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1.
J Chromatogr A ; 1664: 462794, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-34998026

RESUMO

A sensitive capillary electrophoresis strategy was developed by combining salting-out assisted liquid-liquid extraction and online three-step stacking to detect trace quantities of antitumour indole alkaloids in complex biological samples. The proposed strategy fully exploits these two technologies such that extraction, online stacking and separation are combined in a fast and efficient manner. First, salting-out assisted liquid-liquid extraction was used to extract three indole alkaloids (vinblastine sulfate, catharanthine sulfate and vindoline) from complex biomasses. An appropriate volume of acetonitrile (ACN) was mixed with a faecal aqueous solution to precipitate proteins. The mixed solution was vortexed, followed by the addition of ammonium sulfate ((NH4)2SO4) to induce two-phase separation. Alkaloids were effectively extracted into the organic phase, which was then subjected to capillary electrophoresis (CE) analysis. The sensitivity of capillary electrophoresis was effectively improved by online three-step stacking. Good linearity of the calibration curve for each indole alkaloid was obtained in the concentration range of 0.1-1 µg/mL. Under optimal conditions, the sensitivity of ordinary injection was increased by up to 2366-fold, confirming the applicability of the proposed strategy for the sensitive determination of trace indole alkaloids in complex biological samples.


Assuntos
Alcaloides , Vimblastina , Eletroforese Capilar , Extração Líquido-Líquido , Cloreto de Sódio
2.
J Sep Sci ; 44(17): 3229-3236, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34240804

RESUMO

Semen of Cuscuta chinensis has been reported to have an anti-osteoporosis effect, however, the components which account for the anti-osteoporosis effect have not been clarified. In this work we propose a biochemometrics strategy that integrates quantitation, anti-osteoporosis evaluation in zebrafish, and grey relationship analysis for the identification of anti-osteoporosis components from the semen of Cuscuta chinensis. In the beginning, a precise and accurate liquid chromatography-tandem mass spectrometry method was established for simultaneous quantitation of seven major components in crude and salt-processed Cuscuta chinensis. The mode of multiple reaction monitoring was used. Chloramphenicol was selected as the internal standard. The method showed good linearity and repeatability. The recovery rates of each component ranged from 95.4 to 103.9%. The precisions of intra-day and inter-day were all within 5.0%. The method was then applied for quantitation of the seven major components in 11 batches of crude and salt-processed Cuscuta chinensis. Subsequently, the anti-osteoporosis effects of crude and salt-processed Cuscuta chinensis were evaluated in zebrafish. Principle component analysis, grey relationship analysis, and partial least squares regression were applied for deciphering the relationship between the contents of seven major components and the anti-osteoporosis effects. Hyperin, p-hydroxycinnamic acid, and astragalin were found to be the major anti-osteoporosis components.


Assuntos
Cuscuta/química , Medicamentos de Ervas Chinesas/uso terapêutico , Osteoporose/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Sêmen/química , Animais , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicina Tradicional Chinesa , Análise Multivariada , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Sais/química , Espectrometria de Massas em Tandem , Ondas Ultrassônicas , Peixe-Zebra
3.
J Sep Sci ; 44(13): 2655-2662, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33884745

RESUMO

To avoid irreversible stationary phase adsorption and tedious and time-consuming separation steps, high-speed countercurrent chromatography was employed for the preparative separation of anti-tumor compound antroquinonol from solid fermentation culture of Antrodia camphorata for the first time. A Box-Behnken experimental design, based on three parameters including liquid-to-solid ratio, extraction time, and extraction temperature, was applied to optimize the ultrasonic extraction procedure. The optimal extraction condition was set as follows: liquid-to-solid ratio: 49.57:1; extraction time: 55.76 min; extraction temperature was arranged as 44.21°C. Meanwhile, an optimized solvent system containing petroleum ether, ethyl acetate, methanol, and water (4:1:4:1, v/v/v/v) was selected for the preparative separation of antroquinonol at a flow rate of 2.0 mL/min. The yield of isolated antroquinonol was determined to be 6.0 mg from 0.67 g of ethyl acetate extracts. The isolated antroquinonol was elucidated by ultra-high-performance liquid chromatography-tandem mass spectrometry, and NMR spectroscopy, and by comparison with literature data. The purity of isolated antroquinonol was determined to be 97.12%. This study confirmed that high-speed countercurrent chromatography was powerful and cost-effective for the preparative separation of the high-potently anti-tumor compound antroquinonol from solid fermentation culture of A. camphorata.


