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Xu Z, Li K, Pan T, Liu J, Li B, Li C, Wang S, Diao Y, Liu X. Lonicerin, an anti-algE flavonoid against Pseudomonas aeruginosa virulence screened from Shuanghuanglian formula by molecule docking based strategy. JOURNAL OF ETHNOPHARMACOLOGY 2019; 239:111909. [PMID: 31026553 DOI: 10.1016/j.jep.2019.111909] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 04/18/2019] [Accepted: 04/23/2019] [Indexed: 05/22/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The Shuanghuanglian formula (SF) is a famous antimicrobial and antiviral traditional Chinese medicine that is made of Lonicera japonica Thunb., Scutellaria baicalensis Georgi, and Forsythia suspensa (Thunb.) Vahl. According to the Chinese Pharmacopoeia, the SF is commonly administered in the forms of oral liquid, tablets, and injection. It has long been used to treat acute respiratory tract infections, especially lung infection. AIM OF THE STUDY In the light of the increasing incidence of multidrug resistance to conventional antibiotics, the aim of this study was to screen potential anti-virulence agents against Pseudomonas aeruginosa from the extract of the SF. MATERIALS AND METHODS The SF was used for effective compounds screening via the combination of the molecule docking approach and ultra-high-performance liquid chromatography-quadrupole/time of flight mass spectrometry. Fifty-one anti-virulence-related proteins were docked, 26 identified compounds were from SF. Subsequently, the top-scoring screened compound was assessed via bioactive-related assays, including the quantification of alginate biosynthesis, anti-biofilm assays, and the A549 human lung cells infection. RESULT A flavonoid Lonicerin was found to be bonded with the active site of the alginate secretion protein (AlgE) with the highest score in molecule docking. Furthermore, we validated that Lonicerin could significantly reduce alginate secretion (25 μg/mL) and biofilm formation (12.5 μg/mL) at a sub-MIC concentration without inhibiting the proliferation of P. aeruginosa or influencing the expression of AlgE, which suggested that Lonicerin may directly inhibit AlgE. In addition, Lonicerin was proven to inhibit the infection of P. aeruginosa in the A549 cells. CONCLUSION This work reported on the first potential AlgE antagonist that was derived from herbal resources. Lonicerin was proven to be an effective inhibitor in-vitro of P. aeruginosa infection.
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Affiliation(s)
- Zhongren Xu
- College of Pharmacy, Dalian Medical University, Dalian, PR China
| | - Kun Li
- College of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian, PR China
| | - Taowen Pan
- Institute of Integrative Medicine, Dalian Medical University, Dalian, PR China
| | - Jing Liu
- College of Pharmacy, Dalian Medical University, Dalian, PR China
| | - Bin Li
- College of Pharmacy, Dalian Medical University, Dalian, PR China
| | - Chuanxun Li
- College of Pharmacy, Dalian Medical University, Dalian, PR China
| | - Shouyu Wang
- The First Affiliated Hospital of Dalian Medical University, Dalian, PR China
| | - Yunpeng Diao
- College of Pharmacy, Dalian Medical University, Dalian, PR China.
| | - Xinguang Liu
- Institute of Integrative Medicine, Dalian Medical University, Dalian, PR China.
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Friesen JB, McAlpine JB, Chen SN, Pauli GF. Countercurrent Separation of Natural Products: An Update. JOURNAL OF NATURAL PRODUCTS 2015; 78:1765-96. [PMID: 26177360 PMCID: PMC4517501 DOI: 10.1021/np501065h] [Citation(s) in RCA: 196] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Indexed: 05/02/2023]
Abstract
This work assesses the current instrumentation, method development, and applications in countercurrent chromatography (CCC) and centrifugal partition chromatography (CPC), collectively referred to as countercurrent separation (CCS). The article provides a critical review of the CCS literature from 2007 since our last review (J. Nat. Prod. 2008, 71, 1489-1508), with a special emphasis on the applications of CCS in natural products research. The current state of CCS is reviewed in regard to three continuing topics (instrumentation, solvent system development, theory) and three new topics (optimization of parameters, workflow, bioactivity applications). The goals of this review are to deliver the necessary background with references for an up-to-date perspective of CCS, to point out its potential for the natural product scientist, and thereby to induce new applications in natural product chemistry, metabolome, and drug discovery research involving organisms from terrestrial and marine sources.
