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1.
J Chromatogr Sci ; 60(5): 486-492, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34528093

RESUMO

A novel and reliable microextraction technique was used for the fast determination of benzene, toluene, ethylbenzene and xylenes (BTEX) from contaminated water without any extra steps for the preparation or extraction of the aqueous sample. Vacuum-assisted-total vaporization-solid-phase microextraction (SPME) eliminated one of the partitioning steps in conventional headspace SPME and caused an increase in the sensitivity and speed of the method. A home-made graphene oxide/3-aminopropyl-triethoxysilane nanocomposite SPME fiber was synthesized and used as the extraction phase for efficient extraction. Several crucial parameters were optimized, such as the vaporization time and temperature, extraction time and desorption conditions. At the optimum experimental conditions, a linear wide range calibration curve over a wide range of 1-5,000 ng mL-1 and a relative standard deviation (n = 6) of 6.6-7.3% were obtained. The result of the determination of BTEX as a human health risk from real samples, using the proposed method, revealed an acceptable agreement with a valid method.


Assuntos
Benzeno , Xilenos , Derivados de Benzeno , Humanos , Microextração em Fase Sólida/métodos , Tolueno , Volatilização , Água
2.
Nat Prod Res ; 36(10): 2692-2705, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33908327

RESUMO

Eremurus persicus (Jaub. & Spach) Boiss. commonly known as "Serish" is a valuable ornamental plant with culinary uses and also utilized in traditional medicine for treating Gastrointestinal diseases. This comprehensive study was performed to investigate the pharmacological and biological effects of E. persicus and the compounds identified and isolated from it in order to encourage researchers to study it further. Despite the few number of studies on the ethnopharmacology of the plant E. persicus, however studies conducted on either crude extracts, solvent fractions or isolated pure compounds from E. persicus a varied range of biological effects comprising antibacterial, anti-fungal, anti-diabetic and etc. have reported. Phytochemical analysis of different parts of E. persicus unveiled 52 phytochemicals. However, the toxicity of this plant and its ethnopharmacological claims should be thoroughly investigated.


Assuntos
Botânica , Extratos Vegetais , Etnofarmacologia , Irã (Geográfico) , Medicina Tradicional , Compostos Fitoquímicos , Fitoterapia , Extratos Vegetais/química
3.
Inflammopharmacology ; 29(5): 1279-1290, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34410540

RESUMO

Mesalazine, also known as 5-aminosalicylic acid (5-ASA), is a synthetic drug from the family of nonsteroidal anti-inflammatory drugs (NSAIDs) used for inflammatory diseases of the gastrointestinal tract. However, 5-ASA has also been used for various other diseases due to its pharmacological effects, but they are usually scattered across various publications, which may limit further research and clinical use of this drug. This review is a summary of published information on the biological and pharmacological effects of 5-ASA with the aim of identifying its anti-oxidant role and medicinal use. 5-ASA data have been collected from 1987 to February 2021 using major databases such as Web of Science, PubMed, Elsevier, Wiley Online Library, Springer, Google Scholar, etc. According to research, the pharmacological and biological effects of 5-ASA include treatment of inflammatory bowel disease, and anti-oxidant, anti-inflammatory, antibacterial, antifungal, anticancer, anti-amyloid, gastric protection (gastroprotective), and antidiverticulosis properties. Numerous pharmacological studies have shown that 5-ASA is an anti-oxidant and anti-ulcer compound with high therapeutic potential that, if the appropriate dose is discovered, its chemical structure changes and its effectiveness is optimized, 5-ASA has been used experimentally for other diseases.


Assuntos
Antiulcerosos/farmacologia , Antioxidantes/farmacologia , Mesalamina/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Humanos
4.
Inflammopharmacology ; 29(5): 1503-1518, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34435283

RESUMO

This study aimed to investigate the antioxidant and protective effect of E. persicus leaf hydroalcoholic extract (EPE) in preventing gastric ulcers induced by ethanol in rats. Wistar rats weighing 180-220 g were randomly divided into five groups. These groups included negative control (normal) group, positive control (ethanolic) group, comparative control (ranitidine recipient) group, group recipient the dose of 250 mg/kg plant extract, and group recipient the dose of 500 mg/kg plant extract. One hour after gavage of the drug and extract, the gastric ulcer was induced by feeding 1 ml of 96% ethanol to each animal except the rats of the negative control group. After one hour, the rats were killed, and their stomachs were separated. Then, the gastric Ulcer index (UI), pH, oxidative stress parameters, and histopathological changes in the stomach of all groups were measured. Pre-treatment of ethanol-induced rats with the EPE reduced (P < 0.05) the ulcer index and gastric juice pH, compared to ethanolic group rats. Furthermore, pre-treatment with EPE at a dose-dependent manner, alleviated the gastric oxidative stress injury in rats through increase the activity of CAT, tissue NO· and GSH levels. EPE also was able to decrease the levels of ROS, MDA, PCO and serum NO·. According to the results, it can be concluded that pre-treatment with EPE prevents the formation of gastric ulcers caused by ethanol, which can be attributed to the antioxidant activity of plant polyphenols compounds.


