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1.
Eur J Epidemiol ; 39(4): 433-445, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38589644

RESUMEN

The DEEP cohort is the first population-based cohort of pregnant population in China that longitudinally documented drug uses throughout the pregnancy life course and adverse pregnancy outcomes. The main goal of the study aims to monitor and evaluate the safety of drug use through the pregnancy life course in the Chinese setting. The DEEP cohort is developed primarily based on the population-based data platforms in Xiamen, a municipal city of 5 million population in southeast China. Based on these data platforms, we developed a pregnancy database that documented health care services and outcomes in the maternal and other departments. For identifying drug uses, we developed a drug prescription database using electronic healthcare records documented in the platforms across the primary, secondary and tertiary hospitals. By linking these two databases, we developed the DEEP cohort. All the pregnant women and their offspring in Xiamen are provided with health care and followed up according to standard protocols, and the primary adverse outcomes - congenital malformations - are collected using a standardized Case Report Form. From January 2013 to December 2021, the DEEP cohort included 564,740 pregnancies among 470,137 mothers, and documented 526,276 live births, 14,090 miscarriages and 6,058 fetal deaths/stillbirths and 25,723 continuing pregnancies. In total, 13,284,982 prescriptions were documented, in which 2,096 chemicals drugs, 163 biological products, 847 Chinese patent medicines and 655 herbal medicines were prescribed. The overall incidence rate of congenital malformations was 2.0% (10,444/526,276), while there were 25,526 (4.9%) preterm births and 25,605 (4.9%) live births with low birth weight.


Asunto(s)
Resultado del Embarazo , Humanos , Embarazo , Femenino , China/epidemiología , Resultado del Embarazo/epidemiología , Adulto , Estudios de Cohortes , Complicaciones del Embarazo/tratamiento farmacológico , Complicaciones del Embarazo/epidemiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Recién Nacido , Bases de Datos Factuales , Nacimiento Prematuro/epidemiología
2.
J Asian Nat Prod Res ; 15(5): 502-6, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23600859

RESUMEN

The phytochemical investigation of the flower buds of Daphne genkwa yielded four highly oxygenated tigliane diterpene esters (1-4), including two new phorbol derivatives, 12-O-(2'E,4'E-decadienoyl)-7-oxo-5-ene-phorbol-13-acetate (1) and 12-O-neodecanoyl-7-oxo-5-ene-phorbol-13-acetate (2). The molecular structures of the isolated compounds were elucidated on the basis of extensive spectroscopic analysis, including 1D and 2D NMR.


Asunto(s)
Daphne/química , Diterpenos/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Forboles/aislamiento & purificación , Diterpenos/química , Medicamentos Herbarios Chinos/química , Ésteres , Flores/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Forboles/química
3.
Zhong Yao Cai ; 36(5): 752-5, 2013 May.
Artículo en Zh | MEDLINE | ID: mdl-24218967

RESUMEN

OBJECTIVE: To study the chemical constituents from flowers of Gardenia jasminoides. METHODS: The compounds were isolated and purified by column chromatography and their structures were elucidated through spectroscopic techniques (NMR) and physicochemical properties. RESULTS: 15 compounds were isolated from flowers of G. jasminoides, and identified as 5, 7, 3'-trihydroxy-6, 4', 5'-trimethoxyflavone (1), 5, 7, 3', 5'- tetrahydroxy-6, 4'-dymethoxyflavone (2), kaempferol (3), quercetin (4), 3beta,23- dihydroxyurs-12-en-28-oic acid (5), 3beta,19alpha-dihydroxy-urs-12-en-28-oic acid (6), 3beta,19alpha,23-trihydroxy-urs-12-en-28-oic acid (7), emodin (8), physcion (9), crocin-I (10), beta-daucosterol (11), beta-sitosterol (12), stearic acid (13), palmitic acid (14), oleic acid (15). CONCLUSION: Compounds 1 - 15 are isolated from flowers of G. jasminoides and compounds 5 and 6 are isolated from genus Gardenia for the first time.