Assuntos
Antineoplásicos/isolamento & purificação , Distribuição Contracorrente/métodos , Polyporales/química , Ubiquinona/análogos & derivados , Extratos Vegetais/química , Ubiquinona/biossíntese , Ubiquinona/isolamento & purificação
4.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(11): 1607-1614, 2020 Nov 30.
Artigo em Chinês | MEDLINE | ID: mdl-33243733

RESUMO

OBJECTIVE: To explore genetic mutation types and their correlation with clinical phenotypes in Uighur patients with aortic disease in Kashgar (Xinjiang Uighur Autonomous Region, China). METHODS: We examined 37 pathogenic genes in 19 Uighur families with aortic diseases including Marfan syndrome from Kashgar using next generation sequencing, and the results were confirmed by Sanger sequence in the first relatives. RESULTS: This study included 19 families with aortic diseases, in whom a total of 23 variants were identified, and 11 (57.89%) probands had one or more variants. Among them, definite pathogenic mutation was detected in one patient (5.26%), variants of uncertain significance (VUS) were found in 8 (42.11%), and benign/likely benign variants were detected in 7 (36.84%). The 23 variants identified included one (5.26%) pathogenic variant, 14 (60.87%) VUS, and 8 (34.78%) benign/likely benign variants. The 14 VUS were analyzed by prediction with SIFT and Polyphen2 HDIV, which identified 6 (42.86%) variants as deleterious/possibly damaging; all the 8 benign/likely benign variants were predicted to be deleterious/possibly damaging. CONCLUSIONS: We detected 23 genetic variants in the 19 Uighur families with aortic diseases, and 22 of these variants remain to be verified by more patient data in future studies.


Assuntos
Doenças da Aorta , Sequenciamento de Nucleotídeos em Larga Escala , China , Predisposição Genética para Doença/genética , Humanos , Mutação , Fenótipo
5.
J Sep Sci ; 43(3): 681-688, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31714009

RESUMO

Acetyltropic acid is an important synthetic intermediate for preparation of tropane alkaloid derivatives, which can be used as anticholinergic drugs, deliriants, and stimulants. In the present work, acetyltropic acid was successfully enantioseparated by countercurrent chromatography using sulfobutyl ether-ß-cyclodextrin as chiral selector. A biphasic solvent system composed of n-butyl acetate/n-hexane/0.1 mol/L citrate buffer at pH = 2.2 containing 0.1 mol/L of sulfobutyl ether-ß-cyclodextrin (7:3:10, v/v) was selected, which produced a suitable distribution ratio DS  = 1.14, DR  = 2.31 and a high enantioseparation factor α = 2.03. Baseline separation was achieved for preparative enantioseparation of 50 mg of racemic acetyltropic acid. A method for chiral analysis of acetyltropic acid by conventional reverse phase liquid chromatography with hydroxylpropyl-ß-cyclodextrin as mobile phase additive was established, and formation constants of inclusion complex were determined. It was found that different substituted ß-cyclodextrin should be selected for enantioseparation of acetyltropic acid by countercurrent chromatography and reverse phase liquid chromatography.


Assuntos
beta-Ciclodextrinas/química , Distribuição Contracorrente , Conformação Molecular , Estereoisomerismo
6.
Zhongguo Zhong Yao Za Zhi ; 44(19): 4158-4164, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31872693

RESUMO

Insulin resistance,as the main link in the pathogenesis of type 2 diabetes mellitus( T2 DM),runs through the whole process of occurrence and development of T2 DM and is closely related to the insulin receptor signaling pathway. Insulin stimulation causes autophosphorylation of the insulin receptor( IR),which then activates tyrosine phosphorylation of insulin receptor substrate( IRS).Phosphorylation of IRS can induce and activate phosphatidylinositol 3-kinase( PI3 K),subsequently activate downstream 3-phosphoinositide-dependent protease 1( PDK1) and Akt/PKB,and finally promote expression and translocation of glucose transporter 4 to increase glucose uptake of insulin-sensitive tissues and alleviate insulin resistance. Currently,oral hypoglycemic agents for clinical treatment of T2 DM have different side effects on the human body. Traditional Chinese medicine not only has a wide range of sources and abundant types,but also has comprehensive multi-component,multi-link and multi-target effects,showing unique advantages in the treatment of diabetes. In recent years,more and more researchers at home and abroad pay attention to the active ingredients in traditional Chinese medicine for alleviating insulin resistance. In this paper,we would summarize the active hypoglycemic ingredients of traditional Chinese medicine associated with the insulin receptor signaling pathway,which may provide some theoretical guidance for the development of traditional Chinese medicine in the treatment of diabetes.