Assuntos
Antiulcerosos/farmacologia , Antioxidantes/farmacologia , Asphodelaceae/química , Extratos Vegetais/farmacologia , Animais , Antiulcerosos/administração & dosagem , Antiulcerosos/isolamento & purificação , Antioxidantes/administração & dosagem , Antioxidantes/isolamento & purificação , Relação Dose-Resposta a Droga , Etanol/toxicidade , Masculino , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Folhas de Planta , Polifenóis/isolamento & purificação , Polifenóis/farmacologia , Ranitidina/farmacologia , Ratos , Ratos Wistar , Úlcera Gástrica/prevenção & controle
5.
Eur J Pharmacol ; 888: 173573, 2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-32956646

RESUMO

Gastric ulcer is a frequent gastrointestinal tract (GIT) disorder that affects about 10% of the world population. Drug candidates that can provide high efficacy and low toxicity are needed value for the prevention and treatment of gastric ulcers. The present study aimed to assess the protective effect of mesalazine against ethanol-induced gastric mucosal injury in rats. The rats were divided into five groups, normal, ethanolic, standard (recipient ranitidine 50 mg/kg), experimental groups 1, 2 (receive mesalazine at doses of 50 and 100, respectively). The protective effect of mesalazine was evaluated by the ulcer index, histological examinations, measurement of oxidative stress parameters, antioxidant systems, and some gastric mucosal protection factors. Pre-treatment of rats with doses of 50 and 100 mg/kg Mesalazine (5-ASA) in experimental groups 1 and 2 increased the pH of gastric juice and reduced the gastric ulcer index compared to the ethanolic group. Also, the results indicated that mesalazine, reduced the tissue reactive oxygen species (ROS), malondialdehyde (MDA), and protein carbonyl (PCO) levels, serum nitric oxide (NO), and increased the level of tissue NO and glutathione (GSH) and activity of Catalase (CAT), Based on these results, it can be concluded that mesalazine strengthens the antioxidant defense system of gastric mucosal cells during oxidative damage caused by ethanol.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Antiulcerosos/uso terapêutico , Etanol/toxicidade , Mesalamina/uso terapêutico , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/prevenção & controle , Animais , Masculino , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar , Úlcera Gástrica/metabolismo
6.
Environ Sci Pollut Res Int ; 27(29): 36306-36315, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32556985

RESUMO

Release of analytes from their native matrix and diffusion into the gas phase is the rate-limiting step for the sampling of volatiles in complex solid samples. This limitation is more serious in the solvent-less and solvent-free microextraction sampling strategies. In this research, a three-stage reinforced sampling strategy including high-pressure/sonication/low-pressure was introduced for fast and efficient release of analytes in soil samples. For this purpose, a novel ultrasound-assisted pressure-regulated solid-phase microextraction (UA-PR-SPME) device was developed. It was coupled with gas chromatography-flame ionization detection (GC-FID) and carried out for the determination of benzene, toluene, ethylbenzene, and xylenes (BTEX, as the model analytes) in complex solid samples. Graphene oxide/3-aminopropyltriethoxysilane (GO-APTES) nanocomposite was synthesized and used as the SPME fiber coating. Under optimal conditions, the limits of detection (LODs) were obtained 0.1-0.4 ng/g. The calibration curves were linear over the range of 2.4-5000 ng/g. Relative standard deviations (RSDs%) were calculated 5.1-7.0% (n = 6). The developed technique was employed for the analysis of BTEX in contaminated soil samples.


Assuntos
Poluentes Ambientais , Benzeno/análise , Derivados de Benzeno/análise , Solo , Microextração em Fase Sólida , Tolueno/análise , Xilenos/análise
7.
Talanta ; 212: 120809, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32113525

RESUMO

This paper describes how a novel and reliable alternative approach was developed for conventional solid-phase microextraction (SPME) sampling by total-vaporization of a sample under vacuum conditions. SPME sampling consists two stages of the equilibrium process, which take place between the sample/headspace and the headspace/fiber coating. In the total-vaporization SPME (TV-SPME) strategy, the first stage is omitted and analytes are directly partitioned between the headspace and fiber coating. In this research, the TV-SPME strategy was implemented by the extraction of PAHs from aqueous media, using a polydimethylsiloxane (PDMS) coated SPME fiber. The most important variables were investigated and optimized. Optimal conditions were obtained at an extraction temperature of 55 °C, a vaporization time of 25 min, and a sample volume of 100 µL. To achieve higher sensitivities in shorter times, the TV-SPME setup was coupled with the VA-SPME system, which resulted in a much lower extraction temperature and time, in comparison with the conventional TV-SPME method. Under optimal experimental conditions, the calibration curves were linear across the area of 0.015-2 µg mL-1 (R2 > 0.996). The limits of detection (LODs) were obtained in the range of 0.3-5 ng mL-1, and the relative standard deviations (RSDs, n = 6) were 6.1-7.5%. The developed vacuum-assisted total-vaporization SPME (VA-TV-SPME) technique, was coupled with GC-FID and successfully utilized for the determination of polycyclic aromatic hydrocarbons (PAHs) in river water samples. The data obtained was statistically in accordance with that achieved employing a validated approved method.

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