Preparative separation of alkaloids from Nelumbo nucifera leaves by conventional and pH-zone-refining counter-current chromatography
ABSTRACT Two modes of high-speed counter-current chromatography (HSCCC) were successfully applied to the separation of alkaloids from crude extract of Nelumbo nucifera leaves. The conventional HSCCC separations were performed with a two-phase solvent system composed of tetrachloromethane-CHCl3-methanol-0.1 M HCl at a volume ratio of 1:3:3:2 (v/v/v/v), and 120 mg crude extract could be successfully separated. pH-Zone-refining CCC was performed with a two-phase solvent system composed of petroleum ether (60-90 degrees C)-ethyl acetate-methanol-water (5:5:2:8, v/v/v/v) where triethylamine (10 mM) was added to the upper organic stationary phase as a retainer and hydrochloric acid (5 mM) to the aqueous mobile phase as an eluent. From 4.0 g of the crude extract, 120 mg N-nornuciferine, 1020 mg nuciferine and 96 mg roemerine were obtained in a single run each with a purity of over 98% as determined by HPLC. The structures of the isolated compounds were identified by ESI-MS, 1H NMR and 13C NMR.
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ABSTRACT: Procyanidins extracted with acetone-water from lotus (Nelumbo nucifera Gaertn.) seedpod (LSPCs) were evaluated for in vivo radioprotective activity against whole body gamma irradiation in Swiss albino mice. Pretreated with LSPCs 200 mg/kg by intragastric (i.g.) for 15 days was found to be the most effective dose in preventing radiation sickness, reducing radiation-induced mortality, increasing mean survival time and elevating radiation median lethal dose (LD(50)) from 8.9 to 10.5 Gy, indicating a dose modifying factor (DMF) of 1.18. Further, administered LSPCs at a dose of 200 mg/kg could effectively maintain spleen index close to normal, stimulate endogenous spleen colony forming units, promote the levels of red blood cells (RBC), white blood cells (WBC), platelets and hemoglobin in peripheral blood, and prevent spleen and skin damage in irradiated mice, reduce the level of radiation-induced micronucleated polychromatic erythrocytes in bone marrow, maintain the polychromatic erythrocytes (PCE) and normochromatic erythrocytes (NCE) ratio (P/N ratio) and significantly decrease bone marrow chromosomal damage. Alternatively, pretreated with LSPCs (200 mg/kg) significantly decreased the lipid peroxidation (LPO) level, and elevated the activities of endogenous antioxidant enzymes in liver after irradiation. Thus LSPCs possess a strong whole body radioprotective activity, and it may be used as a radioprotector.Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 12/2010; 48(12):3374-84. DOI:10.1016/j.fct.2010.09.008 · 2.90 Impact Factor
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ABSTRACT: Counter-current chromatography (CCC), a unique continuous liquid-liquid partition chromatographic technique, has been widely used in the separation and purification of natural products. This technique has made great progress in recent years. In this paper, the different possible separation methods developed in CCC are described. It includes classical CCC, pH-zone-refining, pH-gradient, ion-pairing, multi-channel and two-dimensional CCC, dual-flow, liquid-liquid-liquid three-phase systems, elution-extrusion, gradient elution, powder direct injection, with some words for the various techniques used in pre- and post-CCC procedures, and detection modes. The basic mechanisms of each method are presented and applications are summarized. The future of CCC developments, including its application in protein purification and enrichment, and new platforms, are also discussed. This review paper aims to aid scientists who are interested in the field of CCC research for natural product isolation.Separation and Purification Reviews 12/2010; 39(1-2):33-62. DOI:10.1080/15422119.2010.503690 · 2.82 Impact Factor