Abstract:

Ultrasonic treatment was employed to improve the antioxidant activity of polysaccharides from the mature fruits
of Schisandra chinensis. Based on hydroxyl and DPPH radical scavenging activity, the effects of ultrasonic power and
treatment time on antioxidant activity of polysaccharides were studied. The results showed that both ultrasonic power and
treatment time had significant effects on the antioxidant activity of polysaccharides. The optimal conditions of ultrasonic
treatment were 330 W of ultrasonic power, 20 min of treatment time. Under these conditions, the scavenging rates of
hydroxyl and DPPH radicals were increased from 74.34% to 87.05%, and from 84.43% to 95.05%, respectively. The IC50 of
the treated polysaccharides for scavenging of hydroxyl and DPPH radicals were 10.7 and less than 2 mg/mL, respectively.
In conclusion, appropriate ultrasonic treatment can improve the antioxidant activity of polysaccharides from Schisandra
chinensis fruits.

Key words: Schisandra chinensis, polysaccharides, antioxidant activity, ultrasonic treatment