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Counter current chromatography

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https://www.readbyqxmd.com/read/28619589/isolation-of-sutherlandins-a-b-c-and-d-from-sutherlandia-frutescens-l-r-br-by-counter-current-chromatography-using-spiral-tubing-support-rotors
#1
Cuiping Chen, William R Folk, Rodrigo Lazo-Portugal, Thomas M Finn, Martha Knight
Spiral countercurrent-chromatography has great potential for improving the capacity and efficiency of purification of secondary metabolites, and here we describe applications useful for the isolation of flavonoids from the widely used South African medicinal plant, Sutherlandia frutescens (L.) R. Br. In the spiral tubing support rotor, STS-4 for high-speed counter-current chromatography, several polar butanol aqueous solvent systems were selected using a logK plot, and the novel flavonol glycosides (sutherlandins A-D) were well separated by the optimized solvent system (ethyl acetate:n-butanol:acetic acid:water; 5:1:0...
July 28, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28589595/high-speed-counter-current-chromatography-with-an-online-storage-technique-for-the-preparative-isolation-and-purification-of-dihydroflavonoids-from-sophora-alopecuroides-l
#2
Zhong-Lin Sun, Jian-Ming He, Jiang-Er Lan, Qing Mu
INTRODUCTION: High-speed counter-current chromatography (HSCCC) is an efficient and non-absorption separation technique, but limitations still exist in simultaneous isolation of complex structures of natural products. Moreover, particular methods are various for different kinds of natural products. OBJECTIVE: A novel HSCCC strategy combined with an online storage recycling elution (OSR-CCC) technique was developed for the quick separation of naturally occurring dihydroflavonoids from the extract of the herb Sophora alopecuroides L...
June 6, 2017: Phytochemical Analysis: PCA
https://www.readbyqxmd.com/read/28583393/separation-of-the-potential-g-quadruplex-ligands-from-the-butanol-extract-of-zanthoxylum-ailanthoides-sieb-zucc-by-countercurrent-chromatography-and-preparative-high-performance-liquid-chromatography
#3
Tian Han, Xueli Cao, Jing Xu, Hairun Pei, Hong Zhang, Yalin Tang
G-quadruplex DNA structure is considered to be a very attractive target for antitumor drug design due to its unique role in maintaining telomerase activities. Therefore, discovering ligands with high stability of G-quadruplex structure is of great interest. In this paper, pH-zone refining counter current chromatography (CCC) and preparative high performance liquid chromatography (HPLC) were employed for the separation of potent G-quadruplex ligands from the n-butanol fraction of the crude extract of Zanthoxylum ailanthoides, which is a traditional Chinese medicine recently found to display high inhibitory activity against several human cancer cells...
July 21, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28554864/theoretical-study-of-separation-and-concentration-of-solutes-by-closed-loop-recycling-liquid-liquid-chromatography-with-multiple-sample-injection
#4
Artak E Kostanyan
The method of closed-loop recycling counter-current chromatography (CLR CCC) with multiple sample injection is proposed for the separation and concentration of a target component of a mixture. Analytical expressions are developed to describe the CLR CCC separations with multiple sample injection. Several possible implementations of multiple feed injection are analyzed: the feed is injected in each cycle, after every two cycles and in an arbitrary cycle. The application of different modes of multiple feed injection to the separation and concentration of the target component from binary mixtures by CLR CCC has been studied...
May 21, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28544633/extraction-and-purification-of-five-terpenoids-from-olibanum-by-ultrahigh-pressure-technique-and-high-speed-countercurrent-chromatography
#5
Jinqian Yu, Hongwei Zhao, Daijie Wang, Xiangyun Song, Lei Zhao, Xiao Wang
Five terpenoids, including two new ones, 3,7-dioxo-tirucalla-8,24-dien-21-oic acid (2) and 3α-acetoxyl-7-oxo-tirucalla-8,24-dien-21-oic acid (3), and three known ones, boscartol A (1), 11-keto-β-boswellic acid (4), and acetyl-11-keto-boswellic acid (5), have been extracted by the ultrapressure extraction and purified by pH-zone-refining countercurrent chromatography and high-speed countercurrent chromatography from olibanum. For ultrapressure extraction, the optimal condition including 200 MPa of extraction pressure, ethyl acetate of extraction solvent, 1:20 (g/mL) of solid/liquid ratio, and 2 min of extraction time were obtained...
