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Counter current chromatography

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https://www.readbyqxmd.com/read/28783121/isolation-and-purification-of-three-ecdysteroids-from-the-stems-of-diploclisia-glaucescens-by-high-speed-countercurrent-chromatography-and-their-anti-inflammatory-activities-in-vitro
#1
Lei Fang, Jialian Li, Jie Zhou, Xiao Wang, Lanping Guo
High-speed counter-current chromatography was used to separate and purify ecdysteroids for the first time from the stems of Diploclisia glaucescens using a two-phase solvent system composed of ethyl acetate-n-butanol-ethanol-water (3:0.2:0.8:3, v/v). Three ecdysteroids were obtained from 260 mg of ethyl acetate extract of the residue obtained after evaporation of the crude ethanolicextractof D. glaucescens in one-step separation, which were identified as paristerone (I, 30.5 mg), ecdysterone (II, 7.2 mg), and capitasterone (III, 8...
August 7, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28758711/enantioseparation-of-pheniramine-enantiomers-by-high-speed-counter-current-chromatography-using-%C3%AE-cyclodextrin-derivatives-as-a-chiral-selector
#2
Weifeng Xu, Shichuan Wang, Xiaojuan Xie, Panliang Zhang, Kewen Tang
The enantioselective separation of pheniramine was studied by a high-speed counter-current chromatography method using β-cyclodextrin derivatives as a chiral selector. Several key variables, for instance, type of organic solvent and chiral selector, concentration of chiral selector, pH value of aqueous phase and temperature on the enantioselectivity, were investigated systematically by liquid-liquid extraction experiments. Combining the results of extraction experiments and high-speed counter-current chromatography, the most suitable conditions for separation of pheniramine enantiomers were obtained with the two-phase system that consisted of isobutyl acetate/aqueous phase, containing 0...
July 31, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28738554/amperometric-detector-for-gas-chromatography-based-on-a-silica-sol-gel-solid-electrolyte
#3
William H Steinecker, Krzysztof Miecznikowski, Pawel J Kulesza, Zechariah D Sandlin, James A Cox
An electrochemical cell comprising a silica sol-gel solid electrolyte, a working electrode that protrudes into a gas phase, and reference and counter electrodes that contact the solid electrolyte comprises an amperometric detector for gas chromatography. Under potentiostatic conditions, a current related to the concentration of an analyte in the gas phase is produced by its oxidation at the three-phase boundary among the sol-gel, working electrode, and the gas phase. The sol-gel is processed to contain an electrolyte that also serves as a humidistat to maintain a constant water activity even in the presence the gas chromatographic mobile phase...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28732888/separation-of-polysaccharides-from-spirulina-platensis-by-hsccc-with-ethanol-ammonium-sulfate-atps-and-their-antioxidant-activities
#4
Xueyan Wu, Ruichang Li, Yongjie Zhao, Yang Liu
Three separation methods for water-soluble polysaccharides from Spirulina platensis (PSP) were compared, including sevage deproteinization and column chromatography, ethanol-ammonium sulfate aqueous two-phase system (ATPS) and column chromatography, and one-step high speed counter-current chromatography (HSCCC) with ethanol-ammonium sulfate ATPS. ATPS was confirmed as an efficient alternative method of protein removal for PSP purification. For the HSCCC with ethanol-ammonium sulfate ATPS, the stationary retention reached to 50...
October 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28726768/characterization-and-purification-of-bergamottin-from-citrus-grandis-l-osbeck-cv-yongjiazaoxiangyou-and-its-antiproliferative-activity-and-effect-on-glucose-consumption-in-hepg2-cells
#5
Yilong Liu, Chuanhong Ren, Yunlin Cao, Yue Wang, Wenyi Duan, Linfeng Xie, Chongde Sun, Xian Li
Bergamottin is a natural furanocoumarin compound with weak polarity. Characterization and quantification of bergamottin were carried out in different fruit tissues of various citrus cultivars. Among the four citrus tissues tested, i.e., flavedo, albedo, segment membrane (SM), and juice sacs (JS) in eight citrus cultivars, the highest bergamottin content was found in the flavedo of Citrus grandis (L.) Osbeck cv. Yongjiazaoxiangyou (YJZXY, 666.54 μg·g(-1) DW). A combination of silica gel column chromatography and high-speed counter-current chromatography (HSCCC) was established to efficiently purify bergamottin from the flavedo of YJZXY...
