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1.
J Sep Sci ; 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31944578

RESUMO

A novel, simple, and sensitive method has been developed for simultaneous determination of 14 heterocyclic aromatic amines in meat product using solid-phase extraction combined with ultrahigh-performance supercritical fluid chromatography coupled to tandem quadrupole mass spectrometry. The analytes could be separated within 7 min and identified using their retention times and mass. The developed method was validated based on the linearity, limits of quantification, precision, and accuracy. The recovery ranged from 52.3 to 97.5% with an acceptable standard deviation, which is not higher than 6%. The limits of quantitation ranged from 0.03 to 0.17 µg/kg. The selectivity and sensitivity were satisfactory in multiple reaction monitoring mode. The method was applied to commercial meat products, and the results demonstrated that the novel method has potential for the analysis of the targets in food matrices. This is the first work reporting the simultaneous quantification of 14 heterocyclic aromatic amines by means of ultrahigh-performance supercritical fluid chromatography coupled to tandem quadrupole mass spectrometry.

2.
Molecules ; 25(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861927

RESUMO

Anwuligan, a natural 2,3-dibenzylbutane lignan from the nutmeg mace of Myristica fragans, has been proved to possess a broad range of pharmacological effects. A rapid, simple, and sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been established and successfully applied to the study of pharmacokinetics and tissue distribution of anwuligan after intravenous or intragastric administration. Sample preparation was carried out through a liquid-liquid extraction method with ethyl acetate as the extraction reagent. Arctigenin was used as the internal standard (IS). A gradient program was employed with a mobile phase consisting of 0.1% formic acid aqueous solution and acetonitrile. The mass spectrometer was operated in a positive ionization mode with multiple reaction monitoring. The transitions for quantification were m/z 329.0→205.0 for anwuligan and m/z 373.0→137.0 for IS, respectively. Calibration curves were linear over the ranges of 0.5-2000 ng/mL for both plasma samples and tissue samples (r > 0.996). The absolute bioavailability is 16.2%, which represented the existing of the obvious first-pass effect. An enterohepatic circulation was found after the intragastric administration. Anwuligan could be distributed rapidly and widely in different tissues and maintained a high concentration in the liver. The developed and validated LC-MS/MS method and the pharmacokinetic study of anwuligan would provide reference for the future investigation of the preclinical safety of anwuligan as a candidate drug.

3.
Molecules ; 24(19)2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31597294

RESUMO

Doxorubicin (DOX) is an effective anti-tumor drug widely used in clinics. Hernandezine (HER), isolated from a Chinese medicinal herb, has a selective inhibitory effect on DOX multidrug resistance, making DOX more effective in treating cancer. The aim of this study was to investigate the effect of the interaction of HER and DOX on pharmacokinetics. Male Sparague-Dawley rats were randomly divided into three groups: a single DOX group, a single HER group, and a combination group. Plasma concentrations of DOX and HER were determined by the LC-MS/MS method at specified time points after administration, and the main pharmacokinetic parameters were estimated. The results showed that there were significant differences in the Cmax and AUC0-∞ of DOX in the single drug group and combined drug group, indicating that HER could improve the absorption of DOX. However, DOX in combination, in turn, reduced the free drug concentration of HER, possibly because DOX enhanced the HER drug-protein binding effect. The results could be used as clinical guidance for DOX and HER to avoid adverse reactions.

4.
Crit Rev Anal Chem ; : 1-32, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31646873

RESUMO

Cephalosporins, one of the classic ß-lactam antibiotics, has been widely concerned by global population as the most commonly used broad-spectrum antibiotic. Serious health hazards are possible to be posed by quality control problems caused by its unstable structure, as well as food and environmental pollution introduced by improper use. Given the reasons above, the sensitive and valid methods for monitor and determination of cephalosporins in different matrices are urgently required. This review aims to provide a comprehensive overview on the current status of the pretreatment and analysis methods of cephalosporins in bulk drug, pharmaceutics, animal-derived foodstuffs including eggs, milk, meat, environment samples, and biological samples. Pretreatment methods including simple steps (protein precipitation, centrifugation, filtration), liquid-liquid extraction, solid phase extraction, QuECHERS, and detection methods covering LC, LC-MS/MS, voltammetric sensor, capillary electrophoresis spectroscopy, biological methods from January 2005 to October 2018 are updated, elaborated and compared here. Moreover, advanced materials and prospects for development are discussed. Highlights Determination of cephalosporins in different newly found matrix are represented. Comparisons between different mass analyzers and progress in HRMS methods are in detailed. Optimization of experimental conditions are discussed. Newly emerged eco-friendly methods are introduced.

