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1.
J Food Drug Anal ; 26(1): 90-99, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29389593

RESUMEN

Polygoni Multiflori Radix (PMR) is increasingly being used not just as a traditional herbal medicine but also as a popular functional food. In this study, multivariate chemometric methods and mass spectrometry were combined to analyze the ultra-high-performance liquid chromatograph (UPLC) fingerprints of PMR from six different geographical origins. A chemometric strategy based on multivariate curve resolution-alternating least squares (MCR-ALS) and three classification methods is proposed to analyze the UPLC fingerprints obtained. Common chromatographic problems, including the background contribution, baseline contribution, and peak overlap, were handled by the established MCR-ALS model. A total of 22 components were resolved. Moreover, relative species concentrations were obtained from the MCR-ALS model, which was used for multivariate classification analysis. Principal component analysis (PCA) and Ward's method have been applied to classify 72 PMR samples from six different geographical regions. The PCA score plot showed that the PMR samples fell into four clusters, which related to the geographical location and climate of the source areas. The results were then corroborated by Ward's method. In addition, according to the variance-weighted distance between cluster centers obtained from Ward's method, five components were identified as the most significant variables (chemical markers) for cluster discrimination. A counter-propagation artificial neural network has been applied to confirm and predict the effects of chemical markers on different samples. Finally, the five chemical markers were identified by UPLC-quadrupole time-of-flight mass spectrometer. Components 3, 12, 16, 18, and 19 were identified as 2,3,5,4'-tetrahydroxy-stilbene-2-O-ß-d-glucoside, emodin-8-O-ß-d-glucopyranoside, emodin-8-O-(6'-O-acetyl)-ß-d-glucopyranoside, emodin, and physcion, respectively. In conclusion, the proposed method can be applied for the comprehensive analysis of natural samples.


Asunto(s)
Cromatografía Líquida de Alta Presión , Gastrópodos/química , Gastrópodos/clasificación , Metabolómica , Animales , Espectrometría de Masas , Metabolómica/métodos , Estructura Molecular
2.
Carbohydr Polym ; 132: 437-43, 2015 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-26256368

RESUMEN

Xue-Zhi-Ning (XZN) is a traditional Chinese medicine formula, containing active ingredients with poor solubility in water, which has been demonstrated to be helpful for patients with hyperlipidemia. One-pot ß-cyclodextrin (ß-CD)-assisted extraction of active ingredients from XZN has been carried out to develop an efficient and eco-friendly extraction process. Five active compounds--rubrofusarin gentiobioside, 2,3,5,4'-tetrahydroxy-stilbene-2-O-ß-D-glucoside, emodin, nuciferine and quercetin--were identified by UPLC/DAD/MS and used as indexes to evaluate the process optimized by an orthogonal test. The results showed that addition of ß-CD significantly enhanced the extraction ratios of all five components. The enhancement of extraction ratios was positively correlated with the apparent formation constants between ß-CD and the compounds. The study also showed that the stabilities and dissolution rates of the active ingredients were improved in the presence of ß-CD. This one-pot ß-cyclodextrin-assisted extraction has the potential to be applied in pharmaceutical preparations directly.


Asunto(s)
Medicamentos Herbarios Chinos/análisis , beta-Ciclodextrinas/química , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/aislamiento & purificación , Concentración de Iones de Hidrógeno , Espectrometría de Masas , Medicina Tradicional China , Solubilidad , Agua
3.
Chem Commun (Camb) ; 51(20): 4237-40, 2015 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-25670321

RESUMEN

A facile strategy to prepare snap-top magnetic nanocarriers has been developed where ultrasmall superparamagnetic Fe3O4 nanoparticles were used as the core with mesoporous silica as the shell followed by the covalent installation of a layer of ß-cyclodextrins on the outer surfaces. The smart hybrid nanomaterials showed remarkable pH- and sugar-responsive cargo release property and low cytotoxicity as proved by an MTT assay with HEK293T cell lines.


