ABSTRACT
OBJECTIVE：To optimize the extraction technology for total triterpenes from the leaves of Cornus officinalis . METHODS：Based on the full swelling of the leaves of C. officinalis ，total triterpenes was extracted with heating reflux method. The effects of ethanol concentration ，liquid-solid ratio ，extraction time and extraction times on the contents of total triterpenes from the leaves of C. officinalis were investigated by single factor test. Using oleanolic acid as control ，the contents of total triterpenes were detected by UV spectrometry. On the basis of single factor test ，fixing the times of extraction a s 3 times，taking the contents of total triterpenes as response value ，using ethanol volume fraction ，solid-liquid ratio and extraction time as factors ， Box-Behnken design-response methodology was used to optimize the extraction technology of total triterpenes from the leaves of C. officinalis，and the optimized extraction technology was validated. RESULTS ：The optimal extraction technology of total triterpenes from the leaves of C. officinalis were as follows as ethanol concentration of 73％，liquid-to-material ratio of 38 ∶ 1（mL/g）， extraction time of 60 min. Results of 3 validation tests showed that the contents of total triterpenes from the leaves of C. officinalis were 6.92％，6.91％，6.84％；the average content was 6.89％（RSD＝0.63％），relative error of which with the predicted value （7.28％）was 5.36％. CONCLUSIONS ：The optimized technology is stable and reliable ，and can be used for the extraction of total triterpenes from leaves of C. officinalis .