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Counter current chromatography

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https://www.readbyqxmd.com/read/29771292/separation-of-four-flavonol-glycosides-from-solanum-rostratum-dunal-using-solvent-sublation-followed-by-hsccc-and-low-column-temperature-preparative-hplc
#1
Qian Shao, Lin Chang, Zhenya Wei, Yun Wei
Hyperoside, 3'-O-methylquercetin 3-O-β-D-galactopyranoside, astragalin and 3'-O-methylquercetin 3-O-β-D-glucopyranoside from an invasive weed Solanum rostratum Dunal were separated and purified successfully by high-speed counter-current chromatography (HSCCC) with a solvent system composed of n-hexane-ethyl acetate-methanol-water (1:7:1:7, v/v) and gradient elution mode preparative high-performance liquid chromatography (prep-HPLC) with low column temperature. In the sample pretreatment section, target compounds in aqueous extract of the weed were concentrated using solvent sublation...
May 16, 2018: Journal of Chromatographic Science
https://www.readbyqxmd.com/read/29751487/preparation-and-antioxidant-activity-of-ethyl-linked-anthocyanin-flavanol-pigments-from-model-wine-solutions
#2
Lingxi Li, Minna Zhang, Shuting Zhang, Yan Cui, Baoshan Sun
Anthocyanin-flavanol pigments, formed during red wine fermentation and storage by condensation reactions between anthocyanins and flavanols (monomers, oligomers, and polymers), are one of the major groups of polyphenols in aged red wine. However, knowledge of their biological activities is lacking. This is probably due to the structural diversity and complexity of these molecules, which makes the large-scale separation and isolation of the individual compounds very difficult, thus restricting their further study...
May 3, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29748985/preparative-isolation-of-ganoderic-acid-s-ganoderic-acid-t-and-ganoderol-b-from-ganoderma-lucidum-mycelia-by-high-speed-counter-current-chromatography
#3
Na Feng, Yutian Wei, Jie Feng, Qingjiu Tang, Zhong Zhang, Jingsong Zhang, Han Wei
Ganoderic acid S, ganoderic acid T, and ganoderal B are the main bioactive triterpenes of Ganoderma lucidum. In this study, mycelia of Ganoderma lucidum were obtained by two-stage fermentation and then extracted by ethanol and petroleum ether sequentially to obtain crude triterpenes. The crude sample was further purified by recycling high-speed counter-current chromatography (HSCCC) with n-hexane: ethyl acetate: methanol: water (7:12:11:5, v/v/v/v) as the optimized two-phase solventsystem. 16.4 mg of ganoderol B with the purity of 90...
May 10, 2018: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/29738963/purification-of-r-phycoerythrin-from-gracilaria-lemaneiformis-by-centrifugal-precipitation-chromatography
#4
Dongyu Gu, Rodrigo Lazo-Portugal, Chen Fang, Zhantong Wang, Ying Ma, Martha Knight, Yoichiro Ito
Centrifugal precipitation chromatography (CpC) is a powerful chromatographic technique invented in the year 2000 but so far very little applied. The method combines dialysis, counter-current and salting out processes. The separation rotor consists of two identical spiral channels separated by a dialysis membrane (6-8 K MW cut-off) in which the upper channel is eluted with an ammonium sulfate gradient and the lower channel with water, and the mixtures are separated according to their solubility in ammonium sulfate as a chromatographic technique...
May 1, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29680742/ph-zone-refining-counter-current-chromatography-with-a-hydrophilic-organic-salt-containing-two-phase-solvent-system-for-preparative-separation-of-polar-alkaloids-from-natural-products
#5
Denglang Zou, Yurong Du, Jianyuan Kuang, Shihao Sun, Jianbin Ma, Renwang Jiang
This study presents an efficient strategy based on pH-zone-refining counter-current chromatography with a hydrophilic organic/salt-containing two-phase system composed of acetonitrile, sodium chloride and water for preparative separation of polar alkaloids from natural products. Acetonitrile-sodium chloride-water system provides a wider range of polarity for polar alkaloids than classical aqueous two-phase systems. It gets rid of the effect of free hydrogen ion, strong ionic strength, hold low viscosity and the sharp retainer border could be formed easily...