5.
Molecules ; 24(17)2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31480657

RESUMO

Alnustone, a nonphenolic diarylheptanoid, first isolated from Alnus pendula (Betulaceae), has recently received a great deal of attention due to its various beneficial pharmacological effects. However, its pharmacokinetic profile in vivo remains unclear. The purpose of this study is to establish a fast and sensitive quantification method of alnustone using liquid chromatography tandem mass spectrometry (LC-MS/MS) and evaluate the pharmacokinetic and tissue distribution profiles of alnustone in rats. The sample was precipitated with acetonitrile with 0.5% formic acid and separated on BEH C18 Column. The mobile phase was composed of 0.1% formic acid in water and methanol at a flow rate of 0.3 mL/min. Alnustone and the internal standard (caffeine) were quantitatively monitored with precursor-to-product ion transitions of m/z 262.9→105.2 and m/z 195.2→138.0, respectively. The calibration curve for alnustone was linear from 1 to 2000 ng/mL. The intra- and inter-day assay precision (RSD) ranged from 1.1-9.0 % to 3.3-8.6%, respectively and the intra- and inter-day assay accuracy (RE) was between -8.2-9.7% and -10.3-9.9%, respectively. The validated method was successfully applied to the pharmacokinetic studies of alnustone in rats. After single-dose intravenous administration of alnustone (5 mg/kg), the mean peak plasma concentration (Cmax) value was 7066.36 ± 820.62 ng/mL, and the mean area under the concentration-time curve (AUC0-t) value was 6009.79 ± 567.30 ng/mL∙h. Our results demonstrated that the residence time of alnustone in vivo was not long and it eliminated quickly from the rat plasma. Meanwhile, the drug is mainly distributed in tissues with large blood flow, and the lung and liver might be the target organs for alnustone efficacy. The study will provide information for further application of alnustone.


Assuntos
Cromatografia Líquida/métodos , Diarileptanoides/administração & dosagem , Diarileptanoides/farmacocinética , Espectrometria de Massas em Tandem/métodos , Administração Intravenosa , Animais , Cafeína/química , Calibragem , Diarileptanoides/sangue , Diarileptanoides/química , Limite de Detecção , Masculino , Ratos Sprague-Dawley , Padrões de Referência , Reprodutibilidade dos Testes , Distribuição Tecidual
6.
J Chromatogr A ; 1605: 360361, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31327479

RESUMO

Biogenic amines (BAs), mainly produced by amino acid decarboxylation, are widespread in foods and human organisms. Appropriate intake of BAs is beneficial to the human body, while excessive consumption may cause discomfort. Meanwhile, BAs are a kind of chemical marker for evaluating meat freshness. For these reasons, simple, rapid and efficient methods have been developed for the determination of BAs in food and biological products. This review introduces the provenance, classification and physiological activity of eight essential BAs and summarizes the dominant pretreatment and analysis methods since 2010. Pretreatment technologies mainly include the "dilute and shoot" method, ultrasonic assisted extraction, solid-phase extraction, matrix solid-phase dispersion, dispersive liquid-liquid microextraction, etc. Determination methods include liquid chromatography coupled to ultraviolet or fluorescence detectors, liquid chromatography tandem mass spectrometry, capillary electrophoresis, biosensors and so on.


Assuntos
Métodos Analíticos de Preparação de Amostras , Aminas Biogênicas/análise , Análise de Alimentos/métodos , Aminoácidos/análise , Animais , Aminas Biogênicas/química , Técnicas Biossensoriais , Humanos , Carne/análise
7.
Analyst ; 144(18): 5324-5352, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31348475

