An effective method for isolation of the major components of ginseng saponin such as ginseroside-Rb₁, -Rb₂, -Rc, -Rd, -Re and -Rg₁, and the minor components such as ginsenoside-Rf, -Rg₂ and -Rh₁ was developed and reported in previous papers (J. Korean Agr. Chem. Soc., 23(4), 199 and 206(1980) The conditions and procedures used for isolation and identification for ginsenosides described in the previous papers were not sufficient enough for clean separation of minor components, ginsenoside-Rh₁ and -Rh₂.
In this work, modifications in extraction method and in mobile phase for HPLC were attempted. It was found that application of ethyl acetate extraction at 60℃ for 3 hr on crude saponin resulted in a removal of diol group saponin from crude saponin which made it possible for using higher portion of acetonitrile in mobile phase. The mixed solvents of acetonitrile : water (92 : 8 and 94 : 6) gave excellent resolution of ginsenoside-Rh₁ and -Rh₂.
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