Application of step-wise gradient high-performance counter-current chromatography for rapid preparative separation...

In general, simultaneously separation and purification of components with a broad polarity range from traditional Chinese medicine (TCM) is a challenge by an ordinary high-speed counter-current chromatography (HSCCC) method. In this paper, we describes a rapid and efficient separation method of combining three-step gradient elution and two-step flow-rate gradient elution using high-performance counter-current chromatography (HPCCC) to separate 8 diterpene compounds simultaneously within 80 min in a single run from the alcohol extract of Pseudolarix kaempferi Gordon. This separation process produced 166 mg pseudolaric acid B O-β-d-glucopyranoside (PABGly), 152 mg pseudolaric acid C (PAC), 8 mg deacetylpseudolaric acid A (deacetylPAA), 5 mg pseudolaric acid A O-β-d-glucopyranoside (PAAGly), 484 mg pseudolaric acid B (PAB), 33 mg pseudolaric acid B methyl ester (PAB methyl ester), 10mg pseudolaric acid A (PAA) and 18 mg pseudolaric acid H (PAH) from 1.0 g crude sample with purities of 98.6%, 99.6%, 92.3%, 92.2%, 99.2%, 99.4%, 98.3%, 91.0%, respectively. Our study indicates that the suitable combination of step-wise gradient elution and flow-rate gradient elution using HPCCC is an effective strategy to separate complex components from natural products.