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Peter Winterhalter - One of the best experts on this subject based on the ideXlab platform.
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The 10th international conference on Countercurrent Chromatography held at Technische Universität Braunschweig, Braunschweig, Germany, August 1-3, 2018.
Journal of chromatography. A, 2019Co-Authors: Gerold Jerz, Peter WinterhalterAbstract:Abstract The 10th International Countercurrent Chromatography Conference (CCC 2018) was held at Technische Universitat Braunschweig, Germany, from August 1st–3rd, 2018. The presentations in the scientific program demonstrated the progress in the field of Countercurrent Chromatography (CCC) and centrifugal partition Chromatography (CPC) in recent years and numerous applications have impressively proven the potential of this all-liquid separation technique not only for academic research but also for industry. Special highlights of the conference were the celebration of the 90th birthday of Dr. Yoichiro Ito, the pioneer of Countercurrent Chromatography, as well as the foundation of an international “Society of Partition and Countercurrent Chromatography (SPCC)”
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Fractionation of four Colombian essential oils by Countercurrent Chromatography and evaluation of their antioxidant activity
Journal of Essential Oil Research, 2019Co-Authors: Beatriz E. Jaramillo-colorado, Elena E. Stashenko, Peter WinterhalterAbstract:ABSTRACTHigh-speed Countercurrent Chromatography (HSCCC) is widely used for isolation of biologically active compounds of plant extracts and essential oils (EOs) in preparative scale. The objective...
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isolation of dimeric trimeric tetrameric and pentameric procyanidins from unroasted cocoa beans theobroma cacao l using Countercurrent Chromatography
Food Chemistry, 2015Co-Authors: Tuba Esatbeyoglu, Victor Wray, Peter WinterhalterAbstract:Abstract The main procyanidins, including dimeric B2 and B5, trimeric C1, tetrameric and pentameric procyanidins, were isolated from unroasted cocoa beans ( Theobroma cacao L.) using various techniques of Countercurrent Chromatography, such as high-speed Countercurrent Chromatography (HSCCC), low-speed rotary Countercurrent Chromatography (LSRCCC) and spiral-coil LSRCCC. Furthermore, dimeric procyanidins B1 and B7, which are not present naturally in the analysed cocoa beans, were obtained after semisynthesis of cocoa bean polymers with (+)-catechin as nucleophile and separated by Countercurrent Chromatography. In this way, the isolation of dimeric procyanidin B1 in considerable amounts (500 mg, purity > 97%) was possible in a single run. This is the first report concerning the isolation and semisynthesis of dimeric to pentameric procyanidins from T. cacao by Countercurrent Chromatography. Additionally, the chemical structures of tetrameric (cinnamtannin A2) and pentameric procyanidins (cinnamtannin A3) were elucidated on the basis of 1 H NMR spectroscopy. Interflavanoid linkage was determined by NOE-correlations, for the first time.
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ASEV Honorary Research Lecture 2008: Application of Countercurrent Chromatography for Wine Research and Wine Analysis
American Journal of Enology and Viticulture, 2009Co-Authors: Peter WinterhalterAbstract:One of the few liquid chromatographic techniques that can be predictably scaled up from analytical to process scale is Countercurrent Chromatography (CCC). Countercurrent Chromatography furthermore enables a 100% recovery of the sample and, because of its gentle separation conditions, is ideally suited to the analysis of various groups of wine constituents. In this review, CCC instrumentation and its application to the analysis of labile wine aroma precursors, antioxidants, and pigments are examined. Moreover, novel centrifugal precipitation Chromatography instrumentation for the fractionation of polymeric wine constituents and the scale-up of the technique for separations in the 10 to 100 g range are described.
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Application of Countercurrent Chromatography for wine research and wine analysis.
