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1.
Mitochondrial DNA A DNA Mapp Seq Anal ; 28(3): 342-343, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-26713941

RESUMO

The complete nucleotide sequence of the Sinopodophyllum hexandrum Ying chloroplast genome (cpDNA) was determined based on next-generation sequencing technologies in this study. The genome was 157 203 bp in length, containing a pair of inverted repeat (IRa and IRb) regions of 25 960 bp, which were separated by a large single-copy (LSC) region of 87 065 bp and a small single-copy (SSC) region of 18 218 bp, respectively. The cpDNA contained 148 genes, including 96 protein-coding genes, 8 ribosomal RNA genes, and 44 tRNA genes. In these genes, eight harbored a single intron, and two (ycf3 and clpP) contained a couple of introns. The cpDNA AT content of S. hexandrum cpDNA is 61.5%.


Assuntos
Berberidaceae/genética , Genes de Plantas , Genoma de Cloroplastos , Sequência de Bases , DNA de Cloroplastos , Genoma de Planta , Filogenia , Análise de Sequência de DNA
2.
J Chromatogr Sci ; 54(3): 466-71, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26499120

RESUMO

High-speed counter-current chromatography (CCC) was firstly and successfully applied for the preparative separation and purification of alkaloids from crude extract of Hypecoum leptocarpum. After the measurement of partition coefficient of five target alkaloids in the two-phase solvent systems, the CCC was performed well with a two-phase solvent system composed of tetrachloromethane-chloroform-methanol-0.1 M HCl at a volume ratio of 1.5 : 2.5 : 3 : 2 (V/V/V/V). The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. From 120 mg crude extract, 5 mg leptopidine, 32 mg oxohydrastinine, 27 mg (-)-N-methylanadine, 7 mg N-feruloyltyramine and 3 mg hypecoleptopine could be successfully separated. The amides alkaloid, N-feruloyltyramine, was firstly separated from H. leptocarpum. High-performance liquid chromatography analysis showed that the purity of each of the five target alkaloids was over 92%. Their chemical structures were confirmed by (1)H-NMR and (13)C-NMR data.


Assuntos
Alcaloides/isolamento & purificação , Ácidos Cumáricos/isolamento & purificação , Distribuição Contracorrente/métodos , Isoquinolinas/isolamento & purificação , Papaveraceae/química , Extratos Vegetais/química , Tiramina/análogos & derivados , Tetracloreto de Carbono , Clorofórmio , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente/instrumentação , Ácido Clorídrico , Metanol , Estrutura Molecular , Solventes , Tiramina/isolamento & purificação
3.
Food Chem ; 194: 296-303, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26471558

RESUMO

Anthocyanins are the main compounds in Nitraria tangutorun Bobr. The enrichment and purification of anthocyanins on macroporous resins were investigated. Regarding anthocyanin purification, static adsorption and desorption were studied. The optimal experimental conditions were the following: resin type: X-5; static adsorption time: 6h; desorption solution: ethanol-water-HCl (80:19:1, V/V/V; pH 1); desorption time: 40min. Furthermore, the in vitro and in vivo biological activities of the anthocyanins were evaluated. The anthocyanins showed ideal scavenging effects on free radicals in vitro, especially on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical (OH). In the animal experiment, blood lipid metabolism of hyperlipidemia rats was regulated by anthocyanin contents. The superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) of hyperlipidemia rats were also improved by anthocyanins. These results showed that anthocyanins from N. tangutorun Bobr. fruits had potential biological activities in vivo as well as in vitro.


Assuntos
Antocianinas/farmacologia , Antioxidantes/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Hiperlipidemias/tratamento farmacológico , Zygophyllaceae/química , Animais , Antocianinas/isolamento & purificação , Antocianinas/uso terapêutico , Antioxidantes/isolamento & purificação , Antioxidantes/uso terapêutico , Compostos de Bifenilo/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/uso terapêutico , Radicais Livres/química , Frutas/química , Radical Hidroxila/química , Hiperlipidemias/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/sangue , Oxirredução , Picratos/química , Extratos Vegetais/química , Ratos , Ratos Wistar , Superóxido Dismutase/sangue
4.
J Chromatogr Sci ; 54(3): 479-85, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26598549

