Abstract:

By the step-by-step procedure of dilute alkali extraction, trypsinase-catalyzed hydrolysis, protein removal by trichloroacetic acid, ethanol precipitation, and freeze-drying, crude polysaccharide was obtained from Acipenser schrenckii skull. The conditions of dilute alkali extraction and trypsin-catalyzed hydrolysis were optimized by single factor analysis and orthogonal test. Furthermore the prepared product was subjected to composition and structural analysis. Results showed that the optimal extraction and hydrolysis conditions were as follows: extracting crushed dry Acipenser schrenckii skull for 6 h with 3wt% alkali solution, and hydrolyzing the extract for 5 h with trypsinase dosage of 0.6%, respectively. The contents of hexosamine, hexosuronic acid, total sulfate group and N-sulfate group in the polysaccharide were 18.79%, 21.91%, 15.96% and 13.32%, respectively. Moreover, the hexosamine component in this polysaccharide was identified as galactosamine.

Key words: Acipenser schrenckii skull, polysaccharide, extraction, property