American Journal of Enology and Viticulture, 2009Co-Authors: Peter WinterhalterAbstract:t: One of the few liquid chromatographic techniques that can be predictably scaled up from analytical to process scale is Countercurrent Chromatography (CCC). Countercurrent Chromatography furthermore enables a 100% recovery of the sample and, because of its gentle separation conditions, is ideally suited to the analysis of various groups of wine constituents. In this review, CCC instrumentation and its application to the analysis of labile wine aroma precursors, antioxidants, and pigments are examined. Moreover, novel centrifugal precipitation Chromatography instrumentation for the fractionation of polymeric wine constituents and the scale-up of the technique for separations in the 10 to 100 g range are described.
Sheng-qiang Tong - One of the best experts on this subject based on the ideXlab platform.
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Enantioseparation of 2-(4-chlorophenyl)succinic acid by Countercurrent Chromatography and investigation of injection volume on resolution.
Journal of separation science, 2020Co-Authors: Yang Jin, Wenyu Sun, Honglei Bao, Hengmian Sun, Shanshan Zhao, Xiang Wang, Sheng-qiang TongAbstract:2-(4-chlorophenyl) succinic acid was successfully enantioseparated by Countercurrent Chromatography using hydroxypropyl-β-cyclodextrin as chiral selector. A two-phase solvent system composed of n-hexane-ethyl acetate-0.1 mol/L phosphate buffer with pH 2.65 (5:5:10, v/v/v) was selected. Enantioselective liquid-liquid extraction was used to optimize the enantioseparation conditions. Meanwhile, the influence of injection volume on resolution in Countercurrent Chromatography was investigated and a linear relationship between the inflection point of injection volume and sample loading was tentatively obtained. The peak resolution will decrease significantly when the injection volume over the inflection point was used. In addition, it could be found that the smaller amount of sample loading, the larger impact of injection volume on resolution could be observed, which might serve as a good reference for the selection of sample volume in enantioseparations by Countercurrent Chromatography. Under optimized conditions, 20 mg of 2-(4-chlorophenyl) succinic acid racemate dissolved in 10 mL of aqueous phase was successfully enantioseparated by Countercurrent Chromatography. The recovery for both of the enantiomer of (±)-2-(4-chlorophenyl) succinic acid reached more than 70%-75% with a purity of 99.0%. This article is protected by copyright. All rights reserved.
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Chiral Separations by Countercurrent Chromatography.
Methods in molecular biology (Clifton N.J.), 2019Co-Authors: Sheng-qiang TongAbstract:Chiral separations by Countercurrent Chromatography are mainly divided into two types: homogeneous chiral selector addition and interfacial chiral ligand exchange. In this chapter, we describe two methods for the enantioseparation of phenylsuccinic acid and α-hydroxy acids by high-speed Countercurrent Chromatography using hydroxypropyl-β-cyclodextrin and N-n-dodecyl-L-proline as chiral selectors for both above mentioned modes.
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Separation and purification of intermediates for the preparation of naproxen from synthetic mixtures by Countercurrent Chromatography.
Journal of separation science, 2018Co-Authors: Xujun Qiu, Wenyu Sun, Chaoyue Wang, Jizhong Yan, Sheng-qiang TongAbstract:Three key intermediates in the preparation of the nonsteroidal anti-inflammatory drug naproxen were successfully separated and purified with high purity from synthetic mixtures by Countercurrent Chromatography with a selected biphasic solvent system. The biphasic solvent system composed of n-hexane/ethyl acetate/methanol/water (9:1:9:1, v/v/v/v) was selected according to partition performance of the three components using thin-layer Chromatography. Fifty milligrams of the synthetic mixture after the three-step reaction was injected into a preparative Countercurrent Chromatography separation column and yielded 3.5, 14.0, and 8.0 mg of three key intermediates with 95.0, 99.0, and 98.0% purity, and the recovery of each component was 65.2, 71.2, and 69.6%, respectively. The results indicated that Countercurrent Chromatography is an efficient alternative and economical method for the separation and purification of intermediate components from synthetic mixtures.
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Chiral ligand exchange Countercurrent Chromatography: Enantioseparation of amino acids.