RESUMO

High efficiency and less solvent consumption are the essential requirements of high-speed countercurrent chromatography (HSCCC), especially for the large-scale preparation. In this study, an efficient HSCCC strategy with consecutive sample injection was successfully developed to rapidly separate and purify rhaponticin and rhapontigenin from the seeds of the Chinese medicinal herb fenugreek (Trigonella foenum-graecum L.). The effective separation was achieved using n-hexane-ethyl acetate-methanol-water (1:4:2:6, v/v/v/v) as the two-phase solvent system, in which the mobile phase was eluted at an optimized flow rate of 2.2 mL/min and a revolution speed of 850 rpm. After consecutively loading four identical fenugreek samples, each containing 120 mg, HSCCC separation yielded 146.4 mg of rhaponticin and 174.8 mg of rhapontigenin with purities of 98.6 and 99.1%, respectively, as determined by high-performance liquid chromatography at 320 nm. Their chemical structures were identified using UV spectroscopy, (1)H-NMR and (13)C-NMR. The HSCCC method with consecutive sample injection allowed faster separation and produced less solvent waste, suggesting that it is an efficient way to rapidly separate and purify natural products on a large scale.


Assuntos
Distribuição Contracorrente/métodos , Extração Líquido-Líquido/métodos , Sementes/química , Estilbenos/isolamento & purificação , Trigonella/química , Acetatos , Cromatografia Líquida de Alta Pressão , Análise de Injeção de Fluxo , Hexanos , Metanol , Extratos Vegetais/química , Solventes , Água
5.
J Sep Sci ; 38(23): 4063-70, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26544947

RESUMO

A method that involved the combination of pH-zone-refining counter-current chromatography and semipreparative reversed-phase liquid chromatography has been established for the preparative separation of alkaloids from Hypecoum leptocarpum. From 1.2 g of crude sample, 31 mg N-feruloyltyramine, 27 mg oxohydrastinine, 47 mg hydroprotopine, 25 mg leptopidine, and 18 mg hypecocarpine have been obtained. The structure of the new compound, hypecocarpine, is confirmed based on the analysis of spectroscopic data, including NMR, UV, and IR spectroscopy and positive electrospray ionization mass spectrometry. The known chemical structures were characterized on the basis of (1) H and (13) C NMR spectroscopy. The purities of the five alkaloids are all over 92.7% as determined by high-performance liquid chromatography. The alkaloids' cytotoxicity in breast cancer cells is assessed by using a Cell Counting Kit assay and their inhibitory effect on fatty acid synthase expression is assessed by a Western blot assay. These results suggest that leptopidine could suppress growth and induce cytotoxicity in breast cancer cells and that the cytotoxicity of leptopidine may be related to its inhibitory effect on fatty acid synthase expression.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Ácido Graxo Sintases/antagonistas & inibidores , Papaveraceae/química , Alcaloides/química , Western Blotting , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Immunoblotting , Medicina Tradicional Tibetana
6.
J Chromatogr Sci ; 53(8): 1341-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25744248

RESUMO

High-speed counter-current chromatography (HSCCC) was successfully applied for the preparative separation and purification of N-feruloyl serotonin (NF) and N-(p-coumaroyl) serotonin (NP) from safflower seed meal. After the measurement of partition coefficient of the two target compounds in the two-phase solvent systems, the HSCCC was performed well with a two-phase solvent system composed of CHCl3-methanol-0.1 M HCl at a volume ratio of 1 : 1 : 1, v/v. The upper phase was used as stationary phase and the lower phase was used as mobile phase. Under the optimized condition, 7.5 mg NF and 6.9 mg NP were separated from 40 mg crude sample with the purity of 98.8 and 97.3%, respectively. The structures of the isolated compounds were identified by (1)H NMR and (13)C NMR.


Assuntos
Carthamus tinctorius/química , Distribuição Contracorrente/métodos , Sementes/química , Serotonina/análogos & derivados , Ressonância Magnética Nuclear Biomolecular , Serotonina/análise , Serotonina/química , Serotonina/isolamento & purificação
7.
Artigo em Inglês | MEDLINE | ID: mdl-25770790

