Abstract: The objective of this study was to optimize the extraction of polyphenols from Cyrtomium fortunei through response surface methodology (RSM).Based on single factor experiments,ultrasonic time,ultrasonic temperature,solid-liquid ratio and ethanol concentration were selected to design Box-Behnken central composite.By means of regression analysis,the results showed that the optimal conditions to extract polyphenols from C.fortunei were as follows:ultrasonic time of 20 min,ultrasonic temperature of 46 ℃,solid-liquid ratio of 1:40 and ethanol concentration of 35%.Under these conditions,the extraction yield of polyphenols reached 8.11660%.Compared with the theoretical value (8.12986%),the RSD was 0.15%.The result indicated that the extraction system was efficient,reliable and practical.

Key words: Cyrtomium fortunei, polyphenols, ultrasonic-assisted, response surface methodology