RESUMO

Medicinal plants with complex matrices are endowed with a wide scope of biological activities. The separation, quantification, characterization and purification of bioactive components from herbal medicine extracts have always challenged analysts. Fortunately, the advancement of various emerging techniques has provided potent support for improving the method selectivity, sensitivity and run speeds in medicinal plant analyses. In recent years, the advent of new-generation supercritical fluid chromatography (SFC) instruments and a wide diversity of column chemistries, coupled with the intrinsic technical features of SFC, have made it an alternative and prominent analytical platform in the medicinal plant research area. This work aims to give a comprehensive overview of the fundamentals, technical advancement and investigating parameters of SFC in combination with three prevalent detectors. Moreover, the latest research progress of SFC applications in medicinal plant analyses is illuminated, with focus on herbal medicine-related SFC papers on the analytical and preparative scale that were published during the period of 2012 to December 2018. The most relevant applications were classified based on the constituents to be analysed. As for the respective research cases, analytical protocols and data processing strategies were provided, along with the indicated restrictions or superiority of the method; thus, the current status of SFC in medicinal plant analysis was presented.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Compostos Fitoquímicos/análise , Plantas Medicinais/química , Cromatografia com Fluido Supercrítico/instrumentação
8.
Crit Rev Anal Chem ; : 1-25, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30900462

RESUMO

Recently, supercritical fluid chromatography (SFC) has attracted considerable attention for their application in food analysis. The use of supercritical CO2 (SC-CO2), as a mobile phase for SFC, with its low viscosity and high molecular diffusiveness, results in shorter analysis time and lower consumption of organic solvents as compared to high-performance liquid chromatography (HPLC). In addition, with recent improvements in its detection system, SFC has shown satisfactory selectivity and sensitivity. Thus, although the composition of food is complex, SFC remains a powerful tool in food analysis with some simple sample pretreatment techniques, such as liquid-liquid extraction, solid-phase extraction, and QuEChERS. Here, we summarize the applications of SFC in food quality and safety from 2012 to 2018, and mainly focus on sample pretreatment strategies and analysis conditions.

9.
Toxicol Lett ; 299: 56-66, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30232032

RESUMO

Cadmium exposure is closely associated with a variety of diseases including cancers and the accumulation of cadmium has been long recognized as a public health problem. It is therefore of high importance to find methods to reduce cadmium accumulation in the human body. Herein, we report that administration of betulinic acid (BA) protects mice from cadmium chloride (CdCl2)-induced toxicity by inhibiting cadmium-induced apoptosis in both kidney and liver. Mice were given oral doses of 3 mg/kg, 10 mg/kg and 30 mg/kg of BA daily for ten consecutive days, and were injected with one dose of 1 mg/kg CdCl2 after one hour of BA administration every day. The levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and blood urea nitrogen (BUN) were assessed by ELISA. Residual cadmium was determined by atomic absorption analysis. Protein expression was evaluated by western blotting. Pretreatment with BA significantly reduced residual cadmium levels in the liver, kidney and testis, increased the cadmium output in urine, and reduced tissue damage induced by CdCl2. Moreover, BA prevented body weight loss by CdCl2 in a dose dependent manner. Furthermore, BA treatment increased the expression levels of B-cell lymphoma 2 (Bcl-2), decreased Bcl-2-associated X (Bax), and inhibited the levels of active caspase-3. Importantly, BA within a dose of 30 mg/kg did not induce any signs of toxicity, and protected mice from the toxicity induced by CdCl2 in a dose-dependent manner. Our findings suggest that BA inhibits CdCl2 induced apoptosis in the kidney and liver, and BA may be an effective agent for the prevention and treatment of cadmium-induced diseases in humans.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Cloreto de Cádmio/toxicidade , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Triterpenos/farmacologia , Animais , Relação Dose-Resposta a Droga , Rim/metabolismo , Rim/patologia , Fígado/metabolismo , Fígado/patologia , Camundongos Endogâmicos , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
10.
Molecules ; 23(6)2018 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-29921801

RESUMO

Vitamins are a class of essential nutrients in the body; thus, they play important roles in human health. The chemicals are involved in many physiological functions and both their lack and excess can put health at risk. Therefore, the establishment of methods for monitoring vitamin concentrations in different matrices is necessary. In this review, an updated overview of the main pretreatments and determination methods that have been used since 2010 is given. Ultrasonic assisted extraction, liquid⁻liquid extraction, solid phase extraction and dispersive liquid⁻liquid microextraction are the most common pretreatment methods, while the determination methods involve chromatography methods, electrophoretic methods, microbiological assays, immunoassays, biosensors and several other methods. Different pretreatments and determination methods are discussed.


