Abstract
A simple and precise method was established for the simultaneous determination of five selected marker components in the kampo (Chinese herbal medicine) extract preparation “Heii-San” using high-performance liquid chromatography with tetra-n-amylammonium bromide (TAA) as an ion-pair reagent.
The most efficient extraction of the five components in Heii-San was made by treating the material with 50% methanol as an extraction solvent with stirring for 15 min at room temperature. For the separation of the components, hesperidin, 6-gingerol, honokiol, glycyrrhizin and magnolol, an ODS column was used with multi-step gradient elution with 10 mM TAA (H3PO4, pH 4.0)-acetonitrile as the mobile phase. The acetonitrile content was linearly increased from 25% to 90%. The five main components were eluted within 50 min without interference from coexisting components. The results reveal that the content of the main components, with the exception of hesperidin in the kampo extract preparation was higher than that in oriental pharmaceutical decoctions previously reported.