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Affiliation(s)
- J. Brent Friesen
- Department
of Medicinal Chemistry and Pharmacognosy and Institute for Tuberculosis Research,
College of Pharmacy, University of Illinois
at Chicago, Chicago, Illinois 60612, United
States
- Physical
Sciences Department, Rosary College of Arts and Sciences, Dominican University, River Forest, Illinois 60305, United States
| | - James B. McAlpine
- Department
of Medicinal Chemistry and Pharmacognosy and Institute for Tuberculosis Research,
College of Pharmacy, University of Illinois
at Chicago, Chicago, Illinois 60612, United
States
| | - Shao-Nong Chen
- Department
of Medicinal Chemistry and Pharmacognosy and Institute for Tuberculosis Research,
College of Pharmacy, University of Illinois
at Chicago, Chicago, Illinois 60612, United
States
| | - Guido F. Pauli
- Department
of Medicinal Chemistry and Pharmacognosy and Institute for Tuberculosis Research,
College of Pharmacy, University of Illinois
at Chicago, Chicago, Illinois 60612, United
States
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Developments of instruments and methods related with high-speed countercurrent chromatography and their applications in research of natural medicines. OPEN CHEM 2012. [DOI: 10.2478/s11532-011-0141-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractHigh-speed countercurrent chromatography (HSCCC) is a liquid-liquid separation chromatographic technique which uses no solid supporting medium. During its rapid development in the last 30 years, great progress has been made in the instrumentation, the basic study and application of HSCCC. It has significant advantages over other instrumental separation techniques, in its high efficiency and continuous processing capability. In recent years, HSCCC has been widely used in research and development of natural medicines and functional foods, including preparative separation, fingerprint analysis and screening of bioactive constituents. A review of the technique is presented in this paper.
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Simkhada D, Lee HC, Sohng JK. Genetic engineering approach for the production of rhamnosyl and allosyl flavonoids from Escherichia coli. Biotechnol Bioeng 2010; 107:154-62. [PMID: 20506539 DOI: 10.1002/bit.22782] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The main functions of glycosylation are stabilization, detoxification and solubilization of substrates and products. To produce glycosylated products, Escherichia coli was engineered by overexpression of TDP-L-rhamnose and TDP-6-deoxy-D-allose biosynthetic gene clusters, and flavonoids were glycosylated by the overexpression of the glycosyltransferase gene from Arabidopsis thaliana. For the glycosylation, these flavonoids (quercetin and kaempferol) were exogenously fed to the host in a biotransformation system. The products were isolated, analyzed and confirmed by HPLC, LC/MS, and ESI-MS/MS analyses. Several conditions (arabinose, IPTG concentration, OD(600), substrate concentration, incubation time) were optimized to increase the production level. We successfully isolated approximately 24 mg/L 3-O-rhamnosyl quercetin and 12.9 mg/L 3-O-rhamnosyl kaempferol upon feeding of 0.2 mM of the respective flavonoids and were also able to isolate 3-O-allosyl quercetin. Thus, this study reveals a method that might be useful for the biosynthesis of rhamnosyl and allosyl flavonoids and for the glycosylation of related compounds.