RESUMO

A method of using high-speed counter-current chromatography (HSCCC) for preparative isolation and purification of oligostilbenes from the ethanol extracts of seed kernel of Iris lactea Pall. var. chinensis (Fisch.) Koidz was established in this study. Four oligostilbenes were successfully separated and purified by HSCCC with two sets of two-phase solvent system, n-hexane-ethyl acetate-methanol-water (3:6:4.2:5.5, v/v/v/v) in the head-to-tail elution mode for the first separation to mainly isolate vitisin A (58 mg), ɛ-viniferin (76 mg) and peak II (43 mg) from 300 mg of the crude ethanol extracts, and then light petroleum-ethyl acetate-methanol-water (5:5:3:6, v/v/v/v) in the tail-to-head elution mode for the second separation to isolate vitisin B (52 mg) and vitisin C (11 mg) from 100mg of peak II. The purities of the isolated four oligostilbenes were all over 95.0% as determined by HPLC. Vitisin A, vitisin B and vitisin C, resveratrol tetramers, were isolated from Iris lactea for the first time. The preparation of crude sample was simple and the HSCCC method for the isolation and purification of four oligostilbenes was rapid, efficient and economical.


Assuntos
Benzopiranos/isolamento & purificação , Distribuição Contracorrente/métodos , Gênero Iris/química , Extratos Vegetais/química , Sementes/química , Estilbenos/isolamento & purificação , Benzopiranos/química , Modelos Moleculares , Estilbenos/química
8.
Artigo em Inglês | MEDLINE | ID: mdl-24055753

RESUMO

High-speed counter-current chromatography (HSCCC) was successfully applied for the first time to isolate and purify four cis-trans isomers of coumaroylspermidine analogs from Safflower. HSCCC separation was achieved with a two-phase solvent system composed of chloroform-methanol-water (1:1:1, v/v/v) with the upper phase as the mobile phase. In a single run, a total of 1.3mg of N(1), N(5), N(10)-(E)-tri-p-coumaroylspermidine (EEE), 4.4mg of N(1)(E)-N(5)-(Z)-N(10)-(E)-tri-p-coumaroylspermidine (EZE), 7.2mg of N(1)(Z)-N(5)-(Z)-N(10)-(E)-tri-p-coumaroylspermidine (ZZE), and 11.5mg of N(1),N(5),N(10)-(Z)-tri-p-coumaroylspermidine (ZZZ) were obtained from 100mg of crude sample. High Performance Liquid Chromatography (HPLC) analysis showed that the purities of these four components are 95.5%, 98.1%, 97.5% and 96.2%, respectively. The chemical structures were identified by ESI-MS, (1)H NMR and (13)C NMR.


Assuntos
Carthamus tinctorius/química , Ácidos Cumáricos/isolamento & purificação , Distribuição Contracorrente/métodos , Espermidina/análogos & derivados , Espermidina/isolamento & purificação , Ácidos Cumáricos/análise , Ácidos Cumáricos/química , Isomerismo , Modelos Moleculares , Extratos Vegetais/química , Espermidina/análise , Espermidina/química
9.
Phytochem Anal ; 23(6): 684-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22585637

RESUMO

INTRODUCTION: The official rhubarb species have frequently been investigated for their hydroxyanthraquinone components and associated pharmacological properties. However, other unofficial rhubarb species were rarely studied until polyhydroxystilbenes (PHS), which commonly occur in the unofficial rhubarb, revealed a range of potential bioactivities. Hence, there has been increasing interest in the efficient preparation of high-purity PHS for pharmacological and clinical trials. OBJECTIVE: To develop a suitable method for large-scale preparative separation of PHS from the rhizome of Rheum likiangense Sam. by high-speed counter-current chromatography (HSCCC). RESULTS: Two PHS compounds were isolated successfully within 440 min using a solvent system consisting of methanol:n-butanol:chloroform:water (2:0.5:3:3, v/v/v/v). Eighty-four milligrams of desoxyrhaponticin with 98.2% purity and 148 mg of rhaponticin with 95.3% purity were respectively yielded from 1.5 g of crude extract in the single, one-step operation. CONCLUSION: An optimised HSCCC method has been established for large-scale preparative separation of PHS compounds from Rheum likiangense Sam.


