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Counter current chromatography

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https://www.readbyqxmd.com/read/28106330/separation-and-purification-of-two-taxanes-and-one-xylosyl-containing-taxane-from-taxus-wallichiana-zucc-a-comparison-between-high-speed-counter-current-chromatography-and-reversed-phase-flash-chromatography
#1
Junfei Tao, Rongwei Yan, Leilei Zhao, Dongmei Wang, Xinjun Xu
10-Deacetylbaccatin III, an important semi-synthetic precursor of paclitaxel and docetaxel, can be extracted from Taxus wallichiana Zucc.. A process for the isolation and purification of 10-deacetylbaccatin III (1), baccatin III (2) and 7β-xylosyl-10-deacetyltaxol (3) from the leaves and branches of Taxus wallichiana Zucc. via macroporous resin column chromatography combined with high-speed counter-current chromatography or reversed-phase flash chromatography was developed in this study. After fractionation by macroporous resin column chromatography, 80% methanol fraction was selected based on high-performance liquid chromatography and liquid chromatography with mass spectrometry qualitative analysis...
January 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28049583/purification-of-semiconducting-single-walled-carbon-nanotubes-by-spiral-counter-current-chromatography
#2
Martha Knight, Rodrigo Lazo-Portugal, Saeyoung Nate Ahn, Steingrimur Stefansson
Over the last decade man-made carbon nanostructures have shown great promise in electronic applications, but they are produced as very heterogeneous mixtures with different properties so the achievement of a significant commercial application has been elusive. The dimensions of single-wall carbon nanotubes are generally a nanometer wide, up to hundreds of microns long and the carbon nanotubes have anisotropic structures. They are processed to have shorter lengths but they need to be sorted by diameter and chirality...
December 24, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27993866/separation-and-purification-of-ombuoside-from-gynostemma-pentaphyllum-by-microwave-assisted-extraction-coupled-with-high-speed-counter-current-chromatography
#3
Wenhui Jiang, Hu Shan, Jiying Song, Haitao Lü
A rapid and efficient method for the separation and purification of ombuoside from Gynostemma pentaphyllum by microwave-assisted extraction coupled with high-speed counter-current chromatography (HSCCC) was successfully developed. Using an orthogonal array design L9 (3(4)), the extraction conditions, including microwave power, irradiation time, solid-to-liquid ratio and extraction times, were optimized. Ombuoside was isolated and purified from the crude extraction by HSCCC with two-phase solvent system composed of n-hexane:ethyl acetate:ethanol:water (5:6:5:5, v/v) in a single run...
January 2017: Journal of Chromatographic Science
https://www.readbyqxmd.com/read/27988077/alternating-isocratic-and-step-gradient-elution-high-speed-counter-current-chromatography-for-the-isolation-of-minor-phenolics-from-ormocarpum-kirkii-bark
#4
Eutrophe Le Doux Kamto, Tatiane S C Carvalho, Joséphine Ngo Mbing, Marie C N Matene, Dieudonné E Pegnyemb, Gilda G Leitão
A total of 14 compounds were isolated from the ethanol bark extract of O. kirkii S. Moore (Fabaceae) by alternating isocratic and step gradient elution high-speed counter-current chromatography (HSCCC) methods, using several solvent systems with reference to the polarity of compounds being purified. The extract was successively fractionated with generic solvent systems including n-hexane-ethanol-water (4:2:2) and ethyl acetate-water (1:1). Resulting fractions were further purified using the following preparative gradient elution consisting of ethyl acetate-n-butanol-water (X:Y:10), (X:Y=9:1 (I); 8:2 (II); 7:3 (III); 6:4 (IV); 5:5 (V); 4:6 (VI) 3:7 (VII) and n-hexane- ethyl acetate-methanol-water (1:X:1:1), X=1, 2, 2...
January 13, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27977908/integrated-continuous-processing-of-proteins-expressed-as-inclusion-bodies-gcsf-as-a-case-study
#5
Nikhil Kateja, Harshit Agarwal, Vishwanath Hebbi, Anurag S Rathore
Affordability of biopharmaceuticals continues to be a challenge, particularly in developing economies. This has fuelled advancements in manufacturing that can offer higher productivity and better economics without sacrificing product quality in the form of an integrated continuous manufacturing platform. While platform processes for monoclonal antibodies have existed for more than a decade, development of an integrated continuous manufacturing process for bacterial proteins has received relatively scant attention...
