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Centrifugal Partition Chromatography (centrifugal + partition_chromatography)
Selected AbstractsMass transport and flow regimes in centrifugal partition chromatographyAICHE JOURNAL, Issue 8 2002L. Marchal Centrifugal partition chromatography (CPC) is a support-free liquid,liquid separation process that depends for efficiency on the behavior of the two liquid phases. Hydrodynamics of phases was studied according to flow rate and centrifugal acceleration, using a transparent column and a stroboscopic video system. For the heptane-methanol two-phase system, three main flow regimes,stuck film, oscillating sheet, and atomization,are observed, highlighting the coriolis acceleration effect as well as the influence of the column shape. Mass transport in the CPC column is modeled by a plug flow with axial dispersion and mass transfer with a stagnant volume. Model parameters (residence time, Péclet number, partition ratio, and mass-transfer coefficient) are fitted on solute residence-time distribution. Off-column dispersion is an important source of peak broadening in CPC, whereas its irregular geometry provides a plug flow for mobile phase. Importance of flow pattern on mass transfer is demonstrated. CPC interest for preparative applications is confirmed. [source] Preparative isolation and purification of six volatile compounds from essential oil of Curcuma wenyujin using high-performance centrifugal partition chromatographyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 11 2010Yuan-Ye Dang Abstract Six volatile compounds, curdione (1), curcumol (2), germacrone (3), curzerene (4), 1,8-cineole (5) and ,-elemene (6), were successfully isolated from the essential oil of Curcuma wenyujin by high-performance centrifugal partition chromatography using a nonaqueous two-phase solvent system consisting of petroleum ether-acetonitrile-acetone (4:3:1,v/v/v). A total of 8,mg of curdione (1), 4,mg of curcumol (2), 10,mg of germacrone (3), 18,mg of curzerene (4), 9,mg of 1,8-cineole (5) and 17,mg of ,-elemene (6) were isolated from the essential oil (300,mg) in 500,min. Their structures were determined by comparison of their retention times and MS data with those of the authentic samples as well as NMR spectroscopic analysis. [source] pH-Zone-refining centrifugal partition chromatography for preparative isolation and purification of steroidal glycoalkaloids from Solanum xanthocarpumJOURNAL OF SEPARATION SCIENCE, JSS, Issue 18 2009Anupam Maurya Abstract pH-Zone-refining centrifugal-partition chromatography (CPC) was successfully applied in the separation of complex polar steroidal glycoalkaloids of close Rf values, directly from a crude extract of Solanum xanthocarpum. The experiment was performed with a two phase solvent system composed of ethyl acetate/butanol/water (1:4:5 by volume) where triethylamine (5 mM) was added to the upper organic mobile phase as an eluter and TFA (10 mM) to the aqueous stationary phase as a retainer. Separation of 1 g of crude extract over CPC resulted in two distinct pH-zones. The fractions collected in pH-zone i afforded 72 mg of solasonine while the fractions collected in pH-zone ii were slightly impure, hence were purified over medium pressure LC, which afforded 30 mg of solasonine and further 15 mg of solamargine (SM). The steroidal glycoalkaloids, SM and solasonine were isolated in 93.3 and 91.6% purity, respectively. The isolated alkaloids were characterized on the basis of their 1H, 13C-NMR, and ESI-MS data. [source] Preparative separation of the saponin lancemaside a from Codonopsis lanceolata by centrifugal partition chromatographyPHYTOCHEMICAL ANALYSIS, Issue 5 2008Osamu Shirota Abstract Introduction. Lancemaside A is a saponin that inhibits decreases in blood testosterone level and thus prevents or ameliorates symptoms associated with male climacteric disorder. Our initial attempt to preparative isolation of lancemaside A from the saponin fraction of Codonopsis lanceolata roots by a preparative HPLC did not give a clear result. Objective. To develop a simple and efficient method for the preparative isolation of lancemaside A from the hot water extract of C. lanceolata roots using centrifugal partition chromatography (CPC). Methodology. The saponin fraction obtained from the hot water extract of C. lanceolata roots was used as the sample for preparative-scale separation of lancemasides by CPC using n -hexane:n -butanol:methanol:0.1% aqueous formic acid (3:4:1:6, v/v) as the two-phase solvent system. The upper phase (organic phase) of the two-phase solvent system was used as the mobile phase, and 0.5 g of saponin fraction was applied for separation by CPC. Each fraction that was separated by CPC was analysed by HPLC, and the fractions containing each of the separated compounds were pooled together, and then were purified by simple preparative HPLC. Results. The demonstrated separation sequence, hot water extraction, DIAION HP-20 column chromatography, CPC and preparative HPLC, yielded lancemaside A, foetidissimoside A and astersaponin Hb in their pure forms. Conclusion. The simple and efficient method for the preparative isolation of lancemaside A along with two other saponins, foetidissimoside A and astersaponin Hb, from the saponin fraction of C. lanceolata was established using CPC. [source] | ||||||||||