Abstract:Taking broccoli stems as raw material，glucosinolates（GS）of broccoli stems were extracted by the method of ultrasonic-assisted，and the ultrasonic treatment power，ultrasonic treatment time，extraction temperature，phosphate buffered saline（PBS）buffer concentration，solid-liquid ratio were invested.Based on the single factor tests，Box-Benhnken center composite experiment was carried out with four factors three levels to perform response surface analysis which put the extraction volume of GS as the response values，and the antioxidant activity of the GS was preliminarily explored.The results showed that，the optimal conditions were as follows：ultrasonic power was 80 W，ultrasonic treatment time was 22 min，extraction temperature was 40℃，and solid-liquid ratio was 1∶16 （g/mL）.Under this condition，the extraction volume of GS was 0.732 mg/mL，which was close to the measured value.The relative error between the actual values and predicted values was only 1.1%.Extracts and lyophilizate of broccoli stems were added to the commercial apple juice，the antioxidant value increased significantly （p＜0.05），form 4.08 μmol Trolox/mL to 6.65 μmol Trolox/mL and 9.16 μmol Trolox/mL respectively.The average antioxidant activity was increased of 2-3 times.