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Affiliation(s)
- Dinesh Simkhada
- Institute of Biomolecule Reconstruction, Department of Pharmaceutical Engineering, Sun Moon University, Tangjeong-myeon, Asansi, Chungnam, Korea
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Costa FDN, Leitão GG. Strategies of solvent system selection for the isolation of flavonoids by countercurrent chromatography. J Sep Sci 2010; 33:336-47. [PMID: 20169552 DOI: 10.1002/jssc.200900632] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Flavonoids form a large class of important naturally occurring bioactive compounds. Their isolation and purification from natural sources can sometimes be very difficult and time-consuming when traditional phytochemical techniques are used. Countercurrent chromatography (CCC), a support-free liquid-liquid partition chromatography technique, is very useful for the isolation of polar compounds and its use is increasing in the natural products field. In this paper, we propose strategies of solvent system selection for the isolation of flavonoids by CCC, based on data from the literature, plus incorporation of own practical experiences. The selected references report the isolation of over 300 different flavonoid compounds from more than 100 plant species, using 40 different solvent systems, showing the versatility of this technique. The solvent system hexane-ethylacetate-methanol-water is proposed as a starting point for the separation of samples containing free flavonoids, as it was cited in more than 60% of the papers. A "fine tuning" step is proposed at each level of this solvent family. Other modifications include exchanging the alcohol in the system as well as introducing a fifth solvent. The solvent system ethyl-acetate-butanol-water is proposed as the starting point for glycosylated flavonoids. Other solvent systems are also discussed. The use of gradients is proposed for samples containing both free and glycosylated flavonoids, as the polarity window is larger in these cases. High-speed countercurrent chromatography was used in 89% of the reviewed data.
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Affiliation(s)
- Fernanda das Neves Costa
- Universidade Federal do Rio de Janeiro, Núcleo de Pesquisas de Produtos Naturais, Rio de Janeiro, Brazil
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Target-guided separation of Bougainvillea glabra betacyanins by direct coupling of preparative ion-pair high-speed countercurrent chromatography and electrospray ionization mass-spectrometry. J Chromatogr A 2010; 1217:4544-54. [PMID: 20494364 DOI: 10.1016/j.chroma.2010.04.061] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Revised: 04/14/2010] [Accepted: 04/21/2010] [Indexed: 11/23/2022]
Abstract
In this study, preparative ion-pair high-speed countercurrent chromatography was directly coupled to an electrospray ionization mass-spectrometry device (IP-HSCCC/ESI-MS-MS) for target-guided fractionation of high molecular weight acyl-oligosaccharide linked betacyanins from purple bracts of Bougainvillea glabra (Nyctaginaceae). The direct identification of six principal acyl-oligosaccharide linked betacyanins in the mass range between m/z 859 and m/z 1359 was achieved by positive ESI-MS ionization and gave access to the genuine pigment profile already during the proceeding of the preparative separation. Inclusively, all MS/MS-fragmentation data were provided during the chromatographic run for a complete analysis of substitution pattern. On-line purity evaluation of the recovered fractions is of high value in target-guided screening procedures and for immediate decisions about suitable fractions used for further structural analysis. The applied preparative hyphenation was shown to be a versatile screening method for on-line monitoring of countercurrent chromatographic separations of polar crude pigment extracts and also traced some minor concentrated compounds. For the separation of 760mg crude pigment extract the biphasic solvent system tert.-butylmethylether/n-butanol/acetonitrile/water 2:2:1:5 (v/v/v/v) was used with addition of ion-pair forming reagent trifluoroacetic acid. The preparative HSCCC-eluate had to be modified by post-column addition of a make-up solvent stream containing formic acid to reduce ion-suppression caused by trifluoroacetic acid and later significantly maximized response of ESI-MS/MS detection of target substances. A variable low-pressure split-unit guided a micro-eluate to the ESI-MS-interface for sensitive and direct on-line detection, and the major volume of the effluent stream was directed to the fraction collector for preparative sample recovery. The applied make-up solvent mixture significantly improved smoothness of the continuously measured IP-HSCCC-ESI-MS base peak ion trace in the experimental range of m/z 50-2200 by masking stationary phase bleeding and generating a stable single solvent phase for ESI-MS/MS detection. Immediate structural data were retrieved throughout the countercurrent chromatography run containing complete MS/MS-fragmentation pattern of the separated acyl-substituted betanidin oligoglycosides. Single ion monitoring indicated clearly the base-line separation of higher concentrated acylated betacyanin components.
