Study on Optimization of Extraction Technology of the Collagen from Andrias davidianus Skin and Its Antioxidant Activity

The extraction rate of collagen from the skin of Andrias davidianus was selected as the index,the suitable organic acid extraction solution type and extraction temperature were studied,and the effects of three factors including acid concentration,solid-liquid ratio and extraction time on the extraction rate of collagen were investigated. Based on single factor test,the extraction process of collagen from Andrias davidianus skin was optimized by orthogonal experiment. After that,the antioxidant activity of collagen from Andrias davidianus skin was evaluated by DPPH and salicylic acid. The results showed that the optimum extraction conditions of collagen from the skin of giant salamander were as follows:The concentration of hydrochloric acid extraction solution was 0.4 mol/L,extraction temperature was 35℃,the ratio of solid to liquid was 1:15 (g/mL),extraction time was 24 h. Under these conditions,collagen extraction rate was 40.2%,the IC₅₀ value of DPPH radical and OH·radical scavenging activities were 9.96 and 7.79 mg/mL,respectively.The research showed that the extraction rate of collagen from Andrias davidianus skin was higher by acid extraction,and the antioxidant activity was better. It provided the theoretical basis for the development application of Andrias davidianus skin.