April 10, 2018: Journal of Chromatography. A
https://www.readbyqxmd.com/read/29673766/an-easy-to-use-calculating-machine-to-simulate-steady-state-and-non-steady-state-preparative-separations-by-multiple-dual-mode-counter-current-chromatography-with-semi-continuous-loading-of-feed-mixtures
#6
Artak E Kostanyan, Oleg N Shishilov
Multiple dual mode counter-current chromatography (MDM CCC) separation processes with semi-continuous large sample loading consist of a succession of two counter-current steps: with "x" phase (first step) and "y" phase (second step) flow periods. A feed mixture dissolved in the "x" phase is continuously loaded into a CCC machine at the beginning of the first step of each cycle over a constant time with the volumetric rate equal to the flow rate of the pure "x" phase. An easy-to-use calculating machine is developed to simulate the chromatograms and the amounts of solutes eluted with the phases at each cycle for steady-state (the duration of the flow periods of the phases is kept constant for all the cycles) and non-steady-state (with variable duration of alternating phase elution steps) separations...
April 10, 2018: Journal of Chromatography. A
https://www.readbyqxmd.com/read/29629211/rapid-screening-and-preparative-isolation-of-antioxidants-from-alpinia-officinarum-hance-using-hsccc-coupled-with-dpph-hplc-assay-and-evaluation-of-their-antioxidant-activities
#7
Lei Fang, Hua Zhang, Jie Zhou, Yanling Geng, Xiao Wang
An efficient method using high-speed counter-current chromatography (HSCCC) coupled with DPPH-HPLC assay has been developed for rapid screening and preparative isolation of antioxidants from ethyl acetate fraction of Alpinia officinarum Hance. Target-guided by DPPH-HPLC assay, two antioxidants, galangin and kaempferide, were targeted and further separated with purities of 99.3% and 98.5% by HSCCC using petroleum ether-ethyl acetate-methanol-water (0.8 : 1 : 1 : 0.8, v / v ) as the solvent system. The antioxidant activities of galangin and kaempferide were further evaluated by measuring their inhibiting effects on superoxide anion radical, hydroxyl radical, and hydrogen peroxide in different luminol chemiluminescence (CL) systems...
2018: Journal of Analytical Methods in Chemistry
https://www.readbyqxmd.com/read/29522957/protein-a-affinity-chromatography-of-chinese-hamster-ovary-cho-cell-culture-broths-containing-biopharmaceutical-monoclonal-antibody-mab-experiments-and-mechanistic-transport-binding-and-equilibrium-modeling
#8
Matic Grom, Mirijam Kozorog, Simon Caserman, Andrej Pohar, Blaž Likozar
Protein A-based affinity chromatography is a highly-efficient separation method to capture, purify and isolate biosimilar monoclonal antibodies (mAb) - an important medical product of biopharmaceutical industrial manufacturing. It is considered the most expensive step in purification downstream operations; therefore, its performance optimization offers a great cost saving in the overall production expenditure. The biochemical mixture-separating specific interaction experiments with Chinese hamster ovary (CHO) cell culture harvest, containing glycosylated extracellular immunoglobulins (Ig), were made using five different state-of-the-art commercial resins...
April 15, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29498678/isolation-and-purification-of-two-isoflavones-from-hericium-erinaceum-mycelium-by-high-speed-counter-current-chromatography
#9
Jinzhe He, Peng Fan, Simin Feng, Ping Shao, Peilong Sun
High-speed counter-current chromatography (HSCCC) was used to separate and purify two isoflavones for the first time from Hericium erinaceum ( H. erinaceum ) mycelium using a two-phase solvent system composed of chloroform-dichloromethane-methanol-water (4:2:3:2, v / v / v / v ). These two isoflavones were identified as genistein (4',5,7-trihydroxyisoflavone, C15 H10 O₅) and daidzein (4',7-dihydroxyisoflavone, C15 H10 O₄), using infrared spectroscopy (IR), electro-spary ionisation mass (ESI-MS), ¹H-nuclear magnetic resonance (NMR) and 13 C-NMR spectra...
March 2, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29484987/determination-and-isolation-of-four-anti-tumour-saponins-from-lonicera-macranthoides-by-hplc-esi-qtof-ms-and-hsccc
#10
Xuehui Liu, Rongrong Zhou, Bingbing Shen, Lin Chen, Qingyijun Zhou, Dan Wan, Luqi Huang, Shuihan Zhang
BACKGROUND: Lonicera macranthoides is a Chinese herb that contains a large number of bioactive spanions possessing important pharmacological activities, such as anti-tumour activity. However, detailed information about their anti-tumor activity and bioactive compounds is limited. METHODS: In order to evaluate the scientific basis, the method of high-speed counter-current chromatography (HSCCC) combined with high performance liquid chromatography mass spectrometry (HPLC-ESI-QTOF/MS) has been developed to separate, purify and analyze saponins from Lonicera macranthoides...
