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Counter current chromatography

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https://www.readbyqxmd.com/read/29150928/application-of-high-speed-counter-current-chromatography-and-hplc-to-separate-and-purify-of-three-polyacetylenes-from-platycodon-grandiflorum
#1
Bao Chen, Zhengbo Liu, Yuwei Zhang, Wei Li, Yanjun Sun, Yufang Wang, Yanhua Wang, Yinshi Sun
Three polyacetylenes were isolated and purified from Platycodon grandiflorum A. DC for the first time by high-speed counter-current chromatography using a two-phase solvent system composed of hexane/ethyl acetate/methanol/water (1:31:1:31, v/v/v/v) and high-performance liquid chromatography with an Agilent ZORBAX(®) SB-C18 column (4.6 mm × 150 mm, 5 μm). After separation by high-speed counter-current chromatography and high-performance liquid chromatography, we obtained 3.5 mg of platetyolin A, 4.1 mg of platetyolin B, and 18...
November 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/29149084/preparative-separation-and-purification-of-four-glycosides-from-gentianae-radix-by-high-speed-counter-current-chromatography-and-comparison-of-their-anti-no-production-effects
#2
Bao Chen, Yinghua Peng, Xinhui Wang, Zhiman Li, Yinshi Sun
Secoiridoid and iridoid glycosides are the main active components of Gentianaeradix. In this work, one iridoid and three secoiridoid glycosides from Gentianaeradix have been purified by high-speed counter-current chromatography in two runs using different solvent systems. Ethyl acetate-n-butanol-water (2:1:3, v/v/v) was the optimum solvent system to purify ca. 4.36 mg of loganic acid, 3.05 mg of swertiamarin, and 35.66 mg of gentiopicroside with 98.1%, 97.2% and 98.6% purities, respectively, while 31.15 mg of trifloroside with 98...
November 17, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29136554/separation-and-purification-of-four-phenolic-compounds-from-persimmon-by-high-speed-counter-current-chromatography
#3
Jinming Peng, Kaikai Li, Wei Zhu, Xiangyi Deng, Chunmei Li
An efficient method was established by high-speed counter-current chromatography (HSCCC) for preparation of four phenolic compounds from the depolymerization products of persimmon tannin. Using the two solvent systems of n-hexane/ethyl acetate/water (3:17:20, v/v/v) and ethyl acetate/methanol/water (50:1:50, v/v/v), the preparative isolation was successfully performed by a two-step separation. The yields of one run (150mg crude sample) for gallic acid, methyl gallate, and epigallocatechin-3-gallate-(4β→8, 2β→O→7)-epigallocatechin-3-gallate dimer (A-type EGCG dimer) were 4...
November 7, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29078985/definition-and-dynamic-control-of-a-continuous-chromatography-process-independent-of-cell-culture-titer-and-impurities
#4
Rebecca A Chmielowski, Linda Mathiasson, Hans Blom, Daniel Go, Hanno Ehring, Heera Khan, Hong Li, Collette Cutler, Karol Lacki, Nihal Tugcu, David Roush
Advances in cell culture technology have enabled the production of antibody titers upwards of 30g/L. These highly productive cell culture systems can potentially lead to productivity bottlenecks in downstream purification due to lower column loadings, especially in the primary capture chromatography step. Alternative chromatography solutions to help remedy this bottleneck include the utilization of continuous processing systems such as periodic counter-current chromatography (PCC). Recent studies have provided methods to optimize and improve the design of PCC for cell culture titers up to about 3g/L...
December 1, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/29071789/online-hyphenation-of-extraction-sephadex-lh-20-column-chromatography-and-high-speed-counter-current-chromatography-a-highly-efficient-strategy-for-the-preparative-separation-of-andrographolide-from-andrographis-paniculata-in-a-single-step
#5
Ying-Qi Zhang, Shan-Shan Wang, Chao Han, Jin-Fang Xu, Jian-Guang Luo, Ling-Yi Kong
A novel isolation strategy, on-line hyphenation of ultrasonic extraction, Sephadex LH-20 column chromatography combined with high-speed counter-current chromatography, was developed for pure compounds extraction and purification. Andrographolide from Andrographis paniculata was achieved only in a single step purification protocol via the present strategy. The crude powder was ultrasonic extracted and extraction was pumped into Sephadex LH-20 column directly to cut the non-target fractions followed by the second dimensional high-speed counter-current chromatography, hyphenated by a six-port valve equipped at the post-end of Sephadex LH-20 column, for the final purification...
October 26, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/29064630/screening-and-separation-of-%C3%AE-amylase-inhibitors-from-solanum-nigrum-with-amylase-functionalized-magnetic-graphene-oxide-combined-with-high-speed-counter-current-chromatography
#6
Yin Cen, Aiping Xiao, Xiaoqing Chen, Liangliang Liu
A screening method using α-amylase-functionalized magnetic graphene oxide combined with high-speed counter-current chromatography was proposed and utilized to screen and separate α-amylase inhibitors from extract of Solanum nigrum. The α-amylase-functionalized magnetic graphene oxide was characterized and found to demonstrate satisfactory structure, magnetic response (24.5 emu/g) and reusability (retained 90% of initial activity after five cycles). The conditions for the screening with α-amylase functionalized magnetic graphene oxide were optimized and set at pH 7...