December 15, 2016: Biotechnology Progress
https://www.readbyqxmd.com/read/27935227/preparative-isolation-of-bioactive-compounds-from-stem-bark-of-juglans-mandshurica-by-using-high-speed-counter-current-chromatography
#6
Yuwei Zhang, Hua Lin, Shanshan Li, Jianbo Chen, Yinshi Sun, Yuxin Li
High-speed counter-current chromatography was applied for the first time to the separation and purification of bioactive compounds contained in the stem bark of Juglans mandshurica Maxim. Silica gel column chromatography was first used to obtain three composition-enriched target fractions from a crude J. mandshurica methanol extract. Three independent high-speed counter-current chromatography processes were then used to further isolate 13 bioactive compounds, namely, six galloyl glucose derivatives, three flavonones, three naphthoquinones, and ethyl gallate...
December 9, 2016: Journal of Separation Science
https://www.readbyqxmd.com/read/27932083/room-temperature-ionic-liquids-based-salting-in-strategy-for-counter-current-chromatography-in-the-separation-of-arctiin
#7
Yanyan Wang, Lihong Zhang, Dingding Wang, Xiuyun Guo, Shihua Wu
Counter-current chromatography (CCC) is a solid support-free liquid-liquid partition chromatography and has wide applications. However, CCC separation is still a challenging process and the selection of appropriate solvent system for separation of target compound(s) is still relatively time-consuming. In this work, we introduced a room temperature ionic liquids-based salting-in strategy for the rapid selection of suitable solvent systems for CCC separation. In the randomly selected solvent systems, such as ethyl acetate-water, n-butanol-water, n-pentanol-water, n-hexanol-water, and n-octanol-water, several ionic liquids such as [AMIM]Cl, [MAMIM]Cl, and [BMIM]Cl can increase the solubility of the solutes in the lower phase, which made a dose-dependent decreasing of partition coefficient of solute in the two-phase solvent system...
December 23, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27884427/sample-injection-strategy-to-increase-throughput-in-counter-current-chromatography-case-study-of-honokiol-purification
#8
Aihua Peng, Peter Hewitson, Haoyu Ye, Liansuo Zu, Ian Garrard, Ian Sutherland, Lijuan Chen, Svetlana Ignatova
Counter-current chromatography (CCC) has been widely used as a preparative separation method to purify natural products from plant extracts and fermentation broths. Traditionally, throughput optimization in CCC has focused on sample concentration and sample volume. In this paper sample injection was considered as consisting of three variables: injection flow rate, post-injection flow rate and sample solvent. The effects of these parameters were studied using a honokiol purification from a Magnolia officinalis bark extract as a case study aiming to achieve the highest throughput/yield ratio for greater than 99% purity of this potential anti-cancer drug obtained for submission to the Chinese FDA...
December 9, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27867270/preparation-of-sesquiterpenoids-from-tussilago-farfara-l-by-high-speed-counter-current-chromatography
#9
Kun Cao, Yi Xu, Tian-Ming Zhao, Qing Zhang
BACKGROUND: Sesquiterpenoids, such as tussilagone, has effects of raising blood pressure, antiplatelet aggregation, and anti-inflammation activities, which is regarded as index compound for quality control of Tussilago farfara L. OBJECTIVE: This study was aimed to obtain an effective method for fast isolation of sesquiterpenoids from T. farfara L. by high-speed counter-current chromatography (HSCCC). MATERIALS AND METHODS: A solvent optimization method for HSCCC was presented, i...
October 2016: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/27818942/a-simple-tool-for-tubing-modification-to-improve-spiral-high-speed-counter-current-chromatography-for-protein-purification
#10
Yoichiro Ito, Xiaofeng Ma, Robert Clary
A simple tool is introduced which can modify the shape of tubing to enhance the partition efficiency in high-speed countercurrent chromatography. It consists of a pair of interlocking identical gears, each coaxially holding a pressing wheel to intermittently compress plastic tubing in 0 - 10 mm length at every 1 cm interval. The performance of the processed tubing is examined in protein separation with 1.6 mm ID PTFE tubing intermittently pressed in 3 mm and 10 mm width both at 10 mm intervals at various flow rates and revolution speeds...