Assuntos
Hipoglicemiantes/uso terapêutico , Resistência à Insulina , Medicina Tradicional Chinesa , Receptor de Insulina/metabolismo , Diabetes Mellitus Tipo 2 , Humanos , Insulina , Proteínas Substratos do Receptor de Insulina , Fosfatidilinositol 3-Quinases , Fosforilação , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais
7.
Fitoterapia ; 137: 104190, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31163199

RESUMO

The genus Tripterygium belongs to the family Celastraceae, and contains three species, i.e. Tripterygium wilfordii Hook. F, Tripterygium hypoglaucum (Levl.) Hutch. and Tripterygium regelii Sprague et Takeda. All three species are reported to have excellent medicinal properties that help to cure rheumatoid arthritis, nephrotic syndrome, systemic lupus erythematosus and widely used as a folk medicine in China. Phytochemical studies have led to discovering more than 500 secondary metabolites in this genus, including five main types: sesquiterpenoids, diterpenes, triterpenoids, flavonoids, lignans. This work provides structurally grouping statistic of 198 secondary metabolites of Tripterygium species published from 2008 to the present, as well as pharmacological knowledges in the past five years. The information will be helpful for developing the new discoveries of medicinal value related to the genus Tripterygium.


Assuntos
Tripterygium/química , Tripterygium/classificação , Animais , Anti-Inflamatórios/química , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Antivirais/química , Diterpenos/química , Flavonoides/química , Humanos , Imunossupressores/química , Lignanas/química , Estrutura Molecular , Fármacos Neuroprotetores/química , Compostos Fitoquímicos/química , Metabolismo Secundário , Sesquiterpenos/química , Triterpenos/química
8.
J Food Sci ; 84(4): 754-761, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30908644

RESUMO

Four polysaccharide fractions (P-1: 71.40%, P-2: 1.95%, P-3: 1.14%, P-4: 1.64%) were isolated from crude Polygonatum sibiricum polysaccharide (PSP), processed by water extraction, ethanol precipitation, and further separated with diethylaminoethyl cellulose-52 anion-exchange chromatography. Their molecular weights and monosaccharide compositions were characterized by high performance gel chromatography with evaporative light scattering detector and ultraviolet-visible detector. The antioxidant activity of four polysaccharides fractions were assessed by the electron transfer menchanism (DPPH, ferric reducing power, and ABST assays) and chelation of transition metals (Fe2+ and Cu2+ chelation ability). The highest content fraction P-1 exhibited the lowest antioxidant activity, and the ranking of antioxidant capacity was P-4 > P-3 > P-2 > PSP > P-1. After processed by microwave-assisted degradation, the molecular weight of P-1 was decreased from 2.99 × 105 to 2.33 × 103 Da, while the antioxidant activity of degraded P-1 was about eightfold higher than natural P-1. These results indicated that the proposed microwave-assisted degradation approach was an efficacious methodology to improve their bioactivity by lower the molecular weight of polysaccharides. PRACTICAL APPLICATION: This study provided an environmentally friendly, convenient and efficient microwave-assisted degradation technology to process the neutral polysaccharides from Polygonatum sibiricum. The results could be used for the development and utilization of various plant polysaccharides as a kind of food supplement in our daily life.


Assuntos
Antioxidantes/química , Antioxidantes/metabolismo , Polygonatum/química , Polissacarídeos/química , Polissacarídeos/metabolismo , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/química , Cromatografia em Gel , Micro-Ondas , Peso Molecular , Picratos/química , Polissacarídeos/isolamento & purificação
9.
Biomed Chromatogr ; 33(7): e4534, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30874318

RESUMO

This study established a rapid and reliable approach using liquid chromatography-tandem mass spectrometry for the simultaneous determination of cinnamic acid, vanillic acid and protocatechuic acid in rat plasma. This is the first report on a comparative pharmacokinetic study of dispensing granules and standard decoction of Cinnamomum cassia twigs in rats. After liquid-liquid extraction by ethyl acetate, the plasma samples were subjected to LC-MS/MS for multiple reaction monitoring. The standard curves showed good linear regression (r2 > 0.9991) in the range of 10.0-16000 ng/mL. The intra- and inter-day accuracy and precision were found to be within 15% of the nominal concentration. The recoveries of the three phenolics ranged from 88.7 to 105.7%. Finally, this approach was successfully applied to pharmacokinetic analysis of the three phenolics after oral administration of standard decoction and dispensing granules of C. cassia twigs in rats. Although the values of AUC0-t of vanillic acid and protocatechuic acid in standard decoction group were larger than those of the dispensing granule group, no significant difference was observed for the two groups. Of note, the elimination rates of vanillic acid were slower in the standard decoction group than the dispensing granule group.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cinnamomum aromaticum/química , Medicamentos de Ervas Chinesas/química , Polifenóis/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Estabilidade de Medicamentos , Limite de Detecção , Modelos Lineares , Masculino , Polifenóis/química , Polifenóis/farmacocinética , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
10.
J Chromatogr A ; 1444: 99-105, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-27036211

