SHI Li-ying, CHEN Yao, LU Xuan, et al. New Enrichment Method and Characterization of Alkaloids in [J]. Chinese journal of experimental traditional medical formulae, 2018, 24(21): 56-61.
DOI:
SHI Li-ying, CHEN Yao, LU Xuan, et al. New Enrichment Method and Characterization of Alkaloids in [J]. Chinese journal of experimental traditional medical formulae, 2018, 24(21): 56-61. DOI: 10.13422/j.cnki.syfjx.20181615.
New Enrichment Method and Characterization of Alkaloids in
Objective: To investigate a new method for the enrichment of alkaloids
analyze the compositions of alkaloids
and look for new anti-asthmatic constituents in Ephedra sinica. Method: In order to reduce the interference by non-alkaloid components on qualitative analysis and to improve the efficiency of separation and preparation of alkaloids
alkaloids in E. sinica were enriched by using new solid phase extraction (SPE) packing in this study;and the fractions of the enriched alkaloids were prepared by applying high performance liquid chromatography (HPLC);HPLC-TOF-MS was used to identify the main components in each fraction;active constituents as β2-adrenergic receptor agonists were characterized by using label-free dynamic mass redistribution assays. Result: The results indicated that AC18 SPE packing had high selectivity for the enrichment of alkaloids in E. sinica. A mixed-mode chromatography method was developed to separate alkaloids based on a mixed-mode reversed phase/strong anion-exchange XCharge C18 column
and 14 fractions were prepared in total. In high performance liquid chromatography-mass spectrometry (HPLC-MS)
26 alkaloids were identified. Among the 14 fractions screened
11 fractions showed agonistic activity on β2-adrenergic receptor(β2-AR). Combined with HPLC-MS results for these 11 fractions
12 alkaloids displayed agonistic activity on β2-AR
including 5 groups of alkaloid and thier isomers:ephedrine/pseudoephedrine
methyl ephedrine/methyl pseudoephedrine
norephedrine/norpseudoephedrine (±) -1-phenyl-2-imido-1-propanol and (±) -tyramine betaine. Conclusion: The separation and characterization of alkaloid isomers in E. sinica provided guidance for discovering novel anti-asthmatic constituents.