Journal of separation science, 2018Co-Authors: Qing Xiong, Jing Jin, Sheng-qiang TongAbstract:This work deals with the enantioseparation of α-amino acids by chiral ligand exchange high-speed Countercurrent Chromatography using N-n-dodecyl-l-hydroxyproline as a chiral ligand and copper(II) as a transition metal ion. A biphasic solvent system composed of n-hexane/n-butanol/aqueous phase with different volume ratios was selected for each α-amino acid. The enantioseparation conditions were optimized by enantioselective liquid-liquid extractions, in which the main influence factors, including type of chiral ligand, concentration of chiral ligand and transition metal ion, separation temperature, and pH of the aqueous phase, were investigated for racemic phenylalanine. Altogether, we tried to enantioseparate 15 racemic α-amino acids by the analytical Countercurrent Chromatography, of which only five of them could be successfully enantioseparated. Different elution sequence for phenylalanine enantiomer was observed compared with traditional liquid Chromatography and the proposed interactions between chiral ligand, transition metal ion (Cu2+ ), and enantiomer are discussed.
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pH-zone-refining elution-extrusion Countercurrent Chromatography: Separation of hydroxyanthraquinones from Cassiae semen.
Journal of separation science, 2017Co-Authors: Chu Chu, Sheng-qiang TongAbstract:Seven hydroxyanthraquinones were successfully separated from the traditional Chinese medicinal herb Cassiae Semen by conventional and pH-zone-refining Countercurrent Chromatography with an environmentally friendly biphasic solvent system, in which elution–extrusion mode was investigated for pH-zone-refining Countercurrent Chromatography for the first time. A two-phase solvent system composed of n-hexane/ethyl acetate/ethanol/water (5:3:4:4, v/v) was used for the conventional Countercurrent Chromatography while the same system with a different volume ratio n-hexane/ethyl acetate/ethanol/water (3:5:2:6, v/v) was used for pH-zone-refining Countercurrent Chromatography, in which 20 mmol L−1 of trifluoroacetic acid was added in the organic phase as a retainer and 15 mmol L−1 of ammonia was added to the aqueous phase as an eluter. A 400 mg crude sample could be well separated by pH-zone-refining Countercurrent Chromatography, yielding 53 mg of aurantio-obtusin, 40 mg of chryso-obtusin, 18 mg of obtusin, 24 mg of obtusifolin, 10 mg of emodin and 105 mg the mixture of chrysophanol and physcion with a purity of over 95.8, 95.7, 96.9, 93.5, 97.4, 77.1 and 19.8%, as determined by high-performance liquid Chromatography. Furthermore, the difference in elution sequence between conventional and pH-zone-refining mode was observed and discussed. This article is protected by copyright. All rights reserved
Li-ming Yuan - One of the best experts on this subject based on the ideXlab platform.
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Progress of chiral Countercurrent Chromatography
Se pu = Chinese journal of chromatography, 2016Co-Authors: Li-ming YuanAbstract:This article summarizes five characteristics of chiral Countercurrent Chromatography (CCC). The progress of chiral Countercurrent Chromatography is introduced. In the high speed Countercurrent Chromatography, the chiral selectors such as amino acid derivatives, cyclodextrin derivatives, chiral organic acid, polysaccharide and bovine serum albumin (BSA) are reviewed.
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Preparative Purification of Single Walled Carbon Nanotubes by High Speed Countercurrent Chromatography
Journal of Liquid Chromatography & Related Technologies, 2008Co-Authors: Y. Cai, Zhi-hong Yan, Li-ming YuanAbstract:Abstract The application of high speed Countercurrent Chromatography to the preparative purification of crude single walled carbon nanotubes is described. The purification was accomplished on the basis of an experiment that dispersed the single walled carbon nanotubes with aniline, the result mixture was separated by high speed Countercurrent Chromatography using the two phase system composed of chloroform/methanol/water = 4/4/2. The sizes of SWNTs separated were observed by scanning electron microscopy. The experimental results demonstrated that the high speed Countercurrent Chromatography possessed good efficiency for purification of single walled carbon nanotubes.