2016: Current Chromatography
https://www.readbyqxmd.com/read/27765425/modeling-of-preparative-closed-loop-recycling-liquid-liquid-chromatography-with-specified-duration-of-sample-loading
#11
Artak E Kostanyan
The closed-loop recycling counter-current chromatography (CLR CCC) is performed in several consecutive separation stages. First, the loop is opened, and within a specified time the solution of solutes in the mobile phase is continuously fed to the column. After the solutes loading is finished, the loop is closed, and the first separation stage starts. After a certain number of cycles the first fraction of solutes is eluted, the loop is closed, and the second separation stage starts, and so on. In this study, simple equations are presented allowing the simulation of such separation processes...
November 4, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27765421/development-of-a-high-speed-counter-current-chromatography-system-with-cu-ii-chiral-ionic-liquid-complexes-and-hydroxypropyl-%C3%AE-cyclodextrin-as-dual-chiral-selectors-for-enantioseparation-of-naringenin
#12
Shanshan Wang, Chao Han, Sisi Wang, Lijuan Bai, Shanshan Li, Jianguang Luo, Lingyi Kong
Cu(II) complexed amino acid ionic liquid, Cu(II)-[1-butyl-3-methylimidazolium][L-Pro] (Cu(II)-[BMIm][L-Pro]), was successfully adopted as chiral ligand to improve the enantioseparation efficiency in high speed counter-current chromatography (HSCCC). For the enantioseparation of intractable naringenin (NRG) racemic mixtures, Cu(II)-[BMIm][L-Pro] coupled with hydroxypropyl-β-cyclodextrin (HP-β-CD) was successfully applied as dual chiral selectors in HSCCC. The influence of important parameters, including the concentration of the chiral selectors, the pH value, and the temperature were investigated...
November 4, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27765243/preparative-high-speed-counter-current-chromatography-separation-of-grape-seed-proanthocyanidins-according-to-degree-of-polymerization
#13
Shuting Zhang, Lingxi Li, Yan Cui, Lanxin Luo, Yuanyuan Li, Peiyu Zhou, Baoshan Sun
Separation of plant proanthocyanidins remains a major challenge for scientists due to the structural diversity and complexity. In this work, a new and effective method was developed for preparative separation of grape seed proanthocyanidins (GSPs) according to degree of polymerization (DP) by high-speed counter-current chromatography (HSCCC). Under the optimized HSCCC conditions, GSPs could be separated into seven distinct fractions (F1-F7) with mean degree of polymerization in increasing order, from 1.44 to 6...
March 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/27753202/rapid-screening-separation-and-detection-of-hydroxyl-radical-scavengers-from-total-flavonoids-of-ginkgo-biloba-leaves-by-chromatography-combined-with-molecular-devices
#14
Jing Wang, Meizhu Zheng, Lina Chen, Zhiqiang Liu, Yuchi Zhang, Chun-Ming Liu, Shu Liu
Hydroxyl radicals are the most reactive free radical of human body, a strong contributor to tissue damage. In this study, liquid chromatography coupled to electrospray ionization mass spectrometry was applied to screen and identify hydroxyl radical scavengers from the total flavonoids of Ginkgo biloba leaves, and high-performance counter current chromatography was used to separate and isolate the active compounds. Furthermore, molecular devices were used to determine hydroxyl radical scavenging activities of the obtained hydroxyl radical scavengers and other flavonoids from G...
November 2016: Journal of Separation Science
https://www.readbyqxmd.com/read/27748050/first-separation-of-four-aromatic-acids-and-two-analogues-with-similar-structures-and-polarities-from-clematis-akebioides-by-high-speed-counter-current-chromatography
#15
Chengcheng Gong, Tao Chen, Huifeng Chen, Shanshan Zhang, Xinzhu Wang, Weiqing Wang, Jing Sun, Yulin Li, Zhixin Liao
In this paper, we report an efficient method by high-speed counter-current chromatography for the first separation of four aromatic acids and two analogs with similar structures and polarities from Clematis akebioides. First, the ethyl acetate extract was treated by silica gel column chromatography to enrich the target compounds. And then the fraction with target compounds were purified by high-speed counter-counter chromatography using a two-phase solvent system consisting of chloroform/acetonitrile/water (10:6:4, v/v)...