Asunto(s)
Flores/química , Gardenia/química , Glicósidos/química , Extractos Vegetales/química , Triterpenos/química , Flavonoides/química , Flavonoides/aislamiento & purificación , Glicósidos/aislamiento & purificación , Quempferoles/química , Quempferoles/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura Molecular , Extractos Vegetales/aislamiento & purificación , Triterpenos/aislamiento & purificación
4.
Zhongguo Zhong Yao Za Zhi ; 36(16): 2233-5, 2011 Aug.
Artículo en Zh | MEDLINE | ID: mdl-22097337

RESUMEN

OBJECTIVE: To develop a RP-HPLC method for determining the contents of atranol, lecanorin, ethyl orsellinate and methyl orsellinate in Usnea diffracta. METHOD: A Kromasil-C18 column (4.6 mm x 250 mm, 5 microm) was used at 25 degrees C with the mobile phases of acetonitrile -1% acetic acid in a gradient manner. The flow rate was set at 1.0 mL x min(-1). The detection wavelength was 280 nm. RESULT: The correlation coefficients of atranol, lecanorin, ethyl orsellinate, and methyl orsellinate were higher than 0.999. Recoveries were from 102.9% to 95.30%; with RSD from 2.3% to 1.9%. CONCLUSION: The method is quick, simple and repeatable for simultaneous determination of atranol, lecanorin, ethyl orsellinate and methyl orsellinate in U. diffracta.


Asunto(s)
Benzaldehídos/análisis , Cromatografía Líquida de Alta Presión/métodos , Resorcinoles/análisis , Usnea/química
5.
Zhong Yao Cai ; 34(4): 546-8, 2011 Apr.
Artículo en Zh | MEDLINE | ID: mdl-21809539

RESUMEN

OBJECTIVE: To study the chemical constituents of Codonopsis pilosula. METHODS: The compounds were isolated and purified by column chromatography and their structures were elucidated through spectroscopic techniques (NMR) and physicochemical properties. RESULTS: The compounds were isolated as hesperidin(I), n-hexyl beta-sophoroside(II), atractylenolide III (III), lobetyolin(IV), lobetyolinin(V), taraxerol(VI), taraxeryl acetate(VII), alpha-spinasterol(VIII),9,10,13-trihydroxy-(E)-11-octadecenoic acid (IX),beta-sitosterol(X),beta-daucosterol(XI)and sugar(XII). CONCLUSION: Compounds 1 -2 and 9 are isolated from this plant for the first time.


Asunto(s)
Codonopsis/química , Hesperidina/aislamiento & purificación , Hidroxiácidos/aislamiento & purificación , Ácidos Oléicos/aislamiento & purificación , Plantas Medicinales/química , Hesperidina/química , Hidroxiácidos/química , Lactonas/química , Lactonas/aislamiento & purificación , Estructura Molecular , Ácidos Oléicos/química , Poliinos/química , Poliinos/aislamiento & purificación , Control de Calidad , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación
6.
J Sep Sci ; 33(12): 1730-8, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20405483

RESUMEN

An ultrasonic cell grinder extraction (UCGE) method has been developed and applied to extract five anthraquinones (physcion, chrysophanol, emodin, rhein, and aloe-emodin) from radix et rhizoma Rhei. Several parameters of UCGE procedure, including ultrasonic cell grinder running mode, type and volume of extraction solvent and extraction time, were optimized. The determination was preformed on a Waters ultra-performance LC BEH C(18) column using gradient elution system. A baseline separation could be achieved in less than 7.5 min with high resolution. Under the optimized conditions, contents of physcion, chrysophanol, emodin, rhein and aloe-emodin in radix et rhizoma Rhei collected from different cultivated areas were 0-4.22, 0.11-27.64, 0.09-3.49, 0.31-3.31 and 0.13-2.93 mg/g, respectively. Compared with reflux, maceration and ultrasonic bath extractions, the UCGE method was more efficient, faster and easier to be operated, and required lower extraction temperature and less solvent. The results indicated that UCGE was a novel and ideal method for extracting bioactive constituents from plant samples.