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High-speed Countercurrent Chromatography for purification of single-walled carbon nanotubes
Chinese Chemical Letters, 2008Co-Authors: Y. Cai, Zhi-hong Yan, Li-ming YuanAbstract:Abstract A new chromatographic purification of single-walled carbon nanotubes using high-speed Countercurrent Chromatography is reported. The purification was accomplished on the basis of experiment that dispersed the single-walled carbon nanotubes with sodium dodecyl sulfate, and the result mixture was separated using the two phase system composed of n -butanol/water = 1/1 (v/v). The sizes of SWNTs separated were observed by scanning electron microscopy. The results demonstrated that the high-speed Countercurrent Chromatography possessed a good efficency for purification of single-walled carbon nanotubes.
Yoichiro Ito - One of the best experts on this subject based on the ideXlab platform.
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Isolation of Sutherlandioside B from Sutherlandia frutescens by Spiral Countercurrent Chromatography.
Journal of liquid chromatography & related technologies, 2014Co-Authors: Korey J. Brownstein, Yoichiro Ito, Martha Knight, George E. Rottinghaus, William R. FolkAbstract:The introduction of spiral Countercurrent Chromatography in the last few years using new separation columns such as the spiral tubing support rotor has enabled the application of more polar volatile solvent systems for natural products separation. This method can be applied to water soluble compounds and their metabolites. We have used spiral Countercurrent Chromatography with the spiral tubing support rotor to fractionate n-butanol extracts of an African plant Sutherlandia frutescens and have determined conditions by which the predominant cycloartane glycoside (sutherlandioside B) can be purified in good yield. A solvent system of ethyl acetate, methanol, and water was modified by adding n-butanol to separate sutherlandioside B from other compounds. With the optimal amount of n-butanol in the two-phase solvent system with the lower aqueous phase mobile, the target compound was eluted well separated from the other components. The purity of sutherlandioside B was determined by high performance liquid Chromatography/mass spectrometry analysis and the yield compares favorably with the content in bulk material.
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Recent Progress on Countercurrent Chromatography Modeling
Journal of liquid chromatography & related technologies, 2014Co-Authors: Fengkang Wang, Yoichiro Ito, Yun WeiAbstract:As Countercurrent Chromatography is becoming an established method in Chromatography for many kinds of products, it is becoming increasingly important to model the process and to be able to predict the peaks for a given process. The CCC industries are looking for rapid methods to analyze the processes of Countercurrent Chromatography and select a suitable solvent system. In this paper, recent progress is reviewed in the development and demonstration of several types of models of Countercurrent Chromatography. Literature lists a number of Countercurrent Chromatography (CCC) models that can predict the retention time and, to a certain extent, the peak width of a solute eluting from a CCC column, such as cell model, CCD model, CSTRs model, probabilistic model, temperature dependence plate model, physical models, and so forth.
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Spiral Countercurrent Chromatography.
Journal of chromatographic science, 2013Co-Authors: Yoichiro Ito, Martha Knight, Thomas M. FinnAbstract:For many years, high-speed Countercurrent Chromatography conducted in open tubing coils has been widely used for the separation of natural and synthetic compounds. In this method, the retention of the stationary phase is solely provided by the Archimedean screw effect by rotating the coiled column in the centrifugal force field. However, the system fails to retain enough of the stationary phase for polar solvent systems such as the aqueous–aqueous polymer phase systems. To address this problem, the geometry of the coiled channel was modified to a spiral configuration so that the system could utilize the radially acting centrifugal force. This successfully improved the retention of the stationary phase. Two different types of spiral columns were fabricated: the spiral disk assembly, made by stacking multiple plastic disks with single or four interwoven spiral channels connected in series, and the spiral tube assembly, made by inserting the tetrafluoroethylene tubing into a spiral frame (spiral tube support). The capabilities of these column assemblies were successfully demonstrated by separations of peptides and proteins with polar two-phase solvent systems whose stationary phases had not been well retained in the earlier multilayer coil separation column for high-speed Countercurrent Chromatography.