Assuntos
Extração Líquido-Líquido/métodos , Ondas Ultrassônicas , Vitaminas/análise , Vitaminas/isolamento & purificação , Humanos
12.
Nat Prod Res ; 31(17): 1995-2000, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28049349

RESUMO

The present study was designed to investigate the chemical constituents and bioactivities of the roots of Eleutherococcus sessiliflorus (E. sessiliflorus). The compounds were isolated through various chromatography techniques and elucidated by mass spectrometric (MS), 1D- and 2D-NMR analyses. The sedative-hypnotic effect of E. sessiliflorus ethanol extract and its fractions (acetic ether, n-butanol and water fraction) were also investigated. In the chemical constituent study, one new compound, 3-ethyl-5-hydroxy-3-(hydroxymethyl) pentyl-3-(3,4-dihydroxyphenyl) acrylate and fourteen known compounds were isolated and identified. The chromatographic fingerprint of E. sessiliflorus was established by UPLC-PDA-MS/MS analysis. In bioactivity study, it was found that the water fraction of E. sessiliflorus extract could prolong pentobarbital-induced sleeping time more than that of the other fractions of E. sessiliflorus extract in mice, which provided a basis for future study on sedative-hypnotic effect of the chemical constituents in E. sessiliflorus.


Assuntos
Eleutherococcus/química , Hipnóticos e Sedativos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , 1-Butanol/química , Animais , Etanol , Hipnóticos e Sedativos/química , Masculino , Camundongos , Pentobarbital/farmacologia , Extratos Vegetais/análise , Raízes de Plantas/química , Sono/efeitos dos fármacos , Espectrometria de Massas em Tandem
13.
BMC Oral Health ; 16(1): 101, 2016 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-27659310

RESUMO

BACKGROUND: Streptococcus mutans forms biofilms as a resistance mechanism against antimicrobial agents in the human oral cavity. We recently showed that human cathelicidin LL-37 exhibits inhibitory effects on biofilm formation of S. mutans through interaction with lipoteichoic acid (LTA), but without antibacterial or biofilm dispersal abilities. (-)-Epigallocatechin gallate (EGCG) is the most abundant constituent of tea catechins that has the greatest anti-infective potential to inhibit the growth of various microorganisms and biofilm formation. Therefore, in this study, we evaluated whether LL-37 interacts with EGCG to enhance the antibiofilm effect of EGCG on S. mutans biofilm formation. METHODS: Clinical S. mutans strains (n = 10) isolated from children's saliva were tested in a biofilm formation assay. The antibiofilm effect of EGCG with and without LL-37 was analyzed by the minimum biofilm eradication concentration assay and confirmed using field emission-scanning electron microscopy. In addition, the interaction among EGCG, LL-37, and LTA of S. mutans was determined using quartz crystal microbalance analysis. RESULTS: EGCG killed 100 % of planktonic S. mutans within 5 h, inhibited biofilm formation within 24 h, and reduced bacteria cells in preformed biofilms within 3 h at a concentration of 0.2 mg/mL. However, EGCG did not appear to interact with LTA. LL-37 effectively enhanced the bactericidal activity of EGCG against biofilm formation and preformed biofilms as determined by quantitative crystal violet staining and field emission-scanning electron microscopy. In addition, quartz crystal microbalance analysis revealed that LL-37 interacted with EGCG and promoted binding between EGCG and LTA of S. mutans. CONCLUSIONS: We show that LL-37 enhances the antibiofilm effect of EGCG on S. mutans. This finding provides new knowledge for dental treatment by using LL-37 as a potential antibiofilm compound.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Biofilmes/efeitos dos fármacos , Streptococcus mutans , Catequina/análogos & derivados , Catequina/farmacologia , Humanos , Testes de Sensibilidade Microbiana
14.
J Asian Nat Prod Res ; 18(9): 823-30, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27089930

RESUMO

Four new diterpenoids named 1-epi-9-hydroxydepressin (1), 1-epi-8-hydroxydepressin (2), 2,13,9-trihydroxy-labda-8(17),12(E),14-triene (3) and tagalsin I (4) were isolated from Euphorbia rapulum. The structures of these compounds were elucidated by means of various spectroscopic methods. All the isolated compounds were evaluated for cytotoxic activities against HepG2, MCF-7, and C6 cell lines, and compound 4 showed moderate selective activity against MCF-7 cell line with an IC50 value of 31.8 µM.