Asunto(s)
Antraquinonas/aislamiento & purificación , Cromatografía Liquida/métodos , Medicamentos Herbarios Chinos/química , Ultrasonido , Antraquinonas/análisis , Estándares de Referencia
7.
Planta Med ; 76(2): 159-64, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19670156

RESUMEN

Four new norsesquiterpene derivatives with various rare skeletons: 1 beta-hydroxy-6 alpha-isobutyryloxy-9-noreremophil-7(11),8(10)-dien-8(12)-olide ( 1), 1 beta-acetoxy-6 alpha-isobutyryloxy-9-noreremophil-7(11),8(10)-dien-8(12)-olide ( 2), ligularate ( 3) and 9-oxoplatyphyllide ( 4), as well as four known sesquiterpenes, platyphyllide ( 5), 1-hydroxyplatyphyllide ( 6), 1 alpha-chloro-6 beta-isobutyryloxy-9-oxo-10 beta-hydroxyfuranoeremophilane ( 7), and 1 alpha-chloro-6 beta-angeloyloxy-9-oxo-10 beta-hydroxyfuranoeremophilane ( 8), have been isolated from an extract of the dried roots of Ligularia fischeri (Compositae). The structures of the new compounds were established by spectroscopic methods including extensive 2D NMR techniques ( (1)H- (1)H COSY, HMQC, HMBC and (1)H- (1)H NOESY) and HR-ESI-MS. In addition, a plausible biosyntheticpathway for compounds 1, 2 and 3 is described.


Asunto(s)
Asteraceae/química , Extractos Vegetales/química , Sesquiterpenos/aislamiento & purificación , Asteraceae/metabolismo , Estructura Molecular , Extractos Vegetales/biosíntesis , Raíces de Plantas , Sesquiterpenos/química
8.
J Asian Nat Prod Res ; 12(7): 623-8, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20628943

RESUMEN

Two new 2-alkylchromanones, 2-tricosyl-2,5,7-trihydroxy-chromanone (6) and 2-pentacosyl-2,5,7-trihydroxy-chromanone (7), together with five known 2-alkylated chromones and chromanones (1-5), were isolated from the stems of Polygonum aubertii Henry. The structures of these compounds were established by spectroscopic methods including extensive 1D, 2D NMR ((1)H-(1)H COSY, HSQC, and HMBC), and HR-ESI-MS techniques. In addition, a plausible biosynthetic pathway for these compounds is described.


Asunto(s)
Cromonas/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Polygonum/química , Cromonas/química , Medicamentos Herbarios Chinos/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Tallos de la Planta/química
9.
J Pharm Biomed Anal ; 190: 113413, 2020 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-32781322

RESUMEN

The "multi-component and multi-target" property of traditional Chinese medicine (TCM) makes the quality control more difficult, which remains a key concern hindering the space of progress in its modernization and globalization. This study aims to provide a new strategy to discover quality markers related to the efficacy and stability of TCM based on the bioactive markers finding and differential markers finding, Guan-Xin-Jing capsule (GXJC) was used as a model. Firstly, the UHPLC-QTOF-MS/MS was performed to identify the chemical profiling of GXJC and 148 compounds were unequivocally or tentatively identified. Subsequently, the compounds with relatively low intensity, low oral bioavailability and unsuited drug likeness were removed. In addition, a network based approach by integrating candidate compound genes and disease genes was applied to further filter out the potential active compounds against coronary heart disease (CHD) and finally 7 compounds were identified as the potential bioactive markers. Moreover, to ensure the batch-to-batch consistency of GXJC, an untargeted UHPLC-QTOF-MS/MS based metabolomics approach and multivariate statistical analysis was performed and 5 compounds were identified as the potential differential markers to illustrate the discrepancy among 27 batches of GXJC. Using these strategies above, a total of 11 chemical compounds in GXJC were screened out as quality markers(Q-markers). The information generated with our strategy should be more helpful to guide the selection of the Q-markers and lay the foundation for quality control of TCM.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Metabolómica , Cromatografía Líquida de Alta Presión , Espectrometría de Masas en Tándem
10.
J Nat Prod ; 72(8): 1410-3, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19637864

RESUMEN

Phytochemical investigation of the aerial parts of Oxytropis falcata led to the isolation of three new 24-hydroxyoleanane-type triterpenes (1-3), seven known analogues (4-10), and two rare sesquiterpenoids (12, 13). Compounds 6 and 12 were isolated as new natural products. Triterpenes (5, 6, 8, 11) were isolated from the roots of O. falcata. The structures and relative configurations of these compounds were elucidated by spectroscopic analyses, including 1D and 2D NMR spectroscopy and mass spectrometry, and by comparison of their NMR data with those of related compounds. Single-crystal X-ray diffraction analyses confirmed the structures of 1-4, and the absolute configuration of 3 was evidenced by the incorporation of DMSO (crystallization solvent) in the crystal lattice.


