Abstract: The objective of this study was to optimize the extraction of triterpenes from Kalimeris indica through response surface methodology.Based on single factor tests, Box-Behnken central composite design was applied to investigate the effects of ethanol concentration,solid/liquid ratio,ultrasonic duration,times of ultrasonic on the extraction yield of triterpenes and hence to optimize these extraction conditions.By means of regression analysis,the results showed that the optimized conditions were:ethanol concentration of 40%,solid/liquid ratio of 1:18 g/mL,extraction duration of 1 h and with 4 times of extraction.Under these conditions,the extraction yield of triterpenes reached 26.83 mg/g.The result indicated that the extraction system was efficient and reliable.

Key words: Kalimeris indica, extraction of triterpenes, extraction technology, response surface methodology