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Counter current chromatography

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https://www.readbyqxmd.com/read/28938495/polyphenol-enriched-fractions-of-cyclopia-intermedia-selectively-affect-lipogenesis-and-lipolysis-in-3t3-l1-adipocytes
#1
Babalwa U Jack, Christiaan J Malherbe, Elize L Willenburg, Dalene de Beer, Barbara Huisamen, Elizabeth Joubert, Christo J F Muller, Johan Louw, Carmen Pheiffer
Cyclopia species are increasingly investigated as sources of phenolic compounds with potential as therapeutic agents. Recently, we demonstrated that a crude polyphenol-enriched organic fraction (CPEF) of Cyclopia intermedia, currently forming the bulk of commercial production, decreased lipid content in 3T3-L1 adipocytes and inhibited body weight gain in obese db/db mice. The aim of the present study was to determine whether a more effective product and/or one with higher specificity could be obtained by fractionation of the CPEF by purposely increasing xanthone and benzophenone levels...
September 22, 2017: Planta Medica
https://www.readbyqxmd.com/read/28892307/purification-of-polysaccharide-from-artificially-cultivated-anoectochilus-roxburghii-wall-lindl-by-high-speed-counter-current-chromatography-and-its-antitumor-activity
#2
Xiaoling Yu, Shouer Lin, Jinque Zhang, Liying Huang, Hong Yao, Shaoguang Li
To establish a systematic method for the extraction, purification, characterization and antitumor activity study of polysaccharide from artificially cultivated Anoectochilus roxburghii(wall.) Lindl. (AC-ARPS). High-speed counter current chromatography with two-phase aqueous systems was successfully applied to purify AC-ARPS after one-step separation. The purity of the AC-ARPS obtained by phenol/sulfuric acid method was 95.01%. The chemical structures of AC-ARPS were identified by a series analytical methods including high-performance liquid chromatography and liquid chromatography with mass spectrometry...
September 11, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28857450/screening-separation-and-evaluation-of-xanthine-oxidase-inhibitors-from-paeonia-lactiflora-using-chromatography-combined-with-a-multi-mode-microplate-reader
#3
Jing Wang, Dongfang Shi, Meizhu Zheng, Bing Ma, Jing Cui, Chunming Liu, Chengyu Liu
Natural products have become one of the most important resources for discovering novel xanthine oxidase inhibitors, which are commonly employed in the treatment of hyperuricemia and gout. However, to date, few reports exist regarding the use of monoterpene glycosides as xanthine oxidase inhibitors. Thus, we herein report the use of ultrafiltration coupled with liquid chromatography in the screening of monoterpene glycoside xanthine oxidase inhibitors from the extract of Paeonia lactiflora (P. lactiflora), and both high-performance counter-current chromatography and medium-pressure liquid chromatography were employed to separate the main constituents...
August 30, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28826244/isolation-and-structure-determination-of-a-new-flavone-glycoside-from-seed-residues-of-seabuckthorn-hippophae-rhamnoides-l
#4
Wenna Zhou, Zhenzhen Yuan, Gang Li, Jian Ouyang, Yourui Suo, Honglun Wang
In this study, a valid method was established for the isolation and purification of flavone glycosides from Hippophae rhamnoides L. seed residues using high-speed counter-current chromatography in one step, with a solvent system of ethyl acetate-methanol-n-butyl alcohol-water (9:1:0.5:9, v/v/v/v). A total of 28.8 mg compound I and 57.3 mg compound II were obtained from 200 mg of flavone H-glycosides rich extract, with purities of 98.3 and 96.4%, respectively. The structures of two compounds were identified by MS and NMR...
August 22, 2017: Natural Product Research
https://www.readbyqxmd.com/read/28816397/a-flow-through-column-electrolytic-cell-for-supercritical-fluid-chromatography
#5
Kazuhiro Yamamoto, Tatsuya Ueki, Naoyuki Higuchi, Kouji Takahashi, Akira Kotani, Hideki Hakamata
A novel flow-through column electrolytic cell was proposed as a detector to obtain current signals for supercritical fluid chromatography. The electrochemical cell consisted of two electrodes and its holder, and a working and a counter electrode were fabricated from 192 carbon strings, which were composed of 400 carbon fibers of 10 μm in diameter filled into a heat-shrinkable tube. These electrodes were placed in the center of a holder made from polyether ether ketone blocks and they were separated by polytetrafluoroethylene membrane filters...
August 17, 2017: Journal of Separation Science
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
#6
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
#7
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
#8
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
#9
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
#10
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
#11
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
#12
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
#13
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 countercurrent 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 countercurrent chromatography with a biphasic solvent system of n-butanol/methyl tert-butyl ether/acetonitrile/water/trifluoroacetic acid (30:10:10:50:0...
September 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
#14
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
#15
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
#16
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
#17
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
#18
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
#19
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
#20
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
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