Asunto(s)
Medicamentos Herbarios Chinos/aislamiento & purificación , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/aislamiento & purificación , Oxytropis/química , Triterpenos/aislamiento & purificación , Cristalografía por Rayos X , Medicamentos Herbarios Chinos/química , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Ácido Oleanólico/química , Raíces de Plantas/química , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Triterpenos/química
11.
J Asian Nat Prod Res ; 11(1): 33-7, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19177234

RESUMEN

A new guaiane-type sesquiterpenoid ethoxyvalerianol (1) and one known sesquiterpenoid valeranone (2) together with selina-4,7(11)-diene (3) and selinene (4), which were obtained from (+)-maaliol (5) by decyclization and dehydration, were isolated from Valeriana tangutica. Their structures were elucidated by 1D- and 2D-NMR spectroscopic data and HR-ESI-MS analysis.


Asunto(s)
Antibacterianos/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Plantas Medicinales/química , Pseudomonas aeruginosa/efectos de los fármacos , Sesquiterpenos/aislamiento & purificación , Valeriana/química , Antibacterianos/química , Antibacterianos/farmacología , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Sesquiterpenos Policíclicos , Sesquiterpenos/química , Sesquiterpenos/farmacología
12.
Phytochemistry ; 69(11): 2231-6, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18606426

RESUMEN

Four sesquiterpene lactones including an eremophilenolide dimer, named as biligulaplenolide, 1, 8beta-hydroxy-1-oxo-(14alpha,15alpha eremophil-7(11),9(10)-dien-12,8alpha-olide, 2, 1-hydroxy-2-oxo-(14alpha,15alpha eremophil-1(10),7(11),8(9)-trien-12,8-olide, 3, 4alpha,8beta,9alpha-trihydroxy- 5alphaEta-7(11)-eudesmen-12,8alpha-olide, 4, along with two known ones, 10alpha-hydroxy-1-oxo-eremophil-7(11),8(9)-dien-12,8-olide, 5, and furanoeremophil-1(10)-ene-2,9-dione, 6, were isolated from the underground organs of Ligularia platyglossa (Franch.) Hand.-Mazz. Their structures were elucidated by spectroscopic methods including single-crystal X-ray diffraction analysis (2 and 3). Their in vitro cytotoxicities against seven cancer cell lines (BGC-823, A549, HL-60, B16, SMMC-7721, BEL7402, Hela) were evaluated. Compounds 2, 3, 5 showed cytotoxic activities on HL-60 cancer cells with IC50 in the range of 24.0 to 51.1 microM, whereas compound 3 exhibited only weak cytotoxic activity against the B16, BEL7402 and Hela cancer cells. Flow cytometric analysis indicated that compound 3 induces Hela cells to apoptotic death after 48 h treatment with 0.38 mM of this compound.


Asunto(s)
Asteraceae/química , Sesquiterpenos/química , Sesquiterpenos/toxicidad , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Cristalografía por Rayos X , Humanos , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Estructura Molecular
13.
Zhongguo Zhong Yao Za Zhi ; 31(16): 1324-8, 2006 Aug.
Artículo en Zh | MEDLINE | ID: mdl-17061550

RESUMEN

OBJECTIVE: To clarify the resource of medicinal plants of genus Polygonum s. lat. distributed in Anhui Province. METHOD: Conducting field investigation and consulting related specimens and data. RESULT AND CONCLUSION: The distribution, growing environment and medicinal use of 32 taxa have been clarified. A scientific basis for further study for these medicinal plants has been provided.


Asunto(s)
Analgésicos no Narcóticos/farmacología , Plantas Medicinales/clasificación , Polygonum/clasificación , Fármacos Antidiuréticos/farmacología , China , Conservación de los Recursos Naturales , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Ecosistema , Farmacognosia , Plantas Medicinales/anatomía & histología , Plantas Medicinales/química , Polygonum/anatomía & histología , Polygonum/química
14.
Zhongguo Zhong Yao Za Zhi ; 31(10): 793-7, 2006 May.
Artículo en Zh | MEDLINE | ID: mdl-17048656

RESUMEN

OBJECTIVE: To investigate the species of Ligularia distributed in the northwestern China and their medicinal uses in the local area. METHOD: Field investigation, specimen collection, taxonomic study and datum check were adopted. RESULT: There are 29 species and 1 varieties of Ligularia distributed in the northwestern China, and 18 species of them had been used as folk medicines with the function of resolving phlegm, relieving cough, clearing heat and toxins. CONCLUSION: The northwestern China is abundant in medicinal resource of Ligularia.


