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Counter current chromatography

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https://www.readbyqxmd.com/read/28441546/isolation-of-new-polyacetylenes-from-the-roots-of-eurycoma-longifolia-via-high-speed-counter-current-chromatography
#1
Minglong Wang, Huijuan Zou, Qibin Chen, Jianguo Cao, Haji Akber Aisa, Guozheng Huang
Eurycoma longifolia is a tropical plant of diverse applications in folk medicine, which occurs in Southeast Asia. In this study, pre-purified fraction (0.86g) of the crude extracts from the roots of E. longifolia, was subjected to preparative high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of hexane-ethyl acetate-methanol-water (HEMWat) at a volume ratio of 5:2:5:2 (v/v). Longifolione A (1, 19mg, purity 96.0%) and longifolione C (3, 317mg, purity 96.2%), together with longifolione B (2, purity 77...
April 1, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28427287/downstream-protein-separation-by-surfactant-precipitation-a-review
#2
Fadzlie Wong Faizal Wong, Arbakariya B Ariff, David C Stuckey
In a conventional protein downstream processing (DSP) scheme, chromatography is the single most expensive step. Despite being highly effective, it often has a low process throughput due to its semibatch nature, sometimes with nonreproducible results and relatively complex process development. Hence, more work is required to develop alternative purification methods that are more cost-effective, but exhibiting nearly comparable performance. In recent years, surfactant precipitation has been heralded as a promising new method for primary protein recovery that meets these criteria and is a simple and cost-effective method that purifies and concentrates...
April 21, 2017: Critical Reviews in Biotechnology
https://www.readbyqxmd.com/read/28416338/separation-and-purification-of-polyphenols-from-red-wine-extracts-using-high-speed-counter-current-chromatography
#3
Yuanyuan Li, Lingxi Li, Yan Cui, Shuting Zhang, Baoshan Sun
Polyphenols are important compounds of red wine owing to their contribution to sensory properties and antioxidant activities. In this study, high-speed counter-current chromatography (HSCCC) coupled with semi-preparative HPLC was used for large-scale separation and purification of polyphenols from red wine extracts. With the solvent system of hexane-ethyl acetate-water (1-50-50), various oligomeric procyanidins including monomer catechin, epicatechin, dimers B1, B2; phenolic acids including coutaric acid, caftaric acid and other type of polyphenols were largely separated within 370min and most of these compounds presented high yields (0...
March 12, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28407532/rational-approach-to-solvent-system-selection-for-liquid-liquid-extraction-assisted-sample-pretreatment-in-counter-current-chromatography
#4
Jiajia Wang, Dongyu Gu, Miao Wang, Xinfeng Guo, Haoquan Li, Yue Dong, Hong Guo, Yi Wang, Mengqi Fan, Yi Yang
A rational liquid-liquid extraction approach was established to pre-treat samples for high-speed counter-current chromatography (HSCCC). n-Hexane-ethyl acetate-methanol-water (4:5:4:5, v/v) and (1:5:1:5, v/v) were selected as solvent systems for liquid-liquid extraction by systematically screening K of target compounds to remove low- and high-polarity impurities in the sample, respectively. After liquid-liquid extraction was performed, 1.4g of crude sample II was obtained from 18.5g of crude sample I which was extracted from the flowers of Robinia pseudoacacia L...
April 4, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28371341/preparative-separation-of-phytosterol-analogues-from-green-alga-chlorella-vulgaris-using-recycling-counter-current-chromatography
#5
Jianbing Wu, Chunping Liu, Yanbin Lu
The unicellular alga Chlorella vulgaris is a well-known health food. It has been proven that the minor phytosterols, ergosterol and its analogue, are an important class of bioactive substances in C. vulgaris. In this work, a recycling counter-current chromatographic approach was proposed for preparative separation of two analogue sterols from crude extract of C. vulgaris. The separation unit was set up with a type-J instrument coupled with a column switching valve. A two-phase solvent system composed of n-hexane/dichloromethane/acetonitrile (10:3:7, v/v) was selected and optimized...