Asunto(s)
Ácido Deshidroascórbico/química , Portadores de Fármacos/química , Óxido Ferrosoférrico/química , Nanopartículas/química , Dióxido de Silicio/química , beta-Ciclodextrinas/química , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/farmacología , Liberación de Fármacos , Óxido Ferrosoférrico/farmacología , Células HEK293 , Humanos , Concentración de Iones de Hidrógeno , Porosidad , Dióxido de Silicio/farmacología , beta-Ciclodextrinas/farmacología
4.
J Asian Nat Prod Res ; 17(2): 170-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25434469

RESUMEN

A novel unusual trimmer chalcone, polyanthumin (1), together with five known compounds myricetin 3-O-(3″-O-galloyl)-α-l-rhamnopyranoside (2), sulfuretin (3), fustin (4), gallic acid (5), and ethyl gallate (6), was isolated from the dry stems of Memecylon polyanthum H.L. Li. Among them, compound 1 is a new chalcone trimmer with a novel cyclobutane skeleton in nature. Compounds 3 and 4 are flavonoids carrying a single 7-OH in A ring, which provided the first example of these class flavonoids from the family Melastomataceae. In addition, the antitumor activities for 2-4 were reported for the first time in this study. The antitumor effects of the isolated compounds 1-6 in vitro were assayed by the SRB method using human cancer K562 cells, with the inhibition rates ranging from 39.4% to 54.5% at 100 µg/ml. The IC50 values of compounds 1 and 3 for the inhibition of K562 cell proliferation were determined to be 45.4 and 30.5 µg/ml, respectively. To the best of our knowledge, compound 1 was the second sample as chalcone trimer. In addition, the antitumor activities for 2-4 were reported for the first time in this study.


Asunto(s)
Antineoplásicos/aislamiento & purificación , Chalcona/aislamiento & purificación , Ciclobutanos/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Melastomataceae/química , Antineoplásicos/química , Antineoplásicos/farmacología , Benzofuranos/aislamiento & purificación , Chalcona/química , Chalcona/farmacología , Chalconas , Ciclobutanos/química , Ciclobutanos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Espectroscopía de Resonancia por Spin del Electrón , Flavonoides/aislamiento & purificación , Ácido Gálico/análogos & derivados , Ácido Gálico/aislamiento & purificación , Humanos , Células K562 , Estructura Molecular , Tallos de la Planta/química , Estereoisomerismo
5.
Chemistry ; 20(11): 2998-3004, 2014 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-24585543

RESUMEN

Acetylcholine (ACh), a neurotransmitter located in cholinergic synapses, can trigger cargo release from mesoporous silica nanoparticles equipped with calixarene- or pillarene-based nanovalves by removing macrocycles from the stalk components. The amount and speed of cargo release can be controlled by varying the concentration of ACh in solution or changing the type of gating macrocycle. Although this proof-of-concept study is far from a real-life application, it provides a possible route to treat diseases related to the central nervous system.


Asunto(s)
Acetilcolina/química , Acetilcolina/farmacología , Materiales Biocompatibles/química , Calixarenos/química , Sistema Nervioso Central/química , Sistema Nervioso Central/efectos de los fármacos , Compuestos Macrocíclicos/química , Nanopartículas/química
6.
J Ethnopharmacol ; 151(1): 609-17, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24315982

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The dried fruit of Psoralea corylifolia L. has been used to prevent and treat vitiligo, osteoporosis, arthralgia and asthma in Traditional Chinese Medicine for some 1600 years. Psoralen (P), isopsoralen (IP), psoralenoside (PO) and isopsoralenoside (IPO) are the major coumarins and coumarin-related benzofuran glycosides in Psoraleae Fructus, which have been reported to show estrogen-like activity, osteoblastic proliferation accelerating activity, antitumor effects and antibacterial activity. The first aim of this study is to develop a rapid, sensitive and selective ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) approach for simultaneous determination of PO, IPO, P and IP in rat plasma and samples collected from in vitro incubation experiments. The second aim is to investigate the pharmacokinetic properties of PO, IPO, P and IP after oral administration of Psoralea corylifolia extract (PCE) to rats. The third aim is to confirm the biotransformation of PO to P or IPO to IP under gastrointestinal conditions. MATERIALS AND METHODS: A UPLC-MS/MS method with a C18 column and a mobile phase of methanol-0.1% aqueous formic acid was validated according to the criteria in FDA guidelines about bioanalytical method, which was developed to investigate the pharmacokinetic behavior of PO, IPO, P and IP from PCE and the metabolic pathways of PO to P or IPO to IP. RESULTS: The criteria for establishment of a new UPLC-MS/MS method including selectivity, linearity, accuracy, precision, extraction recovery, matrix effect and stability were validated. This method was successfully applied to the quantitative determination of PO, IPO, P and IP in biological samples collected from both in vitro incubations and in vivo rat experiments. After oral administration of PCE to rat, pharmacokinetic parameters of these four compounds indicated that in vivo biotransformation may occur between PO and P or IPO and IP. Purified benzofuran glycosides fraction (PBGF), containing only PO and IPO, was orally administered to rats to further confirm the biotransformation of PO to P or IPO to IP under gastrointestinal conditions. An in vitro incubation study elucidated that PO and IPO were metabolized to P and IP by intestinal microflora through de-glucosylation. CONCLUSIONS: This paper developed a rapid, sensitive and selective UPLC-MS/MS method for simultaneous determination of PO, IPO, P and IP from PCE in biological samples, and investigated on their comprehensive in vivo and in vitro pharmacokinetic studies. These obtained results showed that the metabolism by intestinal bacteria plays an important role in pharmacological effects of orally administered PCE.