Asunto(s)
Asteraceae , Farmacognosia , Plantas Medicinales , Antiasmáticos/aislamiento & purificación , Antiasmáticos/farmacología , Antitusígenos/aislamiento & purificación , Antitusígenos/farmacología , Asteraceae/química , Asteraceae/clasificación , China , Conservación de los Recursos Naturales , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Ecosistema , Humanos , Hipnóticos y Sedantes/aislamiento & purificación , Hipnóticos y Sedantes/farmacología , Plantas Medicinales/química , Plantas Medicinales/clasificación
15.
J Chromatogr A ; 1474: 32-39, 2016 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-27836229

RESUMEN

A kind of solid phase microextraction configuration combining the principles of hollow fiber solid phase microextraction (HF-SPME) and stir bar sorptive extraction (SBSE) is presented. The main feature of HF-SBSE is the use of microporous hollow fiber acting as the carrier and filter, while a thin stainless steel wire and silica microspheres in the lumen of hollow fiber respectively acting as the magnetic stirrer and the dispersed sorbents for the collection and extraction of the target analytes, thus affording extraction process like SBSE. Moreover, the prepared hollow fiber stir bar was applied to direct microextraction and microwave assisted derivatization with N,O-Bis(trimethylsilyl)trifluroacetamide (BSTFA) of four amino acids in rats' urine and cerebrospinal fluid followed by gas chromatography mass spectrometric analysis. The limits of detection for four amino acids were found to be in the range of 0.0003-0.017µgmL-1, and all the analytes did not exhibit any lack of fit. The extraction recoveries using HF-SBSE techniques ranged from 71.8% to 102.3%. The results indicated that hollow fiber stir bar sorptive extraction was a promising technique for the enrichment and direct derivatization of analytes extracted from biological matrices without sample clean-up.


Asunto(s)
Aminoácidos/análisis , Adsorción , Aminoácidos/líquido cefalorraquídeo , Aminoácidos/orina , Animales , Cromatografía de Gases y Espectrometría de Masas , Indicadores y Reactivos , Microesferas , Microondas , Ratas , Estándares de Referencia , Reproducibilidad de los Resultados , Microextracción en Fase Sólida , Solventes , Compuestos de Trimetilsililo
16.
Artículo en Inglés | MEDLINE | ID: mdl-26444336

RESUMEN

An elevated uric acid (UA) in urine or serum can affect renal function and blood pressure, which is an indicator of gout, cardiovascular and renal diseases, hypertension, etc. In this work, a new type of mixed matrix membrane (MMM), based on graphitic carbon nitrides (g-CNs) and hollow fiber (HF), was prepared and combined with solid phase microextraction (SPME) mode to determine UA in urine and serum followed by gas chromatography-mass spectrometry (GC/MS). The porous g-CNs were dispersed in ammonia, and then the exfoliated g-CNs nanosheets were held in the pores of HF by capillary forces and sonification. The prepared g-CNs modified HF (g-CNs-HF) was immersed in biofluid directly to extract UA with SPME mode and the solvent-free mode is convenient for further derivatization and analysis. To achieve the highest extraction efficiency (EF), main extraction and derivatization parameters, such as g-CNs-HF immobilizing time, sonification power and time of extraction, derivatization and desorption time, were optimized. Under the optimum extraction conditions, a favorable linearity of UA was obtained in the range 0.1-200µgmL(-1) with correlation coefficients higher than 0.9990, and the average recoveries at three spiked levels of UA in urine and serum ranged from 80.7% to 121.6%, from 84.7% to 101.1%, respectively. The obtained results demonstrated the developed g-CNs-HF-SPME is a simple, rapid, cost-effective, solvent-free method for the analysis of UA in biofluid.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Grafito/química , Nitrilos/química , Microextracción en Fase Sólida/instrumentación , Ácido Úrico/sangre , Ácido Úrico/orina , Humanos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Difracción de Rayos X
17.
Zhong Yao Cai ; 25(3): 164-6, 2002 Mar.
Artículo en Zh | MEDLINE | ID: mdl-12583157

RESUMEN

OBJECTIVE: To gain a clear idea on the resources of medicinal plants of Polygonum in Gansu. METHODS: Field investigation, specimen collection, taxonomic study, scientific names study and literature retrieval were carried out. RESULTS: The distribution, ecological environment and medicinal parts of 23 species and 7 varieties of Polygonum from Gansu have been clarified. CONCLUSION: The investigation may prove to be useful for the utility and further study of Polygonum in Gansu province.