RESUMO

Selective separation of chemical components from seven kinds of volatile oil by countercurrent chromatography with three types of cyclodextrins as selective reagent was investigated in this work. Preparative separation of chemical components from volatile oil is generally quite challenging due to their extremely complexity of the composition. A biphasic solvent system n-hexane-0.10 mol L(-1) cyclodextrin (1:1, v/v) was selected for separation of components from volatile oil and three types of cyclodextrins were investigated, including ß-cyclodexrin, methyl-ß-cyclodexrin and hydroxypropyl-ß-cyclodexrin. All kinds of volatile oils are from seven kinds of traditional Chinese herb. Results showed that some chemical components could be well separated with high purity from each kind of volatile oil using different type of cyclodextrin as selective reagent. For example, germacrone and curcumenone could be selectively separated from volatile oil of Curcumae Rhizoma with methyl-ß-cyclodexrin and hydroxypropyl-ß-cyclodexrin as selector respectively, and other five components were selectively separated from volatile oil of Chuanxiong Rhizoma, Myristicae Semen, Aucklandiae Radix and Angelicae Sinensis Radix by countercurrent chromatography with different cyclodexrin as selective reagent. Separation mechanism for separation of components from volatile oil by countercurrent chromatography with cyclodextrin as selective reagent was proposed. Peak resolution of the present separation method could be greatly influenced by the chemical compositions of volatile oil.


Assuntos
Técnicas de Química Analítica/métodos , Distribuição Contracorrente , Ciclodextrinas/química , Óleos Voláteis/química , Curcuma/química , Hexanos/química , Rizoma/química
11.
Oncol Lett ; 10(2): 754-760, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26622565

RESUMO

It was originally thought that no single routine blood test result would be able to indicate whether or not a patient had cancer; however, several novel studies have indicated that the median survival and prognosis of cancer patients were markedly associated with the systemic circulation features of cancer patients. In addition, certain parameters, such as white blood cell (WBC) count, were largely altered in malignant tumors. In the present study, routine blood tests were performed in order to observe the change of blood cells in tumor-bearing mice following the implantation of 4T1 breast cancer cells into the mammary fat pad; in addition, blood flow in breast tumor sites was measured indirectly using laser Doppler perfusion imaging (LDPI), in an attempt to explain the relevance between the blood circulation features and the growth or metastasis of breast cancer in mice model. The LDPI and blood test results indicated that the implantation of 4T1 breast cancer cells into BALB/c mice led to thrombosis as well as high WBC count, high platelet count, high plateletcrit and low blood perfusion. Following implantation of the 4T1 cells for four weeks, the lung metastatic number was determined and the Pearson correlation coefficient revealed that the number of visceral lung metastatic sites had a marked negative association with the ratio of basophils (BASO%; r=-0.512; P<0.01) and the mean corpuscular hemoglobin was significantly correlated with primary tumor weight (r=0.425; P<0.05). In conclusion, the results of the present study demonstrated that tumor growth led to thrombosis and acute anemia in mice; in addition, when blood BASO% was low, an increased number of lung metastases were observed in tumor-bearing mice.

12.
J Sep Sci ; 38(12): 2085-92, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25864388

RESUMO

The chromatographic retention mechanism describing relationship between retention factor and concentration of Cu(2+) (l-phenylalanine)2 using chiral ligand mobile phase was investigated and eight mandelic acid derivatives were enantioseparated by chiral ligand exchange chromatography. The relationship between retention factor and concentration of the Cu(2+) (l-phenylalanine)2 complex was proven to be in conformity with chromatographic retention mechanism in which chiral discrimination occurred both in mobile and stationary phase. Different copper(II) salts, chiral ligands, organic modifier, pH of aqueous phase, and conventional temperature on retention behavior were optimized. Eight racemates were successfully enantioseparated on a common reversed-phase column with an optimized mobile phase composed of 6 mmol/L of l-phenylalanine or N,N-dimethyl-l-phenylalanine and 3 mmol/Lof copper(II) acetate or copper(II) sulfate aqueous solution and methanol.