Asunto(s)
Benzofuranos/química , Benzofuranos/farmacocinética , Glicósidos/química , Glicósidos/farmacocinética , Extractos Vegetales/química , Psoralea/química , Animales , Benzofuranos/sangre , Cromatografía Liquida , Ficusina/sangre , Ficusina/química , Ficusina/farmacocinética , Frutas/química , Furocumarinas/sangre , Furocumarinas/química , Furocumarinas/farmacocinética , Glicósidos/sangre , Masculino , Estructura Molecular , Ratas , Ratas Sprague-Dawley , Espectrometría de Masas en Tándem
7.
ACS Macro Lett ; 2(6): 522-526, 2013 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-35581810

RESUMEN

Considering the high reactivity of the C-H bonds in fluorobenzenes for direct arylation and special properties of fluorinated polymers, herein, synthesis of fluorinated porous organic polymers via direct C-H arylation polycondensation is explored. The obtained polymers (FPOP-1 and FPOP-2) are well characterized and show high porosities with Brunauer-Emmett-Teller specific surface area of above 1000 m2 g-1. Different pore size distribution (PSD) profiles of porous polymers can be obtained by selecting different core constructing monomers. FPOP-2 exhibits a relatively narrower PSD with the dominant pore size at about 0.63 nm, which is more suitable for adsorption of small gas molecules (H2, CO2, and CH4) than FPOP-1. As a porous fluorinated hydrophobic material, FPOP-2 possesses high adsorption ability for toluene (976 mg g-1 at saturated vapor pressure and room temperature) due to its high porosities and binding affinities between the guest molecules and the host network. The good sorption capacity of FPOP-2 for toluene makes it show potential applications in elimination of harmful small aromatic molecules in the environment.

8.
Yao Xue Xue Bao ; 46(7): 822-7, 2011 Jul.
Artículo en Chino | MEDLINE | ID: mdl-22010352

RESUMEN

A rapid and sensitive analytical method was developed for the simultaneous determination of fumonisins B1 and B2 in traditional Chinese medicines by HPLC-MS/MS. The detection limits for fumonisins B1 and B2 were 0.25 ng x mL(-1) corresponding to 2 microg x kg(-1) in samples. Recoveries from different samples spiked with fumonisins B1 and B2 at levels ranging from 0.2 to 3 mg x kg(-1) were 84.0%-96.1% and 86.3%-99.3%, respectively. Among the total of 34 samples purchased from local markets, ten samples of which were visibly moldy samples due to inappropriate storage, and 24 were normal samples. The results showed that 6 of the visibly moldy samples and 5 of the normal samples were contaminated with total fumonisins at levels ranging 82.4-2349 microg x kg(-1) and 102-729 microg x kg(-1), respectively.