Asunto(s)
Farmacognosia , Plantas Medicinales , Polygonum , China , Conservación de los Recursos Naturales , Ecosistema , Plantas Medicinales/clasificación , Polygonum/clasificación
18.
J Chromatogr A ; 1216(29): 5467-71, 2009 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-19535086

RESUMEN

News stories about the contamination of milk with melamine in China emerged on Sept 11, 2008, and the situation has since become an international health scare. In this work, a novel analytical method based on enrichment and pretreatment of analytes in the milk sample, hollow fiber sorptive extraction and gas chromatography-mass spectrometry has been developed for the rapid analysis of melamine in the dairy products. In the proposed method, melamine in the fresh milk was extracted by zirconia hollow fiber, enriching on zirconia coating of the hollow fiber, and then analyzed by GC-MS. The method validations including linearity, limit of detection, limit of qualification, recoveries at three different concentrations, precision, and repeatability were investigated. It was found that the proposed method provided linear range from 0.001 to 1000 microg/mL (r(2)=0.9997), low detection limit of 0.001 microg/mL, and preferable recoveries at three different concentrations. The obtained results demonstrated that zirconia hollow fiber combined with GC-MS is a simple, rapid and solvent-free method for the analysis of melamine in the dairy products.


Asunto(s)
Productos Lácteos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Microextracción en Fase Sólida/métodos , Triazinas/análisis , China , Contaminación de Alimentos/análisis , Microextracción en Fase Sólida/instrumentación , Circonio/química
19.
Anal Chim Acta ; 651(2): 182-7, 2009 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-19782809

RESUMEN

The convenient fabrications of titania and zirconia hollow fiber with three-dimensional porous structure using polypropylene hollow fibers as templates were developed. And an analytical method based on enrichment and extraction of analytes in the water sample, hollow fiber sorptive microextraction in combined with gas chromatography has been developed for the rapid analysis of N,N-dimethylacetamide (DMA) in the environmental samples. The results showed that zirconia hollow fiber gave higher extraction performance of DMA than that of titania hollow fiber. The method validations, including linearity, limit of detection, limit of qualification, precision, and repeatability were investigated. Linearity for six-point calibration curve was excellent with zirconia hollow fiber having r2 value greater than 0.9993 at the linearity range of 0.001-1.0 mg mL(-1). In addition, it seems that hollow fiber sorptive extraction is a promising technique for the enrichment and purification of analytes extracted directly from liquid samples without any other pretreatment.


Asunto(s)
Acetamidas/análisis , Cromatografía de Gases/métodos , Crioprotectores/análisis , Microextracción en Fase Sólida/métodos , Titanio/química , Contaminantes Químicos del Agua/análisis , Agua/química , Circonio/química , Adsorción , Polipropilenos/química , Reproducibilidad de los Resultados
20.
Planta Med ; 74(8): 859-63, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18523921

RESUMEN

Four new compounds, 2',6'-dihydroxy-3'-(2-hydroxy-3-methyl-3-butenyl)-4'-methoxychalcone ( 1), 4,6-dihydroxy-7-isobutyryl-5-prenyl-2(3 H)-benzofuranone ( 4), 7- O-(beta- D-glucopyranosyloxy)-5-hydroxy-1(3 H)-isobenzofuranone ( 6) and (2 R,3 S)-3-methyl-2-(5-oxo-2-isopropenylhexyl)-cyclopentanone ( 7), along with thirteen known compounds were isolated from the whole plant of Anaphalis lactea. Their structures were established based on spectroscopic methods including IR, UV, MS, CD, 1 D NMR and 2 D NMR techniques. Compounds 2, 4 - 6 and 8 - 16 were tested for free-radical scavenging properties in the DPPH assays.


Asunto(s)
Antioxidantes/aislamiento & purificación , Asteraceae/química , Plantas Medicinales/química , Benzofuranos/química , Benzofuranos/aislamiento & purificación , Chalconas/química , Chalconas/aislamiento & purificación , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación
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