Optimization of Ultrasonic Assisted Extraction and Antioxidant Activity of Polysaccharide from Gleditsia japonic Miq.

The polysaccharide in Gleditsia japonic Miq. was researched. On the basis of single factor experiment,response surface methodology was used to optimize the ultrasonic extraction process of Gleditsia japonic Miq.,and the antioxidant activity of polysaccharides in vitro was studied. The results showed that the optimum technology conditions were as follows:Extraction temperature 50 ℃,liquid to material ratio 35:1 (mL/g),extraction time 30 min,ultrasonic power 285 W,performed three times,under these conditions,the yield of polysaccharide was 30.65%±0.25%. Antioxidant activity test showed that the polysaccharide in Gleditsia japonic Miq.had certain antioxidant activity,and the IC₅₀ of radical scavenging capacity on O₂^-·,DPPH· and ·OH were 10.3,6.9,1.5 mg/mL,respectively.