October 24, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/29045617/purification-of-four-flavonoid-glycosides-from-lotus-nelumbo-nucifera-gaertn-plumule-by-macroporous-resin-combined-with-hsccc
#7
Lei Wu, Wei Xiong, Ju-Wu Hu, Zhen Gu, Jian-Guo Xu, Chuan-Ling Si, Young-Soo Bae, Gang Xu
High-speed counter-current chromatography (HSCCC) combined with macroporous resin (MR) column was successfully applied to the isolation and purification of four flavonoid glycosides from the medicinal herb Lotus plumule (LP). A polar two-phase solvent system composed of ethyl acetate-n-butanol-water (1:2:3, v/v/v) was selected by high-performance liquid chromatography (HPLC) and run on a preparative scale where the lower aqueous phase was used as the mobile phase with a head-to-tail elution mode. Quercetin-3-O-β-D-glucopyranoside (15 mg), isorhamnetin-3-O-β-D-glucopyranoside (13 mg), apigenin 6-C-β-D-glucopyranosyl-8-C-α-L-arabinopyranoside (18 mg) and apigenin 6,8-di-C-β-D-glucopyranoside (48 mg) were obtained in a one-step HSCCC separation from 240 mg of the sample...
October 17, 2017: Journal of Chromatographic Science
https://www.readbyqxmd.com/read/28977348/isolation-of-flavonoids-from-wild-aquilaria-sinensis-leaves-by-an-improved-preparative-high-speed-counter-current-chromatography-apparatus
#8
Mao-Xun Yang, Yao-Guang Liang, He-Ru Chen, Yong-Fang Huang, Hai-Guang Gong, Tian-You Zhang, Yoichiro Ito
Four flavonoids including apigenin-7,4'-dimethylether, genkwanin, quercetin, and kaempferol were isolated in a preparative or semi-preparative scale from the leaves of wild Aquilaria sinensis using an improved preparative high-speed counter-current chromatography apparatus. The separations were performed with a two-phase solvent system composed of hexane-ethyl acetate, methanol-water at suitable volume ratios. The obtained fractions were analyzed by HPLC, and the identification of each target compound was carried out by ESI-MS and NMR...
September 5, 2017: Journal of Chromatographic Science
https://www.readbyqxmd.com/read/28968588/determination-of-specific-alpha-emitting-radionuclides-uranium-plutonium-thorium-and-polonium-in-water-using-ba-fe-coprecipitation-method
#9
J A Suarez-Navarro, Ll Pujol, M J Suarez-Navarro
The indicative dose (ID) is one of the parameters established in the current European directive for water intended for human consumption. To determine the ID, it is necessary to know the activity concentration of: (238)U, (234)U, (226)Ra, (210)Po, (239,240)Pu and (241)Am. The existing methods to determine these radionuclides involve complex radiochemical separations (ionic exchange columns, extraction chromatography, etc.), followed by measurements with a semiconductor detector, laboratory procedures that are time-consuming and costly...
September 23, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/28958734/characterization-of-diarylheptanoids-an-emerging-class-of-bioactive-natural-products
#10
REVIEW
Ágnes Alberti, Eszter Riethmüller, Szabolcs Béni
Diarylheptanoids are a class of secondary plant metabolites with a wide variety of bioactivity. Research on their phytochemistry and phytoanalysis is rapidly growing and the number of identified structures bearing the aryl-C7-aryl skeleton is at present approaching 500. Historically, the yellow pigment curcumin has been characterized as the first diarylheptanoid and the extensive research on naturally occurring analogues is still ongoing. In this review, studies dealing with the characterization of linear and cyclic derivatives are discussed from the phytoanalytical point of view...
September 21, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28958733/identification-of-bacillus-thuringiensis-cry1abmod-binding-proteins-from-spodoptera-frugiperda
#11
Diana L Martínez de Castro, Blanca I García-Gómez, Isabel Gómez, Alejandra Bravo, Mario Soberón
Bacillus thuringiensis Cry toxins are currently used for pest control in transgenic crops but evolution of resistance by the insect pests threatens the use of this technology. The Cry1AbMod toxin was engineered to lack the alpha helix-1 of the parental Cry1Ab toxin and was shown to counter resistance to Cry1Ab and Cry1Ac toxins in different insect species including the fall armyworm Spodoptera frugiperda. In addition, Cry1AbMod showed enhanced toxicity to Cry1Ab-susceptible S. frugiperda populations. To gain insights into the mechanisms of this Cry1AbMod-enhanced toxicity, we isolated the Cry1AbMod toxin binding proteins from S...
September 25, 2017: Peptides
https://www.readbyqxmd.com/read/28939231/counter-current-chromatography-with-off-line-detection-by-ultra-high-performance-liquid-chromatography-high-resolution-mass-spectrometry-in-the-study-of-the-phenolic-profile-of-lippia-origanoides
#12
Suzana Guimaraes Leitão, Gilda Guimarães Leitão, Douglas K T Vicco, João Paulo Barreto Pereira, Gustavo de Morais Simão, Danilo R Oliveira, Rita Celano, Luca Campone, Anna Lisa Piccinelli, Luca Rastrelli
Lippia origanoides (Verbenaceae) is an important Brazilian medicinal plant, also used for culinary purposes. Most chemical studies with this plant have been focused on its volatile composition. In this work, we combined High-Speed Counter-current Chromatography (HSCCC) and High Performance Liquid Chromatography coupled to Ultra Violet detection and High Resolution Mass Spectrometry (HPLC-UV-HRMS(n)) methodologies to access the non-volatile chemical composition of L. origanoides. The crude ethanol extract of L...
September 6, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28938495/polyphenol-enriched-fractions-of-cyclopia-intermedia-selectively-affect-lipogenesis-and-lipolysis-in-3t3-l1-adipocytes
#13
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
#14
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 of 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
#15
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
#16
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
#17
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...
October 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
#18
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-countercurrent-chromatography-using-%C3%AE-cyclodextrin-derivatives-as-a-chiral-selector
#19
Weifeng Xu, Shichuan Wang, Xiaojuan Xie, Panliang Zhang, Kewen Tang
The enantioselective separation of pheniramine was studied by a high-speed countercurrent 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 countercurrent 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
#20
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
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