Water e2695 series hplc system

The contents of calycosin and calycosin-7-O-β-D-glucoside from A. membranaceus extract (A extract) and lithospermic acid from L. erythrorhizon extract (L extract) were measured by HPLC-DAD as active compounds of each plant sample. For HPLC analysis, a YMC ODS-AM (4.6 × 250 mm, 5 μm) column was used at 30 °C with 0.1% formic acid and acetonitrile as the gradient system of the mobile phase in Water e2695 series HPLC system (Waters Corporation, Milford, MA, USA). The mobile phase was maintained at 5% acetonitrile for 3 min, increased to 20% for 3 min and then increased to 28% for 25 min. Then, elution was performed by increasing the mobile phase to 100% acetonitrile for 4 min. The flow rate was 1 ml/min, and the absorbance of the UV detector was measured at a wavelength of 254 nm.

Based on Park et al.’s paper [34 (link)], the profiling of the extract of the dried root of Astragalus membranaceus was analyzed using HPLC. In brief, a YMC ODS-AM (4.6 × 250 mm, 5 μm) column was applied at 30 °C with 0.1% formic acid and acetonitrile as the gradient system of the mobile phase under the Water e2695 series HPLC system (Waters Corporation, Milford, MA, USA). The mobile phase was maintained in 5% acetonitrile for 3 min and increased to 20% for 3 min, and then, up to 28% for 25 min. Then, elution was carried out by increasing the mobile phase to 100% acetonitrile for 4 min with a flow rate of 1 mL/min. The absorbance of the UV detector was measured at a wavelength of 254 nm compared to standard chemicals such as calycosin (99%) and calycosin-7-O-β-D-glucoside (99%) with high purity from ChemFaces (Wuhan, China) and Sigma-Aldrich (St. Louis, MO, USA).