Assuntos
Cromatografia Líquida/métodos , Rheum/química , Estilbenos/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Glucosídeos , Rizoma/química , Solventes
10.
Anal Chim Acta ; 609(1): 66-75, 2008 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-18243875

RESUMO

A novel labeling reagent 1-(2-naphthyl)-3-methyl-5-pyrazolone (NMP) coupled with capillary electrophoresis (CE) with DAD detection for the determination of carbohydrates has been developed. The chromophore in the 1-phenyl-3-methyl-5-pyrazolone (PMP) reagent is replaced by naphthyl functional group, which results in a reagent with very high molar absorptivity (epsilon251 nm = 5.58 x 10(4) L mol(-1) cm(-1)). This permits NMP-labeled carbohydrates to be detected with UV absorbance in standard 50-mum-i.d. fused silica capillaries by zone electrophoresis. In this mode, nanomolar concentrations of detection limits are obtained. The method for the derivatization of carbohydrates with NMP is simplified. The derivatization reaction is rapid and mild in the presence of ammonia catalyst without further transfer steps. Nine monosaccharide derivatives such as mannose, galacturonic acid, glucuronic acid, rhamnose, glucose, galactose, xylose, arabinose and fucose can successfully be detected in CE mode. Good reproducibility can be obtained with relative standard deviation (R.S.D.) values of the migration times and peak area, respectively, from 0.44 to 0.48 and from 3.2 to 4.8. Furthermore, the developed method has been successfully applied to the analysis of carbohydrates in the hydrolyzed rape bee pollen samples.


Assuntos
Carboidratos/análise , Carboidratos/química , Eletroforese Capilar/métodos , Naftalenos/química , Pirazolonas/química , Espectrofotometria/métodos , Raios Ultravioleta , Animais , Abelhas/química , Boratos/química , Ligação de Hidrogênio , Hidrólise , Íons/química , Estrutura Molecular , Pólen/química , Espectrometria de Massas por Ionização por Electrospray , Temperatura , Fatores de Tempo
11.
Talanta ; 72(3): 914-25, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19071704

RESUMO

A pre-column derivatization method for the sensitive determination of amines using a labeling reagent 2-(11H-benzo[a]-carbazol-11-yl) ethyl chloroformate (BCEC-Cl) followed by high-performance liquid chromatography with fluorescence detection has been developed. Identification of derivatives was carried out by LC/APCI/MS in positive-ion mode. The chromophore of 1,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC-Cl) reagent was replaced by 2-(11H-benzo[a]-carbazol-11-yl) ethyl functional group, which resulted in a sensitive fluorescence derivatizing reagent BCEC-Cl. BCEC-Cl could easily and quickly label amines. Derivatives were stable enough to be efficiently analyzed by HPLC and showed an intense protonated molecular ion corresponding m/z [M+H](+) under APCI/MS in positive-ion mode. The collision-induced dissociation of the protonated molecular ion formed characteristic fragment ions at m/z 261.8 and m/z 243.8 corresponding to the cleavages of CH(2)O-CO and CH(2)-OCO bonds. Studies on derivatization demonstrated excellent derivative yields over the pH 9.0-10.0. Maximal yields close to 100% were observed with three- to four-fold molar reagent excess. In addition, the detection responses for BCEC-derivatives were compared to those obtained using 1,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC-Cl) and 9-fluorenyl methylchloroformate (FMOC-Cl) as labeling reagents. The ratios I(BCEC)/I(BCEOC)=1.94-2.17 and I(BCEC)/I(FMOC)=1.04-2.19 for fluorescent (FL) responses (here, I was relative fluorescence intensity). Separation of the derivatized amines had been optimized on reversed-phase Eclipse XDB-C(8) column. Detection limits calculated from 0.50pmol injection, at a signal-to-noise ratio of 3, were 1.77-14.4fmol. The relative standard deviations for within-day determination (n=11) were 1.84-2.89% for the tested amines. The mean intra- and inter-assay precision for all amines levels were <3.64% and 2.52%, respectively. The mean recoveries ranged from 96.6% to 107.1% with their standard deviations in the range of 0.8-2.7. Excellent linear responses were observed with coefficients of >0.9996.

