Quantitative Analysis of Bioactive Components in Chinese Herb Medicine by HPLC

Abstract

Dao-Chi San (DCS) is one of the famous anti-inflammatory Chinese medicinal prescriptions for urinary infection. Of the 4 component drugs, Glycyrrhizae Radix and Crude Rehmanniae Radix are the main anti-inflammatory drugs in DCS. Glycyrrhizin and catalpol are the principle components of the prescription, respectively. A high performance liquid chromatographic method for the determination of catalpol and glycyrrhizin in DCS was established. The separation for catalpol was performed on a LiChrospher 100 RP-18e column with 0.6% CH3CN as the mobile phase at a flow rate of 1.0 ml/min, with detection at 210 nm. Analysis for glycyrrhizin was performed on an RP-18e column with CH3CN- 0.2% acetic acid (35:65) as the mobile phase, at a flow rate of 1.0 ml/min and detection at 254 nm. The retention times of catalpol and glycyrrhizin were 10.6 min and 18.6 min, respectively. A good linear relationship was obtained in the concentration range studied, and the method was sufficiently accurate and precise for use in quality control of traditional Chinese medicinal prescriptions. Thus, we quantitatively analyzed the two principle anti-inflammatory constituents of standard decoction and three concentrated DCS products from the Chinese medicinal pharmaceutical industries. The results show that market concentrations of DCS contain catalpol in the range of 15.84~20.88 (mg/daily dose) and glycyrrhizin in the range of 124.02~146.34 (mg/daily dose). Comparison of the contents of the marker 3 substances in commercial preparations shows that they are variable. In order to promote safety, and reproducible efficacious use in Chinese medicinal preparations, our aim was to develop simple and expedient analytical methods for routine quality control in the pharmaceutical industry.