Extraction Process Optimization，Purification and Characterization Analysis of Glycoprotein from the Mucus of Chinese Giant Salamander

The extraction process of crude glycoprotein from Chinese giant salamander (MGP) mucus cultured in Lishui was optimized. The crude glycoprotein was further purified, of which characterization was analysed. Based on single factor experiment, the extraction process was optimized by response surface methodology with solid-liquid ratio, temperature, extraction concentration, extraction time as factors, and glycoprotein yield as index. The results showed that the optimal extraction conditions were solid-liquid ratio of 1:30.5 g/mL, extraction temperature of 51 ℃, extraction concentration of 0.32 mol/L, extraction time of 5.2 h, the highest yield of MGP was 5.22%±0.71%, which was basically consistent with the expected results. The electrophoresis pure of purified glycoprotein was determined. The lyophilized MGP was white, loose powder, of which molecular weight was about 29 kDa. The contents of essential amino acids and medicinal amino acids in MGP were 37.21 g/100 g and 33.39 g/100 g, respectively. MGP had a typical glycoprotein structure of UV full wavelength absorption image, containing o-glycopeptide bond, pyranose ring structure and β-glycosidic bond. The secondary structure of MGP was mainly composed of 87% β-folded, which provided a theoretical basis for further research on the biological activity of glycoprotein from the mucus of Chinese giant salamander.