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Recent Progress of High-speed Counter-current Chromatography Coupling with Other Relative Technologies in Natural Product. Chin J Nat Med 2010. [DOI: 10.3724/sp.j.1009.2010.00062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Simkhada D, Kim E, Lee HC, Sohng JK. Metabolic engineering of Escherichia coli for the biological synthesis of 7-O-xylosyl naringenin. Mol Cells 2009; 28:397-401. [PMID: 19812897 DOI: 10.1007/s10059-009-0135-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Accepted: 08/26/2009] [Indexed: 10/20/2022] Open
Abstract
Flavonoids are a group of polyphenolic compounds that have been recognized as important due to their physiological and pharmacological roles and their health benefits. Glycosylation of flavonoids has a wide range of effects on flavonoid solubility, stability, and bioavailability. We previously generated the E. coli BL21 (DE3) Deltapgi host by deleting the glucose-phosphate isomerase (Pgi) gene in E. coli BL21 (DE3). This host was further engineered for whole-cell biotransformation by integration of galU from E. coli K12, and expression of calS8 (UDP-glucose dehydrogenase) and calS9 (UDP-glucuronic acid decarboxylase) from Micromonospora echinospora spp. calichensis and arGt-4 (7-O-glycosyltransferase) from Arabidopsis thaliana to form E. coli (US89Gt-4), which is expected to produce glycosylated flavonoids. To test the designed system, the engineered host was fed with naringenin as a substrate, and naringenin 7-O-xyloside, a glycosylated naringenin product, was detected. Product was verified by HPLCLC/MS and ESI-MS/MS analyses. The reconstructed host can be applied for the production of various classes of glycosylated flavonoids.
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Affiliation(s)
- Dinesh Simkhada
- Department of Pharmaceutical, Institute of Biomolecule Reconstruction, Sun Moon University, Asan 336-708, Korea
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Abstract
Countercurrent chromatography (CCC) is a generic term covering all forms of liquid-liquid chromatography that use a support-free liquid stationary phase held in place by a simple centrifugal or complex centrifugal force field. Biphasic liquid systems are used with one liquid phase being the stationary phase and the other being the mobile phase. Although initiated almost 30 years ago, CCC lacked reliable columns. This is changing now, and the newly designed centrifuges appearing on the market make excellent CCC columns. This review focuses on the advantages of a liquid stationary phase and addresses the chromatographic theory of CCC. The main difference with classical liquid chromatography (LC) is the variable volume of the stationary phase. There are mainly two different ways to obtain a liquid stationary phase using centrifugal forces, the hydrostatic way and the hydrodynamic way. These two kinds of CCC columns are described and compared. The reported applications of CCC in analytical chemistry and comparison with other separation and enrichment methods show that the technique can be successfully used in the analysis of plants and other natural products, for the separation of biochemicals and pharmaceuticals, for the separation of alkaloids from medical herbs, in food analysis, etc. On the basis of the studies of the last two decades, recommendations are also given for the application of CCC in trace inorganic analysis and in radioanalytical chemistry.
