (SCG) were treated using sulfuric acid hydrolysis in order to isolate the sulfuric acid lignin (SAL). The reactivity of SAL was improved through phenolation and acetylation. Spectroscopic analysis showed that the isolated lignin is composed of GHS type and it was characterized by a high amount of (C-C) and ß-O-4 bonds. The thermal analysis showed that the phenolated sulfuric acid lignin (Ph-SAL) present higher thermal stability compared to SAL and acetylated sulfuric acid lignin. In addition, the phenolic hydroxyl group content increases from 2.99 to 9.49 mmol/g after phenolation. Moreover, a methylene blue (MB) adsorption test was established in order to find out the sorption capacity of different samples. The study showed that the adsorbed amount of dye increase after the chemical modification of SAL, especially after phenolation. The removal efficiency was enhanced after modification to reach 99.62% for Ph-SAL. The evaluation of the adsorption experimental data with the theoretical models of Langmuir and Freundlich showed that the best fitting was expressed by the Langmuir model for all samples. Finally, this study showed that lignin isolated from SCG can be simply and easily chemical modified and exhibits excellent adsorption ability towards cationic dyes (MB) in aqueous solutions. As a renewable, low-cost, and natural biomass material, lignin from SCG shows a promising practical and economical application of biomass in the field of wastewater purification.

3.
Biotechnol Rep (Amst) ; 26: e00442, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32181152

RESUMO

Ultrasound pretreatment with different times (0, 4, 8, 10 min) on olive paste previous malaxation of olive oil extraction along with depitting and water application procedures were studied. The effects of these procedures on oil yield, quality parameters and oxidative stability have been studied. Therefore, the olive oil yield increase with increasing time of ultrasound treatment. On the other hand, the application of ultrasound did not adversely affect the quality characteristics, as well as the antioxidant activity, when comparing with untreated paste. Furthermore, the oxidative stability data, we can conclude that ultrasound treatment can affect the olive oil oxidative stability. This study could provide useful information for industry to produce olive oil with high yield and quality.

4.
Chemistry ; 23(12): 2788-2791, 2017 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-28093829

RESUMO

Several reported methods allow access to α-arylated selenophenes, whereas the synthesis of ß-arylated selenophenes remains very challenging. Here, the Pd-catalysed coupling of benzenesulfonyl chlorides with selenophenes affording regiospecific ß-arylated selenophenes is reported. The reaction proceeds with easily accessible catalyst, base and substrates, and tolerates a variety of substituents both on the benzene and selenophene moieties. This transformation allows the programmed synthesis of polyarylated selenophenes with potential applications in pharmaceutical and materials chemistry, as the installation of aryl groups at the desired positions can be achieved.

5.
J Oleo Sci ; 62(12): 981-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24292349

RESUMO

Refined olive oil has been analyzed in order to evaluate the influence of storage time on their quality after enrichment with chlorophyll pigments and squalene. At the end of the storage, chlorophyll pigments decomposed for more than 90%, while, carotene pigment loss was lower showing up to 75% in all oil samples stored at 20°C and 50°C. The reduction of total phenolic compounds exhibited similar degradation profiles, reducing by 81% for enriched refined olive oil stored at 20°C and 50°C after six months. For all studied samples, squalene content decreased significantly (p< 0.05) only after four months of storage. Oils with added pure squalene had the lower peroxide values (52 meq O2 · kg(-1)) at the end of storage at 20°C. After six months of storage the oxidative stability increased to 1 h 28 min and 2 h 06 min for refined olive oil stored at 20°C enriched with chlorophyll + squalene and only by squalene, respectively. Therefore, squalene supplemented with 800 mg · kg(-1) exhibited favorable antioxidant effects and is preferable for effectively avoiding oxidation. This study could provide useful information for industry to produce high-stability vegetable oil.


Assuntos
Antioxidantes , Clorofila , Aditivos Alimentares , Armazenamento de Alimentos , Óleos de Plantas , Esqualeno , Azeite de Oliva , Oxirredução , Óleos de Plantas/química , Temperatura , Fatores de Tempo
6.
J Sci Food Agric ; 93(5): 1242-8, 2013 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22936570

RESUMO

BACKGROUND: The characterisation of virgin olive oils from two Tunisian cultivars, growing in the Tataouin zone, namely Jemri-Bouchouka, a rare olive cultivar, and Chemlali-Tataouin, was carried out. Several analytical parameters were evaluated; these include quality index, fatty acids, phenolic, chlorophyll, carotenoid, squalene, α-tocopherol compositions and oxidative stability. RESULTS: Jemri-Bouchouka olive oil had the highest value of oleic acid (74.50%) while Chemlali-Tataouin olive oil had the highest value of oleic acid (69.39 %) and also was characterized by a high percentage of palmitic acid (14.75 %) which makes this oil freeze at a low temperature [corrected]. On the other hand, Jemri-Bouchouka oil was characterised by a low phenolic and α-tocopherol content (267.72 mg GAE kg⁻¹ and 278.34 mg kg⁻¹, respectively). Ten phenolic compounds were identified. The main phenols found in the two olive oils were oleuropein aglycon and pinoresinol. All phenolic compounds showed significant correlations with oxidative stability. CONCLUSION: The analytical parameters of virgin olive oil that were determined in this study were greatly influenced by cultivar.


Assuntos
Antioxidantes/análise , Ácidos Graxos/análise , Qualidade dos Alimentos , Frutas/química , Olea/química , Fenóis/análise , Óleos de Plantas/química , Antioxidantes/metabolismo , Ácidos Graxos/metabolismo , Armazenamento de Alimentos , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Furanos/análise , Furanos/metabolismo , Concentração de Íons de Hidrogênio , Glucosídeos Iridoides , Iridoides , Lignanas/análise , Lignanas/metabolismo , Peróxidos Lipídicos/análise , Olea/crescimento & desenvolvimento , Olea/metabolismo , Ácido Oleico/análise , Ácido Oleico/metabolismo , Azeite de Oliva , Oxirredução , Ácido Palmítico/análise , Ácido Palmítico/metabolismo , Fenóis/metabolismo , Pigmentos Biológicos/análise , Pigmentos Biológicos/metabolismo , Piranos/análise , Piranos/metabolismo , Especificidade da Espécie , Temperatura de Transição , Tunísia , alfa-Tocoferol/análise , alfa-Tocoferol/metabolismo
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