Assuntos
Diterpenos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Euphorbia/química , Animais , Diterpenos/química , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Humanos , Concentração Inibidora 50 , Células MCF-7 , Estrutura Molecular , Raízes de Plantas/química , Ratos
15.
J Chromatogr A ; 1432: 132-9, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26780846

RESUMO

An analytical method based on ultra-high performance supercritical fluid chromatography (UHPSFC) with photo-diode array detection (PDA) has been developed to quantify 15 sulfonamides and their N4-acetylation metabolites in serum. Under the optimized gradient elution conditions, it took only 7min to separate all 15 sulfonamides and the critical pairs of each parent drug and metabolite were completely separated. Variables affecting the UHPSFC were optimized to get a better separation. The performance of the developed method was evaluated. The UHPSFC method allowed the baseline separation and determination of 15 sulfonamides and metabolites with limit of detection ranging from 0.15 to 0.35µg/mL. Recoveries between 90.1 and 102.2% were obtained with satisfactory precision since relative standard deviations were always below 3%. The proposed method is simple, accurate, time-saving and green, it is applicable to a variety of sulfonamides detection in serum samples.


Assuntos
Sulfonamidas/sangue , Cromatografia com Fluido Supercrítico/métodos , Humanos , Sulfanilamidas/sangue
16.
Molecules ; 14(3): 953-8, 2009 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-19255553

RESUMO

Two new neolignans, (7S,8R)-guaiacylglycerol-8-O-4'-sinapyl ether 9'-O-beta-D- glucopyranoside (1) and (7S,8R)-syringylglycerol-8-O-4'-sinapyl ether 9'-O-beta-D-gluco- pyranoside (2) were isolated from the leaves of Syringa velutina Kom.. Their structures were established by chemical properties and spectroscopic evidence.


Assuntos
Lignanas/química , Syringa/química , Lignanas/isolamento & purificação , Estrutura Molecular , Folhas de Planta/química
17.
Zhong Yao Cai ; 31(5): 679-81, 2008 May.
Artigo em Chinês | MEDLINE | ID: mdl-18826143

RESUMO

OBJECTIVE: To study the chemical constituents of Syringa veutina Kom. METHODS: The constituents were isolated and repeatedly purified on silica and Sephadex LH-20 column chromatography. They were dentified and structurally elucidated by spectral analysis. RESULTS: Seven compounds were obtained. They were identified as Syningin(1), Liriodendrin(2), (+) -Medioresinol di-O-beta-D-glucopyranosied (3), Rutin(4), Quercetin 3-O-beta-D-glucopyranoside (5), Kaempferol-3-O-beta-D-glucopyranosied (6), D-mannitol (7). CONCLUSION: Compound 2 and 3 were isolated from this genus for the first time. Compound 4, 5, 6 and 7 were isolated from this plant for the first time.


Assuntos
Furanos/isolamento & purificação , Glucosídeos/isolamento & purificação , Plantas Medicinais/química , Quercetina/análogos & derivados , Syringa/química , Furanos/química , Glucosídeos/química , Espectroscopia de Ressonância Magnética , Fenilpropionatos/química , Fenilpropionatos/isolamento & purificação , Folhas de Planta/química , Quercetina/química , Quercetina/isolamento & purificação , Rutina/química , Rutina/isolamento & purificação
18.
Zhong Yao Cai ; 30(4): 418-20, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17674793

RESUMO

OBJECTIVE: To establish an HPLC method for the simultaneous determination of four bioactive cucurbitacins in Cucubita pepo cv Dayangua. METHODS: The HPLC chromatography was carried out with a lineal gradient programming and detection wavelength at 215 nm. Kromasil C8 column (150 mm x 4.6 mm ID, 5 microm)was used. The mobile phase was acetonitrile-water (containing 2.0% HAc) and the flow rate was 1.0 ml/min. RESULTS: The linear range of 23, 24-dihydrocucurbitacin F was 0.28-5.6 microg/ml (r = 0.9978), 23, 24-dihydrocucurbitacin D 0.39-7.8 microg/ml (r = 0.9986), cucurbitacin B 0.304-6.08 microg/ml (r = 0.9983), cucurbitacin E 2. 52 -50. 4 microg/ml (r = 0.9998). The method was accurate with variation less than 5% and recovery more than 95%. CONCLUSION: The method is successfully applied to determination of the four cucurbitacins from Cucubita pepo cv dayangua.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cucurbita/química , Cucurbitacinas/análise , Plantas Medicinais/química , Cucurbitacinas/isolamento & purificação , Reprodutibilidade dos Testes , Triterpenos/análise , Triterpenos/isolamento & purificação
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