March 31, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28332768/separation-of-caffeoylquinic-acids-and-flavonoids-from-asteris-souliei-by-high-performance-counter-current-chromatography-and-their-anti-inflammatory-activity-in-vitro
#6
Qiang Zhang, He-Ying Pei, Kai Chen, Huan Tang, Bo Wu, Ming-Hai Tang, Ai-Hua Peng, Hao-Yu Ye, Li-Juan Chen
Eleven compounds were successfully separated from Asteris souliei by using a two-step high-performance counter-current chromatography method. The first step involved a reversed phase isocratic counter-current chromatography separation using hexane/ethyl acetate/methanol/water (1:0.8:1:1 v/v/v/v), which produced three fractions, the first two of which were mixtures. The second step used step-gradient reversed-phase counter-current chromatography with hexane/butanol/ethyl acetate/methanol/water (1:0.5:3.5:1:4 v/v/v/v/v) initially followed by hexane/ethyl acetate/methanol/water (1:2:1:2 v/v/v/v) to separate Fraction 1 into seven compounds; and hexane/ethyl acetate/methanol/water (1:1:1:1...
March 23, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28273835/identifying-natural-synergist-from-pongamia-pinnata-using-high-speed-counter-current-chromatography-combined-with-isobolographic-analysis
#7
Hao Yin, Yubai Wei, Rouwen Chen, Si Zhang, Lijuan Long, Hang Yin, Xinpeng Tian, Weihong He
For identifying the synergistic compounds from Pongamia pinnata, an approach based on high-speed counter-current chromatography (HSCCC) combined with isobolographic analysis was designed to detect the synergistic effects in the complex mixture [...].
March 3, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28259459/concentrical-coils-counter-current-chromatography-for-natural-products-isolation-salvia-miltiorrhiza-bunge-as-example
#8
Lihong Zhang, Yanyan Wang, Xiuyun Guo, Shihua Wu
Countercurrent chromatography (CCC) is an efficient separation technique without the solid support matrix, largely depending on the partition of two-immiscible liquid phases in the separation column. Since the helical coil planet centrifuge was invented in early 1970s by Yoichiro Ito, a series of coils columns, including spiral coils and conical coils columns have been developed for CCC separation. In this work, we introduced a new simple and efficient concentrical coils column for CCC separation, which was prepared by winding the whole polytetrafluoroethylene (PTFE) tube into the circular grooves from the rotation axis in the same direction...
March 31, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28236459/k-targeted-strategy-for-isolation-of-phenolic-alkaloids-of-nelumbo-nucifera-gaertn-by-counter-current-chromatography-using-lysine-as-a-ph-regulator
#9
Yanyan Wang, Lihong Zhang, Hui Zhou, Xiuyun Guo, Shihua Wu
Counter-current chromatography (CCC) is an efficient liquid-liquid partition chromatography technique without support matrix. Despite there are many significant advancements in the CCC separation of natural products especially for non-ionic neutral compounds, CCC isolation of ionic compounds including alkaloids is still a challenging process guide by classical partition coefficients (K) or distribution ratio (KC) because their partition coefficient could not be equal to distribution ratio in common ionic conditions...
March 24, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28217983/extraction-and-separation-of-lactate-dehydrogenase-inhibitors-from-poria-cocos-schw-wolf-based-on-a-hyphenated-technique-and-in-vitro-methods
#10
Sainan Li, Jianxu Zhang, Senlin Li, Chunming Liu, Shu Liu, Zhiqiang Liu
Stroke is one of the most common diseases worldwide. Lactate dehydrogenase inhibitors are widely used in the treatment of ischemic stroke, with natural products considered a promising source of lactate dehydrogenase inhibitors. In this study, ultrafiltration liquid chromatography coupled with mass spectrometry was used for the screening and identification of lactate dehydrogenase inhibitors from Poria cocos. Five lactate dehydrogenase inhibitors were selected: dehydropachymic acid, pachymic acid, dehydrotrametenolic acid, trametenolic acid, and eburicoic acid...
April 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28215402/development-of-an-efficient-fractionation-method-for-the-preparative-separation-of-sesquiterpenoids-from-tussilago-farfara-by-counter-current-chromatography
#11
Kwangho Song, Kyoung Jin Lee, Yeong Shik Kim
A novel application of counter-current chromatography (CCC) to enrich plant extracts using direct and continuous injection (CCC-DCI) was developed to fractionate sesquiterpenoids from the buds of Tussilago farfara L. In this study, an n-hexane-acetonitrile-water (HAcW) solvent system was separately pumped into the CCC column, and an extraction solution (45% acetonitrile) was directly and continuously injected into the CCC column. Since the extraction solution was used as a mobile phase in this method, solvent consumption could be greatly reduced...
