Abstract: In this paper,the preparation of artemisinic acid from Artemisia annua L.was investigated and its biological stability was explored.Liquidliquid extraction method and adsorptive separation method were used to prepare artemisinic acid from A.annua,and spectroscopic,mass spectrometry and melting point method were adopted to characterize artemisinic acid crystals.The biological stability of artemisinic acid was analyzed using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC).Artemisinic acid crystal was successfully obtained by liquidliquid extraction method and Adsorptive separation method,and the yield of product reached to 61.7% and the purity of product was higher than 96%.Artemisinic acid was very stable under the conditions of 4 oC,room temperature,60 ^oC and natural lighting for 30 d.Furthermore,it was stably preserved in plant for a year with its content maintained at the same level.The structure of product was badly destructed by UV light,and it was not detected after lighting for 6 h.In conclusion,high purity of artemisinic acid could be obtained by the developed preparation methods.It was more stable at the conditions of natural light and temperature,and the artemisinic acid could save one year in vivo and in vitro. However,UV light strongly destroy artemisinic acid.

Key words: Artemisia annua L., artemisinic acid;preparation technology;biological stability