Asunto(s)
Medicamentos Herbarios Chinos/química , Fumonisinas/análisis , Plantas Medicinales/química , Cromatografía Líquida de Alta Presión , Contaminación de Medicamentos , Medicina Tradicional China , Espectrometría de Masas en Tándem
9.
J Agric Food Chem ; 59(8): 4294-9, 2011 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-21410236

RESUMEN

The p-sulfonatocalix[n]arenes are supposed to show potential application in the clinical treatment of viologen poisoning. In the present study, p-sulfonatocalix[4]arene (C4AS), the most common derivative of p-sulfonatocalix[n]arenes, is used to study the antidotic mechanism for paraquat (PQ) by pharmacokinetics in vivo. A high-performance liquid chromatography (HPLC) method was established to determine the concentration of PQ in rat plasma. The results showed that the peak plasma concentration (C(max)) and area under the plasma concentration-time curve (AUC(0-t)) were significantly lower after C4AS intervention than in the PQ intoxication group. It was considered that C4AS has great effective detoxication to PQ poisoning, and the results of in vitro intestinal absorption studies showed that C4AS can inhibit the absorption of PQ via oral administration by forming a stable inclusion constant.


Asunto(s)
Herbicidas/farmacocinética , Inactivación Metabólica , Paraquat/farmacocinética , Animales , Área Bajo la Curva , Calixarenos , Cromatografía Líquida de Alta Presión , Herbicidas/toxicidad , Absorción Intestinal , Masculino , Paraquat/toxicidad , Fenoles , Ratas , Reproducibilidad de los Resultados
10.
Org Biomol Chem ; 9(7): 2219-26, 2011 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-21298179

RESUMEN

Neutral sugar-bearing tetraphenylethenes (TPE) are designed and prepared as "turn-on" luminescent sensors for lectins and glycosidases based on aggregation-induced emission. Through aggregation derived from carbohydrate-lectin binding, multivalent mannosyl-bearing TPE shows a good selectivity and sensitivity to Con A by switching on the fluorescence of water-soluble tetraphenylethylene-based glyco-conjugates in aqueous solution. Meanwhile, cellobiosyl-bearing TPE can be used to investigate enzymatic hydrolysis based on emission enhancing by glycosidase-induced aggregation.


Asunto(s)
Carbohidratos/química , Etilenos/análisis , Colorantes Fluorescentes/análisis , Lectinas/química , Metabolismo de los Hidratos de Carbono , Etilenos/química , Hidrólisis , Lectinas/metabolismo , Estructura Molecular
11.
J Pharm Biomed Anal ; 55(1): 211-5, 2011 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-21282026

RESUMEN

The hydrolytic kinetics and degradation mechanism of 2,3,5,4'-tetrahydroxystilbene-2-O-ß-d-glycoside (THSG) extracted from Radix Polygoni Multiflori (a commonly used official Chinese herbal Heshouwu), were investigated using reversed-phase high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS). The influences of pH (1.5-9.9), temperature (25-60°C) and irradiation on the hydrolysis of THSG were studied in aqueous solutions. The results showed that the degradation of THSG was pH-, temperature- and irradiation-dependent and all followed first-order kinetics. The effect of temperature on the rate of THSG degradation was characterized using the Arrhenius equation. Maximum stability of THSG was found at pH 1.5 (t(0.5)=47.57 d). THSG was unstable in alkaline and irradiation conditions. The active energy (E(a)) of THSG degradation in aqueous solution at pH 6.8 (most frequently adopted extract solvent) under lucifugal and irradiation conditions was 47.7kJmol(-1) and 25.3kJmol(-1), respectively. Three hydrolytic products of THSG were identified by LC-MS. Cis-trans isomerism took place under irradiation, and hydrolysis took place in acid-base conditions. Moreover, further oxidation on aglycon occurred after hydrolytic cleavage of phenolic glycoside in acidic conditions. The possible hydrolytic pathways of THSG are proposed.


Asunto(s)
Glucósidos/química , Hipolipemiantes/química , Estilbenos/química , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos , Glucósidos/efectos de la radiación , Calor/efectos adversos , Concentración de Iones de Hidrógeno , Hidrólisis/efectos de la radiación , Hipolipemiantes/efectos de la radiación , Isomerismo , Cinética , Luz/efectos adversos , Oxidación-Reducción , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Ultravioleta , Estilbenos/efectos de la radiación
12.
Chem Commun (Camb) ; 46(23): 4067-9, 2010 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-20454747

RESUMEN

Grafting of glucosamine hydrochloride moieties to tetraphenylethylene (TPE) motif furnished a novel cationic water-soluble tetraphenylethylene derivative (GH-TPE). With aggregation-induced emission properties, GH-TPE was used for fluorometric detection to alkaline phosphatase through enzyme-triggered de-aggregation of the ensemble of GH-TPE and substrate.


