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Isolation and purification of seven compounds from extract of Rheum Palmatum L. by high speed counter current chromatography and rapid preparative chromatography

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Abstract

High speed counter current chromatography (HSCCC) combined with rapid preparative chromatography (RPC) was developed for the separation and purification of seven compounds from Rheum palmatum L. in this paper. Compounds dimmer-catechin, catechin, trans-3,5,4′-trihydroxystilbene-4′-O-β-D-(6′-O-gallayl)-glucoside, 1-O-Galloyl-6-O-cinnamoyl-glucose, 1-O-Galloyl-2-O-cinnamoyl-glucose, rhein and emodin were isolated and purified by HSCCC using an optimized two-phase solvent system composed of n-hexane–ethyl acetate–n-butanol–water (1:2:1:4, v/v/v/v) and RPC. The purities of compounds 1, 3, 4 and 6 from HSCCC separation were over 98.70%, 96.75%, 98.20% and 98.07%, and those of compounds 1, 2, 4, 5 and 7 from RPC separation were 95.33%, 89.40%, 93.7%, 92.89% and 94.76%, determined by HPLC. The HSCCC and RPC fractions were analyzed by HPLC and electrospray ion source mass spectroscopy (ESI-MSn) in negative ion mode. The identification of the seven compounds from the extract of R. palmatum L. was based on matching their retention time, the detection of the molecular ions and the fragment ions of the molecular ion obtained in the MSn experiments with those of the data reported in the literature. The results demonstrated that HSCCC and RPC are feasible and efficient techniques for systematic isolation of bioactive components from R. palmatum L.

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... Besides, quercitrin had been uncovered to have bioactive such as antioxidant, anti-inflammation and enhance osteoblast [56]. It accumulated more in under canopy habitats, and had also been identified and quantified in seeds of Rh. palmatum [57]. However, lindleyin [58] and coumarin [59], which were accumulated higher at open habitats, had been identified from rhubarb and were demonstrated to beneficial for protect neuro and antioxidant or anti-inflammatory and have a few pharmacological effects [58,60,61]. ...
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A polymer monolithic column was prepared via redox system in a stainless steel column (50 × 4.6 mm i.d.) by using 1,6-hexanediol diacrylate as monomer and ethylene dimethacrylate as cross linking agent. Characteristics of the homemade monolithic column were investigated by scanning electron microscopy, nitrogen adsorption-desorption and mercury intrusion porosimeter, respectively. The results showed that the resulting monolithic column occupied relative uniform porous skeleton structure. Furthermore, the monolith was tested by separating aromatic compounds in conjunction of high performance liquid chromatography with the highest column efficiency of more than 21,000 plate per meter, which was relative high for polymer-based monolithic column with 4.6 mm i.d. At last, the monolithic column was used to simultaneously separate and quantitatively analyzes five active compounds in Chinese herb Rheum palmatum L. The validation of the method was carried out, which indicated that the accuracy represented by recovery was in the range of 98.48% to 101.57%. Limit of detection and limit of quantification for the five active compounds were less than 33.7 ng and 90.8 ng, respectively. All the results indicated that the present method was simple and efficient for quantitative analysis of the five active compounds from Chinese herb Rheum palmatum L. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 133, 44874.
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