March 17, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28190594/separation-of-betacyanins-from-purple-flowers-of-gomphrena-globosa-l-by-ion-pair-high-speed-counter-current-chromatography
#12
Aneta Spórna-Kucab, Joanna Jagodzińska, Sławomir Wybraniec
Betacyanins, known as antioxidants and chemopreventive natural compounds with colourful properties, were extracted from purple flowers of Gomphrena globosa L. belonging to the Amaranthaceae family and separated for the first time by ion-pair high-speed counter-current chromatography (HSCCC). The pigments were detected by LC-DAD-ESI-MS/MS technique. Separation of betacyanins (300mg) by HSCCC was accomplished in four solvent systems: tert-butyl methyl ether - butanol - acetonitrile - water (0.7% and 1.0% HFBA - heptafluorobutyric acid - system I and III) and tert-butyl methyl ether - butanol - methanol - water (0...
March 17, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28164437/separation-of-six-xanthones-from-swertia-franchetiana-by-high-speed-counter-current-chromatography
#13
Hongmei Li, Tao Chen, Jing Sun, Weiqing Wang, Yulin Li
Two groups of xanthone isomers (1-hydroxy-3,5,8-trimethoxyxanthone and 1-hydroxy-3,7,8-trimethoxyxanthone, 1,8-dihydroxy-3,7-dimethoxyxanthone and 1,8-dihydroxy-3,5-dimethanolxanthone) and two other xanthones (3-methoxy-1,5,8-trihydroxyxanthone and 3,5-dimethoxy-1-hydroxyxanthone) were separated from Swertia franchetiana. First, a solvent system composed of petroleum ether/methanol/water (2:1:0.6, v/v) was developed for the liquid-liquid extraction of these xanthones from the crude extract. Then, an efficient method was established for one step separation of these six xanthones by high-speed counter-current chromatography using n-hexane/ethyl acetate/methanol/ethanol/water (6:4:4:2:4, v/v) as the solvent system...
February 6, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28157166/an-efficient-method-for-the-preparative-isolation-and-purification-of-flavonoid-glycosides-and-caffeoylquinic-acid-derivatives-from-leaves-of-lonicera-japonica-thunb-using-high-speed-counter-current-chromatography-hsccc-and-prep-hplc-guided-by-dpph-hplc-experiments
#14
Daijie Wang, Ning Du, Lei Wen, Heng Zhu, Feng Liu, Xiao Wang, Jinhua Du, Shengbo Li
In this work, the n-butanol extract from leaves of Lonicera japonica Thunb. (L. japonica) was reacted with DPPH and subjected to a HPLC analysis for the guided screening antioxidants (DPPH-HPLC experiments). Then, nine antioxidants, including flavonoid glycosides and caffeoylquinic acid derivatives, were isolated and purified from leaves of L. japonica using high speed counter-current chromatography (HSCCC) and prep-HPLC. The n-butanol extract was firstly isolated by HSCCC using methyl tert-butyl ether/n-butanol/acetonitrile/water (0...
February 2, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28121060/combined-application-of-chromatographic-techniques-for-the-separation-of-phenolic-compounds-from-stenoloma-chusanum-ching
#15
Dabing Ren, Binsong Han, Zhongquan Xin, Shasha Ma, Wenbin Liu, Lunzhao Yi
High-speed countercurrent chromatography combined with preparative high-performance liquid chromatography was successfully used to separate seven phenolic compounds from Stenoloma chusanum Ching. A biphasic solvent system composed of hexane/ethyl acetate/methanol/water (1:2:1:2, v/v) was used for the first step high-speed countercurrent chromatography separation in elution-extrusion mode. A mobile phase composed of acetonitrile (18%) and pure water (82%) was used for further preparative high-performance liquid chromatography purification...
January 25, 2017: Journal of Separation Science
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-countercurrent-chromatography-and-reversed-phase-flash-chromatography
#16
Junfei Tao, Rongwei Yan, Leilei Zhao, Dongmei Wang, Xinjun Xu
10-Deacetylbaccatin III, an important semisynthetic 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 countercurrent 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...
March 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28049583/purification-of-semiconducting-single-walled-carbon-nanotubes-by-spiral-counter-current-chromatography
#17
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...
February 3, 2017: 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
#18
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
#19
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
#20
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
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