Asunto(s)
Fosfatasa Alcalina/análisis , Colorantes Fluorescentes/química , Fluorometría/métodos , Glucosamina/análogos & derivados , Glucosamina/química , Estilbenos/química , Triazoles/química
13.
J Biomed Mater Res A ; 66(4): 770-8, 2003 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-12926028

RESUMEN

Our objective in this study was to investigate the efficiency of two treatments for poly (L-lactic acid) (PLLA) surface modification with gelatin, via entrapment and coupling, using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS). The properties of original PLLA, gelatin-entrapped, and coupled PLLA films were investigated by water contact angle measurement and electron spectroscopy for chemical analysis (ESCA). The water contact angle indicated that the incorporation of gelatin resulted in a change in hydrophilicity, and the ESCA data suggested that the modified PLLA films became enriched with nitrogen atoms. The cytocompatibility of modified PLLA films might be improved. Therefore, we examined the attachment and proliferation of bovine articular chondrocyte seeded on modified PLLA films and virgin films. A whole-cell enzyme-linked immunosorbent assay (cell ELISA) that detects 5-bromo-2'-deoxyuridine (BrdU) incorporation during DNA synthesis and collagen type II secretion was applied to evaluate the chondrocytes on different PLLA films and tissue culture plates (TCPS). Cell viability was estimated by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay, and cell function was assessed by measuring glycosaminoglycan (GAG) secreted by chondrocytes. These results implied that gelatin used to modify the PLLA surface through entrapment and coupling could enhance chondrocyte adhesion, proliferation, and function.


Asunto(s)
Cartílago Articular/citología , Ácido Láctico , Imitación Molecular , Polímeros , Animales , Carbodiimidas , Cartílago Articular/química , Bovinos , Adhesión Celular , División Celular , Colágeno/análisis , Ensayo de Inmunoadsorción Enzimática , Glicosaminoglicanos/biosíntesis , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Modelos Biológicos , Poliésteres , Succinimidas
14.
Biomaterials ; 24(21): 3859-68, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12818559

RESUMEN

The objective of this study was to investigate the efficiency of two treatments for poly(L-lactic acid) (PLLA) surface modification with chitosan, via entrapment and coupling by using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide. The properties of original PLLA films, chitosan-entrapped and coupled PLLA films were investigated by water contact angle measurement and electron spectroscopy for chemical analysis (ESCA). The contact angle indicated the change in hydrophilicity and the ESCA data suggested that the modified PLLA films became enriched with nitrogen atoms. The cytocompatibility of modified PLLA films might be improved. Therefore, the attachment and proliferation of bovine articular chondrocyte seeded on modified PLLA films and control one were examined. A whole cell enzyme-linked immunosorbent assay (Cell ELISA) that detects the BrdU incorporation during DNA synthesis and collagen type II secretion was applied to evaluate the chondrocytes on different PLLA films and tissue culture plates. Cell viability was estimated by the MTT assay and cell function were assessed by measuring sulfated glycosaminoglycan secreted by chondrocytes. These results implied that chitosan used to modify PLLA surface through entrapment and coupling could enhance the chondrocyte adhesion, proliferation and function.


Asunto(s)
Materiales Biocompatibles/química , Cartílago Articular/citología , Quitina/análogos & derivados , Quitina/química , Condrocitos/citología , Ácido Láctico/química , Polímeros/química , Animales , Bromodesoxiuridina/farmacología , Cartílago Articular/efectos de los fármacos , Bovinos , Adhesión Celular , División Celular , Supervivencia Celular , Quitosano , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Colágeno/química , Colorantes/farmacología , ADN/química , Ensayo de Inmunoadsorción Enzimática , Glicosaminoglicanos/metabolismo , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Nitrógeno/química , Poliésteres , Propiedades de Superficie , Sales de Tetrazolio/química , Sales de Tetrazolio/farmacología , Tiazoles/química , Tiazoles/farmacología , Factores de Tiempo , Agua/química
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