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Details

Autor(en) / Beteiligte
Titel
Preparative isolation of huperzines A and B from Huperzia serrata by displacement centrifugal partition chromatography
Ist Teil von
  • Journal of Chromatography A, 2007-01, Vol.1140 (1), p.101-106
Ort / Verlag
Amsterdam: Elsevier B.V
Erscheinungsjahr
2007
Quelle
MEDLINE
Beschreibungen/Notizen
  • The pH-zone refining centrifugal partition chromatography technique was used to separate the two acetylcholinesterase inhibitors huperzines A and B from a crude alkaloid extract of the club moss Huperzia serrata. Complete co-elution of huperzines A and B was initially observed with the well-known methyl tert-butyl ether–acetonitrile–water (4:1:5, v/v/v) solvent system with triethylamine (8 mM) as the displacer and methane sulfonic acid (6 mM) as the retainer. An efficient biphasic system was designed on the basis of solvent association that provided selectivity in the elution mode: n-heptane/ethyl acetate/ n-propanol/water (5:15:35:45, v/v/v/v). Lowering the bridge solvent content ( n-propanol) of this system increased the polarity difference between the two phases thus adapting it to the pH-zone refining mode. Thus, the purification of these compounds was achieved using the biphasic system n-heptane/ethyl acetate/ n-propanol/water (10:30:15:45, v/v/v/v) with triethylamine (8 mM) as the displacer and methane sulfonic acid (6 mM) as the retainer.

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