December 2016: Journal of Separation Science
https://www.readbyqxmd.com/read/27717742/effect-of-intraocular-pressure-iop-and-choroidal-circulation-on-controlled-episcleral-drug-delivery-to-retina-vitreous
#16
Jie Li, Bifei Lan, Xiaoli Li, Shumao Sun, Ping Lu, Lingyun Cheng
Transscleral drug delivery may become a safe alternative to the intravitreal injection for chronic retinal diseases such as age-related macular degeneration or diabetic macular edema. However, the drug delivered onto the sclera subjects to vigorous clearance by episcleral and choroidal circulation; in addition, the penetration from episclera to retina needs to overcome counter-directional ocular fluid current driven by intraocular pressure (IOP) as well as unfavorable drug disposition exerted by drug transporters before the drug reach retina...
December 10, 2016: Journal of Controlled Release: Official Journal of the Controlled Release Society
https://www.readbyqxmd.com/read/27700988/preparative-separation-of-cacao-bean-procyanidins-by-high-speed-counter-current-chromatography
#17
Lingxi Li, Shuting Zhang, Yan Cui, Yuanyuan Li, Lanxin Luo, Peiyu Zhou, Baoshan Sun
In this work, an efficient method for preparative separation of procyanidins from raw cacao bean extract by high-speed counter-current chromatography (HSCCC) was developed. Under the optimized solvent system of n-hexane-ethyl acetate-water (1:50:50, v/v/v) with a combination of head-tail and tail-head elution modes, various procyanidins fractions with different polymerization degrees were successfully separated. UPLC, QTOF-MS and (1)H NMR analysis verified that these fractions contained monomer up to pentamer respectively...
November 15, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/27689891/simultaneous-quantification-of-antioxidant-compounds-in-phellinus-igniarius-using-ultra-performance-liquid-chromatography-photodiode-array-detection-electrospray-ionization-tandem-mass-spectrometry
#18
Dan Shou, Yu Dong, Nani Wang, Hongyu Li, Yang Zhang, Yan Zhu
Natural antioxidants are widely used in the life sciences. Phellinus igniarius is a historically used natural antioxidant containing a variety of active compounds. Phenols, particularly Inoscavin A and Hypholomine B, are found in the high concentrations. Better quantitative methods are needed to perform quality control in order to support further research of this mushroom. An ultra-performance liquid chromatography method coupled to photodiode-array detection and an electrospray ionization tandem mass spectrometry method (UPLC-PAD-MS) was developed to simultaneously quantify Inoscavin A and Hypholomine B levels in the medicinal fungus Phellinus igniarius...
2016: PloS One
https://www.readbyqxmd.com/read/27670752/preparation-of-salvianolic-acid-a-by-the-degradation-reaction-of-salvianolic-acid-b-in-subcritical-water-integrated-with-ph-zone-refining-counter-current-chromatography
#19
Huaizhi Li, Yan Cheng, Hongjing Dong, Xiao Wang, Jia Li, Qianshan Gao
Salvianolic acid A is the major bioactive compound in Danshen, however, due to the chemical instability and low content in Danshen, it is difficult to extract amount of salvianolic acid A. Therefore, this study was to establish an effective strategy for obtaining adequate amount of salvianolic acid A, subcritical water extraction was used to degrade salvianolic acid B and prepare salvianolic acid A. Different reaction conditions including temperature, time, concentration and pH value in subcritical water were investigated...
October 14, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27667123/spiral-counter-current-chromatography-design-development-application-and-challenges
#20
REVIEW
Xin-Yi Huang, Xiao-Ming Sun, Dong Pei, Duo-Long Di
Depending on the rapid growth in the radial gradient of the centrifugal force, spiral counter-current chromatography can greatly improve the retention of stationary phase, especially for the aqueous two-phase systems with ultra-polar and high viscosity that are not well retained in the conventional multilayer coils counter-current chromatography. As a result, it is an attractive and alternative technology that is suited for separation of hydrophilic compounds and has led to many exciting progress in recent years...
September 26, 2016: Journal of Separation Science
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