Study On The Extraction Process Of Ursolic Acid From Eriobotrya Japonica Leaves

Ursolic acid belongs to triterpenic acid, it has tranquilization, anti-inflammation, strength immunity, anti-bacteria, beautiful white and anti-tumor functions, and it was experimental proved having the hope to become a new potent natural anti-cancer medicine of low-poison & high-validity by the tumor hospital of Chinese academy of medical science. So much more attention has been paid to the studies of ursolic acid in recent years.This paper summarized the research advance of ursolic acid in recent years, including the pharmacutical functions ,clinical uses, original plants and analysis methods; Finding a practical process of isolating & purifying ursolic acid from Eriobotrya leaves of Yunnan .Studied three analysis methods of ursolic acid and determined analysis methods in accordance with the process. The best process obtained is as follows:(1) Dried powder of Eriobotrya leaves were extracted with 12 times absolute EtOH for 10 hours and the EtOH solution was concentrated using a vacuum rotary evaporator to give a crude residue.(2) The residue was dissolved in 20-25 times petroleum ether for 4 times(25 hours for each times) and then purified by EtOH for 3-4 times .(3) The crude product was repurified by silica gel column for further isolation .The colum was eluted with CH₃Cl at a flow rate of 72ml/hr, then recrystal in absolute EtOH at -5℃,finally afforded a white needles crystal. Determination of ursolic acid in the product by HPLC showed that the content was above 95.3%.