12.
Se Pu ; 24(5): 456-61, 2006 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-17165537

RESUMO

A simple and sensitive method for the determination of long-chain free fatty acids (FFAs) using 1-[2-(p-toluenesulfonate) ethyl]-2-phenylimidazole [4, 5-f] 9, 10-phenanthrene (TSEPIP) as pre-column derivatization reagent by reversed-phase high performance liquid chromatography with fluorescence detection and mass spectrometric identification was developed. Eleven long-chain (C20-C30) FFA derivatives were separated on Eclipse XDB-C8 column with a good baseline resolution. Studies on derivatization conditions indicate that FFA reacts rapidly and smoothly with TSEPIP in the presence of K2CO3, catalyst at 90 degrees C in N, N-dimethylformamide solvent to give the corresponding sensitively fluorescent derivatives with maximal yields close to 100% with a 5-fold molar reagent excess. The identification of 11 FFA derivatives was carried out by online post-column mass spectrometry with atmospheric pressure chemical ionization source in positive-ion mode. The contents of 11 FFAs in soil and three bryophytes (Homomallium connexum (Card.) Broth., Actinothuidium hookeri, Neckera pennata) were determined. The results indicate that the bryophyte plants enrich an abundance of FFAs from soil. The excitation and emission wavelengths of fluorescence detection were set at 260 nm and 380 nm, respectively. Linear correlation coefficients for the most FFA derivatives were higher than 0.9996, and the detection limits (at signal-to-noise of 3:1) were 26.19-76.67 fmol. The method is sensitive and reproducible for the determination of long-chain FFAs in real samples.


Assuntos
Ácidos Graxos/análise , Imidazóis/síntese química , Fenantrenos/síntese química , Briófitas/química , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Imidazóis/química , Indicadores e Reagentes , Espectrometria de Massas , Fenantrenos/química , Sensibilidade e Especificidade , Solo/análise , Espectrometria de Fluorescência
13.
J Ethnopharmacol ; 98(1-2): 31-5, 2005 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-15763361

RESUMO

Concentrations of seven phytochemical constituents (swertiamarin, mangiferin, swertisin, oleanolic acid, 1,5,8-trihydroxy-3-methoxyxanthone, 1,8-dihydroxy-3,7-dimethoxyxanthone and 1,8-dihydroxy-3,5-dimethoxyxanthone) of "ZangYinChen" (Swertia mussotii, a herb used in Tibetan folk medicine) were determined and compared in plants collected from naturally distributed high-altitude populations and counterparts that had been artificially cultivated at low altitudes. Levels of mangiferin, the most abundant active compound in this herb, were significantly lower in cultivated samples and showed a negative correlation with altitude. The other constituents were neither positively nor negatively correlated with cultivation at low altitude. Concentrations of all of the constituents varied substantially with growth stage and were highest at the bud stage in the cultivars, but there were no distinct differences between flowering and fruiting stages in this respect.


Assuntos
Agricultura/métodos , Geografia , Medicina Tradicional Tibetana , Swertia/química , Altitude , Avaliação Pré-Clínica de Medicamentos/métodos , Flores/química , Glucosídeos/química , Glucosídeos/metabolismo , Glucosídeos Iridoides , Iridoides/química , Iridoides/metabolismo , Ácido Oleanólico/análise , Ácido Oleanólico/química , Fenômenos Fisiológicos Vegetais , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Pironas/química , Pironas/metabolismo , Sementes/química , Swertia/crescimento & desenvolvimento , Swertia/metabolismo , Fatores de Tempo , Xantonas/química , Xantonas/metabolismo
14.
Se Pu ; 22(1): 38-40, 2004 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15712943

RESUMO

A simple and accurate method for the determination of haleniaside and demethoxyhaleniaside in Halenia ellipitica D. Don. materials and patent medicines with high performance liquid chromatography (HPLC) was developed. The two components were extracted from powdered samples with methanol. The resultant extract was separated within 45 min on a VP-ODS C18 column (4.6 mm i.d. x 250 mm, 5 microm) under gradient elution with a mixture of acetonitrile-phosphate buffer at a flow rate of 1.0 mL/min. The detection wavelength was 254 nm and the injection volume was 20 microL. Under gradient elution program the volume fractions of acetonitrile in mobile phase were as follows: 0 - 5 min, 12%; 5 - 15 min, 12% - 15% ; 15 - 40 min, 15% - 35%. Both haleniaside and dehydrohaleniaside have good linearity in the ranges of 0.68 - 3.40 g/L and 0.36 - 1.8 g/L with correlation coefficients of 0.999 8 and 0.999 0 respectively. This method has been successfully applied to the analysis of Halenia ellipitica D. Don materials and related patent medicines.


Assuntos
Medicamentos de Ervas Chinesas/análise , Gentianaceae/química , Xantonas/análise , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Xantonas/isolamento & purificação
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