Studies on Physical and Chemical Quality Evaluation of Crude Drugs Preparations. I. Analysis of Pueraria Radix and Species Puerariae

Abstract

Daidzein, daidzin and puerarin in MeOH extracts of Pueraria Radix and Species Puerariae were analyzed using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). For standards, daidzein, daidzin and puerarin were isolated from Pueraria Radix. For qualitative analysis, TLC was carried out using silica gel plate and CHCl₃-MeOH-H₂O (65 : 35 : 10, lower layer). Daidzein and puerarin were detected by exposing to ultraviolet (UV) light, and daidzin was detected by spraying p-anisaldehyde-H₂SO₄ solution. For determination, HPLC was carried out using Shodex ODS as separation column and CH₃CN-H₂O (15 : 85) as mobile phase. Daidzein and daidzin were determined using UV detector at 254 nm. Puerarin was determined using fluorescence detector at λ_EX 254nm. Samples were extracted with MeOH. The extracts were passed through Sep Pak C₁₈ cartridge and applied to TLC and HPLC. Recoveries of these constituents from model preparation were as follows ; daidzein : 86%, daidzin : 96% and puerarin : 99%, respectively. These methods were considered to be useful for one of evaluations of commercial Pueraria Radix and Species Puerariae.