Chinese Medicine Angelica Quality Evaluation Method

The dried root of Angelica dahurica(Fisch.ex Hoffm.)Benth.et Hook.f. or Angelica dahurica(Fisch.ex Hoffm.)Benth.et Hook.f.var.formosana(Boiss.)Shan et Yuan, which is widely used in clinic, is listed in the Chinese Pharmacopoeia ( known as BaiZhi ) as an important Traditional Chinese Medicine (TCM). 21 samples of Radix Angelica dahurica were purchased from TCM shops or straightly collected from the plant habitats in different places of China. The present study provides the methods to isolate and simultaneously determine the major biological components in Radix Angelica dahurica and HPLC fingerprint chromatogram was also established for the herb. On the other hand, the essential oil was examined by means of GC-MS, and the GC fingerprint chromatogram of the essential oil from Radix Angelica dahurica was determined. Subsequently, the systematic quality evaluation of Radix Angelica dahurica was developed.1. The method of preparative isolation and purification of bergapten, imperatorin and cnidilin, three of the biologically active coumarin compounds, was optimized. The ethanol extraction of Radix Angelica dahurica was partitioned with chloroform and the chloroform layer was subjected to silica-gel column chromatography. After further purification by ODS open column chromatography, the purified components were identified unambiguously to be bergapten, imperatorin and cnidilin by ¹H-NMR and ESI-MS. Therefore, the present study provides a simple, practical and easy-to-operate preparative method to isolate the reference standards with high purity and amount from Radix Angelica dahurica.2. The purified components were simultaneously determined with another two coumarins (osthole and isoimperatorin) by reversed phase high performance liquid chromatography (RP-HPLC). The determination was performed on a Kromasil-C₁₈ column using methanol-water (66:34, v/v) as the mobile phase at a flow rate of 0.8 ml/min, with a UV detector setting at 310 nm. The calibration curves of bergapten, imperatorin, cnidilin, osthole and isoimperatorin were linear over the range of 1.71～51.3 μg·mL^-1(r = 0.999 9), 2.82～84.6 μg·mL^-1(r = 1.00 0), 3.98～39.8 μg·mL^-1(r = 0.999 8), 0.102～2.04 μg·mL^-1(r = 0.999 0) and 2.02～40.4 μg·mL^-1(r = 0.999 8), respectively. The mean recoveries were 98.0%(RSD = 3.7%), 101.9%(RSD = 2.4%), 101.2%(RSD = 2.9%), 96.7%(RSD = 3.3%) and 101.2%(RSD = 1.5%), respectively. The assay was found to be simple and accurate to measure the concentrations of these five compounds in Radix Angelica dahurica.3. The RP-HPLC fingerprint analysis for the quality control of Radix Angelica dahurica was established. Kromasil C₁₈ column (250 mm × 4.6 mm, 5 μm) was used, with mixture of...