ABSTRACT
AIM: To specify optimization of the concentration, purification and drying for prepar ati on of Yuxianling Grannles and decrease the dosage on condition that is retentive of potency in order to provide a basis for mass production. METHODS: The contents of ferulic acid and the amount of extract wer e used as marker, the optimium of concentration, purification and drying for pr eparation were selected by orthogonal design and contrast test during aqueous ex tract alcohol precipitation process. RESULTS: Condition was optimum of herb-to-extract ratio in the range of 0.5 ∶1, pr ecipitation with ethanol containing 40% water and drying temperature not to exce ed 60℃ . CONCLUSION: The highest yield of active priciples is obtained by c ondition above.