Assuntos
Cromatografia Líquida de Alta Pressão , Ácidos Mandélicos/análise , Aminoácidos/química , Cobre/química , Sulfato de Cobre/química , Concentração de Íons de Hidrogênio , Ligantes , Metanol/química , Compostos Organometálicos/química , Fenilalanina/análogos & derivados , Fenilalanina/análise , Fenilalanina/química , Estereoisomerismo , Temperatura
13.
J Chromatogr A ; 1360: 110-8, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25087742

RESUMO

This work concentrates on the separation mechanism and application of chiral ligand exchange high-speed countercurrent chromatography in enantioseparation of ten racemic aromatic α-hydroxyl acids, including mandelic acid, 2-chloromandelic acid, 4-methoxymandelic acid, 4-hydroxymandelic acid, α-methylmandelic acid, 4-hydroxy-3-methoxy-mandelic acid, 3-chloromandelic acid, 4-bromomandelic acid, α-cyclopentylmandelic acid and α-cyclohexylmandelic acid, in which five of the racemates were successfully enantioseparated by analytical apparatus with an optimized solvent system. The two-phase solvent system was composed of butanol-water (1:1, v/v) or hexane-n-butanol-water (0.5:0.5:1, v/v), to which N-n-dodecyl-l-proline was added in the organic phase as chiral ligand and cupric acetate was added in the aqueous phase as a transition metal ion. Various influence factors in high-speed countercurrent chromatography were optimized by enantioselective liquid-liquid extraction. The separation mechanism for chiral ligand exchange high-speed countercurrent chromatography was proposed based on the results of present studies. Successful enantioseparations of 72mg of mandelic acid, 76mg of 2-chloromandelic acid and 74mg of 4-methoxymandelic acid were achieved individually with high resolution by preparative high-speed countercurrent chromatography. The HPLC purity of all enantiomers was over 96% with the recovery in the range of 82-90% from the collected fractions.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácidos Mandélicos/isolamento & purificação , Distribuição Contracorrente/métodos , Extração Líquido-Líquido , Ácidos Mandélicos/química , Solventes/química , Estereoisomerismo
14.
J Chromatogr A ; 1218(33): 5602-8, 2011 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21752382

RESUMO

High speed counter-current chromatography (HSCCC) was successfully applied to resolution of phenylsuccinic acid (PSA) with hydroxypropyl-ß-cyclodextrin (HP-ß-CD) as chiral selector (CS). The two-phase solvent system composed of n-hexane-methyl tert-butyl ether-0.1 mol L⁻¹ phosphate buffer solution with pH=2.51 (0.5:1.5:2, v/v/v) was selected. Influence factors involved in the chiral separation were investigated, including the concentration of chiral selector, pH value of the aqueous phase, the separation temperature, and the thermodynamic parameters of inclusion complex were calculated. The complex formation constants were determined using analytical instrument. Two HSCCC elution modes were studied and peak resolution equation was discussed. Under optimum separation conditions, 712 mg of PSA racemate was separated using preparative apparatus. The purities of both of the fractions including (+)-PSA and (-)-PSA from the preparative CCC separation were over 98.5% determined by HPLC and enantiomeric excess of (+)-PSA and (-)-PSA reached 97.6% and 98.6%, respectively. Recovery for the target compounds from the CCC fractions reached 80-82% yielding 285 mg of (+)-PSA and 292 mg of (-)-PSA.


Assuntos
Distribuição Contracorrente/métodos , Succinatos/química , Succinatos/isolamento & purificação , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Adsorção , Distribuição Contracorrente/instrumentação , Estereoisomerismo
15.
J Chromatogr A ; 1070(1-2): 207-10, 2005 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-15861806

RESUMO

High-speed counter-current chromatography (HSCCC) was applied to isolate and purify bioactive compounds in the essential oil of the rhizomes of Curcuma wenyujin. Two sesquiterpenes germacrone and curdione were successfully isolated and purified using two-phase solvent system composed of petroleum ether-ethanol-diethyl ether-water (5/4/0.5/1, v/v) in tail to head elution mode. 62 mg of germacrone and 93 mg of curdione were obtained from 658 mg of the essential oil each at over 95% purity. Their structures were identified by 1H NMR and EI MS.


Assuntos
Distribuição Contracorrente/métodos , Óleos Voláteis/química , Sesquiterpenos de Germacrano/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
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