| Polyphenols was extracted from sesame meal by ultrasound-assisted technology. The effects of solvent, ultrasonic power, ultrasonic temperature, ratio of liquid to material and ultrasonic time on the yield of polyphenols were studied by single factor experiment.Then based on Box-Behnken design, four-factor and three-level response surface methodology was carried out to optimize the extraction process, and the antioxidant activity of polyphenols in vitro was also determined. The results showed that the optimal ultrasound-assisted extraction conditions of polyphenols from sesame meal were obtained as follows: 60% ethanol aqueous solution as solvent, ultrasonic power 320 W, ultrasonic temperature 54?℃, ratio of liquid to material 57∶?1 and ultrasonic time 30 min. Under these conditions, the yield of polyphenols was 2.86%, which was not significantly different from the predictive value(2.95%). Compared with TBHQ, the polyphenol extracts from sesame meal had stronger antioxidant activity in vitro. The IC50 of polyphenol extracts from sesame meal on scavenging DPPH free radical was 34.91 μg/mL,lower than that of TBHQ(92.40 μg/mL). |