2017: Current Pharmaceutical Biotechnology
https://www.readbyqxmd.com/read/29462864/semi-preparative-separation-of-10-caffeoylquinic-acid-derivatives-using-high-speed-counter-current-chromatogaphy-combined-with-semi-preparative-hplc-from-the-roots-of-burdock-arctium-lappa-l
#11
Zhenjia Zheng, Xiao Wang, Pengli Liu, Meng Li, Hongjing Dong, Xuguang Qiao
Burdock roots are healthy dietary supplements and a kind of famous traditional Chinese medicine, which contains large amounts of caffeoylquinic acid derivatives. However, little research has been reported on the preparative separation of these compounds from burdock roots. In the present study, a combinative method of HSCCC and semi-preparative HPLC was developed for the semi-preparative separation of caffeoylquinic acid derivatives from the burdock roots. The ethyl acetate extract of burdock roots was first fractionated by MCI macroporous resin chromatography and give three fractions (Fr...
February 15, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29457870/effect-of-the-flow-profile-on-separation-efficiency-in-pressure-assisted-reversed-polarity-capillary-zone-electrophoresis-of-anions-simulation-and-experimental-evaluation
#12
Gabor Jarvas, Marton Szigeti, Andras Guttman
Capillary electrophoresis connected to electrospray ionization mass spectrometry is a promising combination to analyze complex biological samples. The use of sheathless electrospray ionization interfaces, such as a porous nanoelectrospray capillary emitter, requires the application of forward flow (either by pressure or electroosmosis) to maintain the electrospray process. The analysis of solute molecules with strong negative charges (e.g., aminopyrenetrisulfonate labeled glycans) necessitates a reversed-polarity capillary electrophoresis separation mode, in which case the electroosmotic flow is counter current, thus pressure assistance is necessary...
February 19, 2018: Journal of Separation Science
https://www.readbyqxmd.com/read/29456156/a-multilayer-coil-in-type-i-counter-current-chromatography
#13
Yi Yang, Jiao Yang, Chen Fang, Dongyu Gu, Ying Ma, Yoichiro Ito
In the present study, a novel model of type-I counter-current chromatography was developed to simplify the separation column manufacture and extend its application ranges. In this system, a multilayer coil was used as the separation column of type-I counter-current chromatography for the first time. The chromatographic performance of this apparatus was evaluated in terms of retention of the stationary phase (Sf), theoretical plate (N) and peak resolution (Rs) using dipeptides and DNP-amino acids as test samples with two classic solvent systems composed of 1-butanol-acetic acid-water (4:1:5, v/v) (BAW) and hexane-ethyl acetate-methanol-0...
March 16, 2018: Journal of Chromatography. A
https://www.readbyqxmd.com/read/29442431/elution-extrusion-countercurrent-chromatography-separation-of-six-pairs-of-isomeric-iridoids-from-cornus-officinalis-sieb-et-zucc-guided-by-ion-current-extraction-in-mass-spectrometry
#14
Jinru Liang, Wenji Sun
A mass spectrometry-guided elution-extrusion countercurrent chromatography protocol was developed to separate chemical components from Cornus officinalis Sieb. et Zucc. In this study, ion current extraction, a mass spectrometry-based data postacquisition method, was utilized to boost the separation power and scope of countercurrent chromatography technique. As a peak repicking and denoising tool, ion current extraction was carried out to process the liquid chromatography with mass spectrometry and the countercurrent chromatography with mass spectrometry data...
February 14, 2018: Journal of Separation Science
https://www.readbyqxmd.com/read/29439422/separation-and-purification-of-fructo-oligosaccharide-by-high-speed-counter-current-chromatography-coupled-with-precolumn-derivatization
#15
Wenjuan Duan, Wenhua Ji, Yuanan Wei, Ruixuan Zhao, Zijian Chen, Yanling Geng, Feng Jing, Xiao Wang
High-speed counter-current chromatography (HSCCC) coupled with precolumn derivatization was developed for isolating and purifying fructo-oligosaccharides (FOSs). Firstly, the total FOSs were precolumn derivatized and then separated by high-speed counter-current chromatography (HSCCC) with two-phase solvent system petroleum ether- n -butanol-methanol-water (3:2:1:4, v / v ). Secondly, the obtained compounds were deacetylated and the fructo-oligosaccharides (FOSs) with high purity were obtained. Their structures were identified by mass spectrometry (MS) and nuclear magnetic resonance (NMR)...