May 22, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28528251/biological-activity-and-safety-profile-of-the-essential-oil-from-fruits-of-heracleum-mantegazzianum-sommier-levier-apiaceae
#6
Krystyna Skalicka-Woźniak, Agnieszka Grzegorczyk, Łukasz Świątek, Magdalena Walasek, Jarosław Widelski, Barbara Rajtar, Małgorzata Polz-Dacewicz, Anna Malm, Hosam O Elansary
A composition of essential oils obtained from Heracleum mantegazzianum (Apiaceae) was examined using a GC-MS method. n-Octyl acetate (19.92%), n-hexyl-2-methylbutanoate (10.84%), n-octanol (10.13%), n-octyl butanoate (8.88%), n-octyl-2-methylbutanoate (8.01%), n-hexyl acetate (7.11%), n-octyl isobutanoate (5.5%) and n-hexyl isobutanoate (5.43%) were the main compounds. The high-performance counter-current chromatography was applied for purification of aliphatic alcohols and esters. A mixture of n-hexane, acetonitrile and tetr-butyl methyl ether (1:1:0...
May 17, 2017: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/28513110/separation-and-purification-of-two-minor-typical-diarrhetic-shellfish-poisoning-toxins-from-harmful-marine-microalgae-via-combined-liquid-chromatography-with-mass-spectrometric-detection
#7
Junhui Chen, Yanlong Wang, Lei Pan, Huihui Shen, Dan Fu, Boqiang Fu, Chengjun Sun, Li Zheng
A novel method was developed for the purification of two typical diarrhetic shellfish poisoning toxins from toxin-producing marine microalgae using macroporous resin, high-speed countercurrent chromatography-mass spectrometry, and semipreparative high-performance liquid chromatography-mass spectrometry. Analytical high-performance liquid chromatography-mass spectrometry was used for identification and purity analysis of okadaic acid and dinophysistoxin-1 because they exhibit no visible or ultraviolet absorption...
May 17, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28459519/diterpenoid-tanshinones-the-extract-from-danshen-radix-salviae-miltiorrhizae-induced-apoptosis-in-nine-human-cancer-cell-lines
#8
Li Shen, Zhaohuan Lou, Guangshun Zhang, Guanhua Xu, Guangji Zhang
OBJECTIVE: To identify the active anti-tumor constituents in the extract from Danshen (Radix Salviae Miltiorrhizae) and investigate the mechanisms underlying the actions. METHODS: First, we introduced a two-step counter- current chromatography to extract the therapeutically active diterpenoid, tanshinone from Danshen (Radix Salviae Miltiorrhizae). The cholecystokinin (CCK-8) method was used to evaluate the inhibitory effect of diterpenoid tanshinone in liver cancer QGY-7703, lung cancer PC9, lung cancer A549, gastric cancer MKN-45, gastric cancer HGC-27, colon cancer HCT116, myeloma cellU266/ RPMI8226, and human breast cancer MCF-7 in vitro...
August 2016: Journal of Traditional Chinese Medicine, Chung i Tsa Chih Ying Wen Pan
https://www.readbyqxmd.com/read/28441546/isolation-of-new-polyacetylenes-from-the-roots-of-eurycoma-longifolia-via-high-speed-counter-current-chromatography
#9
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...
June 15, 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
#10
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
#11
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...
June 1, 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
#12
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...
May 15, 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
#13
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/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
#14
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
#15
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
#16
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
#17
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
#18
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
#19
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
#20
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
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