%0 Journal Article
%T LC/MS Guided Isolation of Alkaloids from Lotus Leaves by pH-Zone-Refining Counter-Current Chromatography
%A Xia Xu
%A Cui-Rong Sun
%A Xiao-Jing Dai
%A Rui-Lin Hu
%A Yuan-Jiang Pan
%A Zhang-Fa Yang
%J Molecules
%D 2011
%I MDPI AG
%R 10.3390/molecules16032551
%X The traditional methods used in natural product separation primarily target the major components and the minor components may thus be lost during the separation procedure. Consequently, it¡¯s necessary to develop efficient methods for the preparative separation and purification of relatively minor bioactive components. In this paper, a LC/MS method was applied to guide the separation of crude extract of lotus (Nelumbo nucifera Gaertn.) leaves whereby a minor component was identified in the LC/MS analysis. Afterwards, an optimized pH-zone-refining CCC method was performed to isolate this product, identified as N-demethylarmepavine. The separation procedure was carried out with a biphasic solvent system composed of hexane-ethyl acetate-methyl alcohol-water (1:6:1:6, v/v) with triethylamine (10 mM) added to the upper organic phase as a retainer and hydrochloric acid (5 mM) to the aqueous mobile phase eluent. Two structurally similar compounds ¨C nuciferine and roemerine ¨C were also obtained from the crude lotus leaves extract. In total 500 mg of crude extract furnished 7.4 mg of N-demethylarmepavine, 45.3 mg of nuciferine and 26.6 mg of roemerine with purities of 90%, 92% and 96%, respectively. Their structures were further identified by HPLC/ESI-MSn, FTICR/MS and the comparison with reference compounds.
%K Nelumbo nucifera Gaertn.
%K alkaloids
%K minor component separation
%K pH-zone-refining counter-current chromatography
%U http://www.mdpi.com/1420-3049/16/3/2551