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Role of counter-current chromatography in the modernisation of Chinese herbal medicines. J Chromatogr A 2009; 1216:740-53. [DOI: 10.1016/j.chroma.2008.11.095] [Citation(s) in RCA: 163] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Revised: 11/17/2008] [Accepted: 11/20/2008] [Indexed: 11/20/2022]
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Berthod A, Ruiz-Angel MJ, Carda-Broch S. Countercurrent chromatography: people and applications. J Chromatogr A 2008; 1216:4206-17. [PMID: 18986655 DOI: 10.1016/j.chroma.2008.10.071] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 10/02/2008] [Accepted: 10/08/2008] [Indexed: 11/18/2022]
Abstract
The scientific literature was scanned for the published research articles dealing with countercurrent chromatography (CCC) over the time period 1980-May 2008. The search returned 1638 articles that were analyzed focussing on people and applications. Concerning the people, it was found that the geographical location of the CCC authors was relatively well balanced between USA, Asia with mainly China and Japan and Europe. Yoichiro Ito, the inventor of the technique, is by far the most productive author in the field with 331 articles or more than one over five CCC articles published in the time period. Without surprise, English is the dominant language with more than 82% of the articles. A significant 8% amount of CCC articles were published in Chinese in Chinese journals. Chromatography journals are the logical tribune for half of the published CCC articles. Concerning the applications, the separation and purification of natural compounds is the dominant theme in CCC making the subject of more than one article over two. Starting from the plant extract, CCC in few steps can produce significant amounts of more than 95% pure compounds used for identification and/or property studies. Other applications are found in the pharmaceutical and chemical field. The separation of enantiomers on the preparative scale is a field of growing importance.
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Affiliation(s)
- A Berthod
- Université de Lyon, CNRS UMR, Villeurbanne, France.
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Pauli GF, Pro SM, Friesen JB. Countercurrent separation of natural products. JOURNAL OF NATURAL PRODUCTS 2008; 71:1489-508. [PMID: 18666799 DOI: 10.1021/np800144q] [Citation(s) in RCA: 154] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
An assessment of the technology and method development in countercurrent chromatography (CCC) and centrifugal partition chromatography (CPC), collectively referred to as countercurrent separation (CS), is provided. More than six decades of CS theory and applications are critically reviewed and developed into a practical guide to CS for natural products research. The necessary theoretical foundation is given for better use of CS in the separation of biological molecules of any size, small to large, and from any matrix, simple to complex. The three operational fundamentals of CS--instrumentation, biphasic solvent systems, and theory--are covered in a prismatic fashion. The goal of this review is to provide the necessary background and references for an up-to-date perspective of CS and to point out its potential for the natural products scientist for applications in natural products chemistry, metabolome, and proteome research involving organisms from terrestrial and marine sources.
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Affiliation(s)
- Guido F Pauli
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois 60612, USA.
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Tsimogiannis D, Samiotaki M, Panayotou G, Oreopoulou V. Characterization of flavonoid subgroups and hydroxy substitution by HPLC-MS/MS. Molecules 2007; 12:593-606. [PMID: 17851414 PMCID: PMC6149353 DOI: 10.3390/12030593] [Citation(s) in RCA: 190] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2007] [Revised: 03/13/2007] [Accepted: 03/14/2007] [Indexed: 11/16/2022] Open
Abstract
HPLC-DAD coupled with mass spectrometry in the positive ionization mode was applied to study the fragmentation of twelve selected flavonoids. Compounds belonging to all the major subgroups found in common plants, i.e. flavonols, flavones, dihydroflavonols, flavanones and flavanols were studied. Compound standards were injected into the spectrometer and produced characteristic mass spectra. The fragmentation of each compound was studied and it was shown that the dehydration and carbon monoxide losses from the [M+H]+ ion by the members of each subgroup produced specific fragments, thus allowing the characterization of the flavonoid subgroups. Moreover, fragments resulting from fission of the C-rings are specific of each subgroup and revealed the substitution pattern of A- and B-rings. In order to verify the identifying efficiency of the positive ionization mode through these characteristic fragmentations, the unknown flavonoids of an Origanum vulgare diethyl ether extract were separated with the HPLC system and the major peaks were successfully identified with the mass spectrometer.