February 10, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29389842/dihydrocodeine-overdoses-in-a-neonate-and-in-a-14-year-old-girl-who-were-both-genotyped-as-cytochrome-p450-2d6-1-10-36-comparing-developmental-ages-and-drug-monitoring-data-with-the-results-of-pharmacokinetic-modeling
#16
Makiko Shimizu, Tatsuki Kondo, Tetsuya Fukuoka, Toshihiro Tanaka, Hiroshi Yamazaki
A high activity of cytochrome P450 2D6 (CYP2D6) reportedly leads to toxicity of dihydrocodeine/codeine by increasing toxic potential of their metabolite dihydromorphine/morphine, which are further metabolized to highly active dihydromorphine 6-O-glucuronide and the less active morphine 3-O-glucorinide but rapidly excreted into urine as water-soluble forms. A case of acute respiratory depression after administration of prescribed dihydrocodeine phosphate (2.0 mg/d divided twice a day for 2 days) to a 1-month-old baby boy genotyped as CYP2D6*1/*10-*36 is described...
April 2018: Therapeutic Drug Monitoring
https://www.readbyqxmd.com/read/29382097/nigella-damascena-l-essential-oil-a-valuable-source-of-%C3%AE-elemene-for-antimicrobial-testing
#17
Elwira Sieniawska, Rafal Sawicki, Joanna Golus, Marta Swatko-Ossor, Grazyna Ginalska, Krystyna Skalicka-Wozniak
The most commonly used plant source of β-elemene is Curcuma wenyujin Y. H. Chen & C. Ling (syn. of Curcuma aromatic Salisb.) with its content in supercritical CO₂ extract up to 27.83%. However, the other rich source of this compound is Nigella damascena L. essential oil, in which β-elemene accounts for 47%. In this work, the effective protocol for preparative isolation of β-elemene from a new source- N. damascena essential oil-using high performance counter-current chromatography HPCCC was elaborated...
January 28, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29370920/use-of-counter-current-chromatography-as-a-selective-extractor-for-the-diterpenequinone-7%C3%AE-hydroxyroyleanone-from-tetradenia-riparia
#18
Jonatas Vicente Milato, Raphael Salles Ferreira Silva, Fabiana de Souza Figueiredo, Debora de Almeida Azevedo, Carlos Alexandre Bulchi Ribeiro, Gilda Guimarães Leitão
A solvent system was developed for selective isolation by high-speed counter-current chromatography (HSCCC) of the benzoquinone 7α-hydroxyroileanone, 1, a bioactive diterpene from a dichloromethane extract of Tetradenia riparia leaves. Several solvent systems were initially studied, including hexane-ethyl acetate-methanol-water in several ratios, hexane-acetone-methanol-water, hexane-ethanol-water and hexane-acetonitrile-methanol, which gave recovery rates for the target compound between 13.4 and 35.9%. The new solvent system hexane-5% aqueous Na2 CO3 (1:1) was developed based on the chemical ionization reaction of the benzoquinone hydroxyl group in the basic pH of the carbonate solution, prompted by the extraction procedure used for the extraction of lapachol (a natural naphtoquinone) from a Tabebuia species wood...
February 16, 2018: Journal of Chromatography. A
https://www.readbyqxmd.com/read/29368235/dual-effect-of-histidine-on-polysorbate-20-stability-mechanistic-studies
#19
Lin Zhang, Sandeep Yadav, Y John Wang, Olivier Mozziconacci, Christian Schӧneich
PURPOSE: L-Histidine (L-His) and polysorbate 20 (PS20) are two excipients frequently included in parenteral products to stabilize biotherapeutics. The objective of the current work was to investigate the impact of L-His on PS20 stability in aqueous solutions when subjected to forced oxidation and accelerated stability testing. METHODS: The stability of PS20 in L-His buffer was compared with that in acetate buffer. Forced oxidation of PS20 in these two buffer systems was initiated by a free radical generator, 2,2'-azobis (2-amidinopropane) hydrochloride (AAPH), while accelerated stability tests were carried out at 40°C...
January 16, 2018: Pharmaceutical Research
https://www.readbyqxmd.com/read/29330916/separation-of-three-polar-compounds-from-rheum-tanguticum-by-high-speed-countercurrent-chromatography-with-an-ethyl-acetate-glacial-acetic-acid-water-system
#20
Tao Chen, Ping Wang, Nana Wang, Chongyang Sun, Xue Yang, Hongmei Li, Guoying Zhou, Yulin Li
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...
January 13, 2018: Journal of Separation Science
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