A Study on Ultrasonic Extraction Technology for Gold Tea Polysaccharide and Its Ecto Antioxidant Activity
To study the extraction technology for gold tea polysaccharide and its antioxidant activity in vitro.L9(34) orthogonal test was performed to extract gold tea polysaccharides by ultrasonic extraction method, and the results were analyzed by variance analysis and multiple comparison method.The single factors(ultrasonic power,ultrasonic time,solid-liquid ratio,ultrasonic temperature) were optimized,and the antioxidant activity wasevaluated by measuring the free radical scavenging ability and the reducing capacity of gold tea polysaccharide. The optimum extraction conditions were ultrasonic power 165 W,ultrasonic time 40 min,ratio of material to liq-uid 1:40,ultrasonic temperature 65 ℃.The highest yield of gold tea polysaccharide was 11.23%.The scaven-ging ability of DPPH,·OH and superoxide anion radical and the reducing capacity of gold tea polysaccharide were lower than those of Vc (P<0.01).In comparison with Vc,0.2 mg/mL of gold tea polysaccharide had a significant difference in free radical scavenging ability of ABTS+. The half-inhibiting concentrations of gold tea polysaccharide to IC50 of ·OH and ABTS+radicals were 1.713 and 0.553 mg/mL,respectively (P<0.01).The content of polysaccharide in gold tea is high,the higher the polysaccharide concentration is,the stronger the an-tioxidant activity is.