中文摘要：

目的建立地黄中益母草苷的分析方法，研究地黄在炮制过程中环烯醚萜苷类成分的变化规律。方法采用反相高效液相色谱法，以Hypersil GOLD—C18（4．6mm×250mm，5μm）为色谱柱，流动相为乙腈．水（3：97），流速为1mL·min^-1，检测波长203nm，柱温为40℃。结果益母草苷进样质量浓度在0．0221-0．1326mg·L^-1内，线性关系良好，r为0．9999，平均加样回收率为103．1％。结论本方法可用于熟地黄药材的质量控制。随着蒸制次数的增加，益母草苷作为环烯醚萜单糖苷，在熟地黄中的含量同梓醇一样呈逐渐减少的趋势，最后几乎全部降解。

英文摘要：

OBJECTIVE To establish the qualitative method for leonuride and study the changes of iridoid compounds contents in roots of Radix Rehmanniae.METHODS The RP-HPLC methods was used. The analytical column was a Hypersil GOLD-C18 column （4.6 mm×250 mm, 5 μm）, using the mobile phase of acetonitrile-water （3 ： 97） with a flow rate at 1.0 mL.minl, the detection wavelength was set at 203 nm and column temperature was 40 ℃. RESULTS The calibration curves of leonuride had a good linearity in the range of 0.022 1-0.132 6 mg.L^-1 （r=0.999 9）. The average recovery was 103.1%. CONCLUSION The methods can be used for the quality control of Radix Rehmanniae Praeparata. The contents of catalpol and leonuride were decreased with the increase of processing times, and could be completely degraded at last.