Results 121 to 130 of about 951 (168)

Concentration of Heavy Metals by High-Speed Countercurrent Chromatography

Journal of Liquid Chromatography & Related Technologies, 1998
Application of high-speed countercurrent chromatography (HSCCC) to the concentration of metal ions has been studied. The stationary phase, containing di(2-ethylhexyl) phosphoric acid (DEHPA) in n-heptane, was continuously fed into the column. The ppb level of metal ions in a 500 mL of the mobile phase was continuously concentrated into small volumes of
E. Kitazume, N. Sato, Y. Ito
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Separation of heavy metals by high-speed countercurrent chromatography

Analytical Chemistry, 1993
Separation of heavy metal elements such as Co, Cu, Fe(II),Fe(III), Mg, and Ni was performed with a high-speed CCC coil planet centrifuge equipped with a multilayer coil. The two-phase solvent systems used for the separation were composed of n-heptane containing bis(2-ethylhexyl) phosphoric acid (stationary phase) and diluted citric acid (mobile phase),
Eiichi. Kitazume, Nobuyoshi. Sato, Yoshihiro. Saito, Yoichiro. Ito   +3 more
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Preparative Separation of Polyphenols from Tea by High-Speed Countercurrent Chromatography

Journal of Agricultural and Food Chemistry, 2000
High-speed countercurrent chromatography (HSCCC) was applied to the separation of polyphenols from tea leaves (Camellia sinensis L.). The capability of HSCCC to isolate pure tea polyphenols from complex mixtures on a preparative scale was demonstrated for catechins, flavonol glycosides, proanthocyanidins, and strictinin from green and black tea.
A, Degenhardt, U H, Engelhardt, C, Lakenbrink, P, Winterhalter   +3 more
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Preparative isolation and purification of theaflavins and catechins by high-speed countercurrent chromatography

Journal of Chromatography B, 2008
High-speed countercurrent chromatography (HSCCC) has been applied for the separation of theaflavins and catechins. The HSCCC run was carried out with a two-phase solvent system composed of hexane-ethyl acetate-methanol-water-acetic acid (1:5:1:5:0.25, v/v) by eluting the lower aqueous phase at 2 ml/min at 700 rpm.
Kunbo, Wang, Zhonghua, Liu, Jian-an, Huang, Xinrong, Dong, Lubing, Song, Yu, Pan, Fang, liu   +6 more
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Isolation of Achyrobichalcone from Achyrocline satureioides by High- Speed Countercurrent Chromatography

Current Pharmaceutical Biotechnology, 2015
Achyrobichalcone is a biflavonoid recently found in Achyrocline satureioides. This substance has unprecedented chemical structure and occurrence, but resembles other bioactive bichalcones, which have important pharmacological properties, such as anticancer activity.
Juliana P, Carini, Gilda G, Leitão, Paulo H, Schneider, Cristiane C, Santos, Fernanda N, Costa, Maribete H, Holzschuh, Fábio, Klamt, Valquiria L, Bassani   +7 more
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Characterization of Pigments from Different High Speed Countercurrent Chromatography Wine Fractions

Journal of Agricultural and Food Chemistry, 2005
A red wine, made from Cabernet Sauvignon (60%) and Tannat (40%) cultivars, was fractionated by high speed countercurrent chromatography (HSCCC). The biphasic solvent system consisting of tert-butyl methyl ether/n-butanol/acetonitrile/water (2/2/1/5, acidified with 0.1% trifluoroacetic acid) was chosen for its demonstrated efficiency in separating ...
Salas, Erika, Dueñas, Montserrat, Schwarz, Michael, Winterhalter, Peter, Cheynier, Veronique, Fulcrand, Hélène   +5 more
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Recycling High-Speed Countercurrent Chromatography for Separation of Taxol and Cephalomannine

Journal of Liquid Chromatography & Related Technologies, 1998
Abstract A mixture of taxol and cephalomannine was subjected to recycling countercurrent chromatography (CCC) which allows the use of the same column for repetitive separation of the peak fractions to improve the peak resolution. When the total amount of 50 mg of the two components was recycled twice, peak resolution (Rs) increased from 0.7 to 1.27 ...
Q.-Z. Du, C.-Q. Ke, Y. Ito
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Separation of Lanthanides by High-Speed Countercurrent Chromatography with Organophosphate Ester

Journal of Liquid Chromatography & Related Technologies, 1996
Abstract High-speed countercurrent chromatography is a recently developed separation method that has been remarkably improved in both separating efficiency and separation time. In this paper, this advanced countercurrent chromatographic method was applied to the separation of lanthanides. In combination with the measurement of the partition coefficient
Zhongming Ma, Xiaoxiang Zheng
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Preparation and Purification of Epigallocatechin by High‐Speed Countercurrent Chromatography (HSCCC)

Journal of Liquid Chromatography & Related Technologies, 2004
Abstract Epigallocatechin (EGC) was prepared by the degallation of Epigallocatechin‐O‐3‐gallate (EGCG). EGCG was completely converted to EGC and gallic acid by adding 4 mg tannase/100 mg EGCG at the concentration of 2 mg/mL under pH 6.0, at 35°C for 30 min.
Xueli Cao, Yoichiro Ito
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HIGH-SPEED COUNTERCURRENT CHROMATOGRAPHY USING A SMALL COILED COLUMN

Journal of Liquid Chromatography & Related Technologies, 2000
Separation of selected lanthanoid elements was performed by high-speed countercurrent chromatography (CCC) equipped with a small coiled column of a 10 cm3 capacity. A hexane solution of 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (EHPA) was retained in the tubing column as the stationary phase.
Akira Tsuyoshi, Hiroaki Ogawa, Kenichi Akiba, Harutaka Hoshi, Eiichi Kitazume   +4 more
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