A comparative study of upright counter-current chromatography and high-performance liquid chromatography for preparative isolation and purification of phenolic compounds from Magnoliae officinalis

A comparative study of preparative isolation and purification of the phenolic compounds magnolol and honokiol from the Chinese medicinal plant Magnoliae officinalis by upright counter-current chromatography (CCC) and semi-preparative HPLC is presented. The comparison reveals that with a two-phase solvent system composed of light petroleum (bp 60-90 degrees C)-ethyl acetate - tetrachloromethane -methanol water (1:1:8:6:1, v/v), 1250 mg of honokiol and 520 mg of magnolol, with a purity of 98.7 and 99.5%, respectively, were obtained from 2.0 g of a crude sample of Magnoliae officinulis in a single CCC separation. In contrast, semi-preparative HPLC allowed isolation and purification of these two phenolic compounds with significantly lower productivity and higher solvent consumption. Structures of the purified compounds were identified by(1)H and C-13 NMR.