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Separation of Peptides by Spiral Countercurrent Chromatography
Journal of Liquid Chromatography & Related Technologies, 2008Co-Authors: Martha Knight, Yoichiro Ito, Thomas M. FinnAbstract:Abstract Spiral Countercurrent Chromatography (CCC) utilizes a new separation rotor composed of 8 high density polyethylene plates with spiral flow channels, mounted in the type‐J coil planet centrifuge (CPC). Synthetic peptides were evaluated for partition coefficients in various solvent systems. Approximately 30 mg amounts were chromatographed and the fractions analyzed for peptide content and purity. The solvent systems which contained sec‐butanol or n‐butanol and the mobile phase selected produced good purification. The stationary phase was highly retained over 60%, thus the spiral separation coil is able to retain these more viscous, low interfacial tension solvents that have not been able to be used well in the multi‐layer coil for high speed CCC.
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isolation of hyperoside and luteolin glucoside from agrimonia pilosa ledeb using stepwise elution by high speed Countercurrent Chromatography
Journal of Liquid Chromatography & Related Technologies, 2007Co-Authors: Yun Wei, Yoichiro ItoAbstract:Abstract Preparative high-speed Countercurrent Chromatography was successfully used for isolation and purification of hyperoside and luteolin‐glucoside from Agrimonia pilosa Ledeb. The separation was performed by stepwise elution with a pair of two‐phase solvent systems composed of ethyl acetate‐methanol‐water at volume ratios of 50:1:50 and 5:1:5, which had been selected by analytical high-speed Countercurrent Chromatography (HSCCC). Using a preparative unit of the HSCCC centrifuge, about a 300 mg amount of the crude extract was separated, yielding 7.3 mg of hyperoside and 10.4 mg of luteolin‐glucoside at a high purity of over 97%.
Guoying Zhou - One of the best experts on this subject based on the ideXlab platform.
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separation of three polar compounds from rheum tanguticum by high speed Countercurrent Chromatography with an ethyl acetate glacial acetic acid water system
IEEE Journal of Solid-state Circuits, 2018Co-Authors: Tao Chen, Ping Wang, Nana Wang, Chongyang Sun, Xue Yang, Guoying ZhouAbstract:The separation of polar compounds by high‐speed Countercurrent Chromatography is still regarded as a challenge. In this study, an efficient strategy for the separation of three polar compounds from Rheum tanguticum has been successfully conducted by using high‐speed Countercurrent Chromatography. X‐5 macroporous resin Chromatography was used for the fast enrichment of the target compounds. Then, the target fraction was directly introduced into high‐speed Countercurrent Chromatography for separation using ethyl acetate/glacial acetic acid/water (100:1:100, v/v/v) as the solvent system. Consequently, three polar compounds including gallic acid, catechin, and gallic acid 4‐O‐β‐d‐(6′‐O‐galloyl) glucoside were obtained with purities higher than 98%. The results showed glacial acetic acid could be such an appropriate regulator for the ethyl acetate/water system. This study provides a reference for the separation of polar compounds from natural products by high‐speed Countercurrent Chromatography.
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Separation of three polar compounds from Rheum tanguticum by high-speed Countercurrent Chromatography with an ethyl acetate/glacial acetic acid/water system.
Journal of separation science, 2018Co-Authors: Tao Chen, Ping Wang, Nana Wang, Chongyang Sun, Xue Yang, Guoying ZhouAbstract:The separation of polar compounds by high‐speed Countercurrent Chromatography is still regarded as a challenge. In this study, an efficient strategy for the separation of three polar compounds from Rheum tanguticum has been successfully conducted by using high‐speed Countercurrent Chromatography. X‐5 macroporous resin Chromatography was used for the fast enrichment of the target compounds. Then, the target fraction was directly introduced into high‐speed Countercurrent Chromatography for separation using ethyl acetate/glacial acetic acid/water (100:1:100, v/v/v) as the solvent system. Consequently, three polar compounds including gallic acid, catechin, and gallic acid 4‐O‐β‐d‐(6′‐O‐galloyl) glucoside were obtained with purities higher than 98%. The results showed glacial acetic acid could be such an appropriate regulator for the ethyl acetate/water system. This study provides a reference for the separation of polar compounds from natural products by high‐speed Countercurrent Chromatography.