July 20, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28698171/natural-compounds-for-the-treatment-of-psoriatic-arthritis-a-proposal-based-on-multi-targeted-osteoclastic-regulation-and-on-a-preclinical-study
#6
Shiqiang Deng, Jianwen Cheng, Jinmin Zhao, Felix Yao, Jiake Xu
BACKGROUND: Psoriatic arthritis (PsA) is a chronic inflammatory arthritis affecting approximately 2% to 3% of the population globally, and is characterized by both peripheral articular manifestations and axial skeletal involvement. Conventional therapies for PsA have not been fully satisfactory, though natural products (NPs) have been shown to be highly effective and represent important treatment options for psoriasis. PsA is a multigenic autoimmune disease with both environmental and genetic factors contributing to its pathogenesis...
July 11, 2017: JMIR Research Protocols
https://www.readbyqxmd.com/read/28688721/separation-and-preparation-of-xanthochymol-and-guttiferone-e-by-high-performance-liquid-chromatography-and-high-speed-counter-current-chromatography-combined-with-silver-nitrate-coordination-reaction
#7
Jun Li, Ruixi Gao, Dan Zhao, Xianju Huang, Yu Chen, Fei Gan, Hui Liu, Guangzhong Yang
Xanthochymol (XCM) and guttiferone E (GFE), a pair of π bond benzophenone isomers from Garcinia xanthochymus, were once reported to be difficult or impossible to separate. The present study reports the successful separation of these two isomers through high performance liquid chromatography (HPLC), as well as their effective isolation using high speed counter-current chromatography (HSCCC) based on the silver nitrate (AgNO3) coordination reaction. First, an effective HPLC separation system was developed, achieving a successful baseline separation with resolution of 2...
July 4, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28681407/large-scale-isolation-of-high-purity-anthocyanin-monomers-from-mulberry-fruits-by-combined-chromatographic-techniques
#8
Yao Chen, Fang Du, Wei Wang, Qian Li, Daheng Zheng, Weijie Zhang, Ting Zhao, Guanghua Mao, Weiwei Feng, Xiangyang Wu, Liuqing Yang
Anthocyanins have attracted attention over the past several decades because of their beneficial health effects. In this research, a strategy combining column chromatography and high-speed counter-current chromatography was developed for the separation of high-purity anthocyanin monomers from mulberry fruits. After purification using Amberlite XAD-7HP column with 80% ethanol (0.1% HCl), a fraction of anthocyanins mixtures with a purity of 68.6% was obtained. High-speed counter-current chromatography with a biphasic solvent system of n-butanol/methyl tert-butyl ether/acetonitrile/water/trifluoroacetic acid (30:10:10:50:0...
July 6, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28665764/determination-of-sudan-i-and-a-newly-synthesized-sudan-iii-positional-isomer-in-the-color-additive-d-c-red-no-17-using-high-performance-liquid-chromatography
#9
Adrian Weisz, India C James, Christian J Tae, Clark D Ridge, Yoichiro Ito
Specifications in the Code of Federal Regulations for the color additive D&C Red No. 17 (Colour Index 26100) limit the levels of two subsidiary colors, 1-(phenylazo)-2-naphthol (Sudan I) and 1-[[2-(phenylazo)phenyl]azo]-2-naphthalenol (Sudan III o-isomer), to 3% and 2%, respectively. The present work reports the development of a high-performance liquid chromatography (HPLC) method for the quantitative determination of these subsidiary colors. Since Sudan III o-isomer needed to be synthesized for use as a reference material, a two-step procedure was devised: (i) preparative-scale synthesis of the intermediate 2-aminoazobenzene (2AAB) and its purification by counter-current chromatography and (ii) diazotization of 2AAB and coupling with 2-naphthol...
June 30, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
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
#10
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
#11
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
#12
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
#13
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
#14
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...
July 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
#15
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
#16
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
#17
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
#18
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
#19
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
#20
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
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