不同季节虎杖根茎与茎叶中大黄素含量变化研究

目的通过测定药用植物虎杖在不同季节时其不同生长部位中的有效成分大黄素含量及其变化规律，旨在为虎杖的最佳采收时间提供依据。方法采用高效液相色谱法，Diamonsil—C18（250mm×4．6mm，5μm）色谱柱，甲醇-0．1％磷酸（80：20）为流动相；检测波长：254nm；流速：1．0mL／min；柱温：27℃；进样量：20μL。结果通过测定不同季节虎杖的茎叶与根中的大黄素含量，发现根中大黄素含量最高，且大黄素含量在8月最高。结论虎杖在生长发育过程中，大黄素含量变化是有规律的，可根据其根中的大黄素含量确定最佳的采收时间。

Study on Emodin Contents in Rhizome and Stem Leaf of Polygonum Cuspidatum Gathered in Different Seasons

Objective To find the changing regularity of emodin content in different tissues of Polygonum cuspidatum gathered in different seasons by HPLC, so to decide the best gathering time. Methods The separation was performed on Diamonsil-C18 （250 mm×4.6 mm, 5 μm） column, using methanol-0.1%H3PO4 （80 ： 20） as mobile phase, detected at 254 nm. The flow rate was 1.0 mL/min, the column temperature was 27℃. Results Among the rhizome and stem leaf of Polygonum cuspidatum, the content of emodin in the rhizome was the highest. Over a year, the content of emodin was the highest in august. Conclusion The content of emodin changes regularly in the process of growth and development of Polygouum cuspidatum, The best gathering time could be determined by the emodin content in the rhizome of Polygouum cuspidatum.