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Affiliation(s)
- Dimitrios Tsimogiannis
- National Technical University of Athens, School of Chemical Engineering, 9 Iroon Polytehniou st, Zografou Campus, 157 80, Athens, Greece; Tel: +302107723166, Fax: +302107723163
- Authors to whom correspondence should be addressed; E-mail: ;
| | - Martina Samiotaki
- Biomedical Sciences Research Center “Alexander Fleming”, 34 Fleming st, 16672, Vari, Greece
| | - George Panayotou
- Biomedical Sciences Research Center “Alexander Fleming”, 34 Fleming st, 16672, Vari, Greece
| | - Vassiliki Oreopoulou
- National Technical University of Athens, School of Chemical Engineering, 9 Iroon Polytehniou st, Zografou Campus, 157 80, Athens, Greece; Tel: +302107723166, Fax: +302107723163
- Authors to whom correspondence should be addressed; E-mail: ;
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Chen LJ, Song H, Du QZ, Li J, Ito Y. Analysis of Flavonoids in the Extracts from the Seeds of Oroxylum indicum Using High Speed Countercurrent Chromatography/Mass Spectrometry. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-200058350] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- L. J. Chen
- a Center for Biotherapy of Cancer and Cancer Center , First University Hospital, West China University of Medical Sciences, Huaxi Medical School, Sichuan University , P.R. China
| | - H. Song
- b Department of Pharmaceutical and Bioengineering , Sichuan University , P.R. China
| | - Q. Z. Du
- c Institute of Food and Biological Engineering , Zhejiang Gongshang University , Hangzhou, P.R. China
| | - Jianrong Li
- c Institute of Food and Biological Engineering , Zhejiang Gongshang University , Hangzhou, P.R. China
| | - Y. Ito
- d Center of Biochemistry and Biophysics , National Heart, Lung, and Blood Institute, National Institutes of Health , Bethesda, MD, USA
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Chen LJ, Song H, Games DE, Sutherland IA. HSCCC‐MS Study of Flavonoids in the Extracts from the Seeds of Oroxylum indicum. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-200063651] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- L. J. Chen
- a State Key Laboratory of Biotherapy and Cancer Center , West China Hospital, West China Medical School, Sichuan University , P.R. China
| | - H. Song
- b Department of Pharmaceutical and Bioengineering , Sichuan University , P.R. China
| | - D. E. Games
- c Mass Spectrometry Research Unit , University of Wales Swansea
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Brent Friesen J, Pauli GF. G.U.E.S.S.—A Generally Useful Estimate of Solvent Systems for CCC. J LIQ CHROMATOGR R T 2007. [DOI: 10.1080/10826070500225234] [Citation(s) in RCA: 165] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- J. Brent Friesen
- a Department of Natural Science , Rosary College of Arts and Sciences, Dominican University , River Forest, Illinois, USA
| | - Guido F. Pauli
- b Department of Medicinal Chemistry, and Pharmacognosy , Institute for Tuberculosis Research, College of Pharmacy, University of Illinois at Chicago , Chicago, Illinois, USA
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Guimarães Leitão G, Santos El‐Adji S, de Melo WAL, Guimarães Leitão S, Brown L. Separation of Free and Glycosylated Flavonoids from Siparuna guianensis by Gradient and Isocratic CCC. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-200063669] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Gilda Guimarães Leitão
- a Núcleo de Pesquisas de Produtos Naturais , Universidade Federal do Rio de Janeiro , Rio de Janeiro, RJ, Brazil
| | - Samira Santos El‐Adji
- a Núcleo de Pesquisas de Produtos Naturais , Universidade Federal do Rio de Janeiro , Rio de Janeiro, RJ, Brazil
| | - Walédya Araújo Lopes de Melo
- a Núcleo de Pesquisas de Produtos Naturais , Universidade Federal do Rio de Janeiro , Rio de Janeiro, RJ, Brazil
| | - Suzana Guimarães Leitão
- b Departamento de Produtos Naturais e Alimentos , Faculdade de Farmácia, UFRJ , Rio de Janeiro, RJ, Brazil
| | - Les Brown
- c AECS , Mid Glamorgan, South Wales, UK
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Current awareness in phytochemical analysis. PHYTOCHEMICAL ANALYSIS : PCA 2003; 14:389-396. [PMID: 14667067 DOI: 10.1002/pca.681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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