Abstract:In this paper, the preparation process of Cryptotympana Atrata Peptide (CA-Peptide) was optimized, and the immunomodulatory activities of CA-Peptide and Cryptotympana Atrata Protein (CA-protein) were compared. The optimal preparation process: 4% alkaline proteinase 37071 (m/m) and 4% trypsin enzymolysis (m/m), 5% substrate concentration (m/m), initial pH 10.5, enzyme temperature 50℃, two kinds of protease enzymolysis for 1.5 hours respectively. Animal experiments showed that the related indexes of immunocompromised mice induced by cyclophosphamide all could be improved in different degrees by CA-Peptide and CA-Protein. At the same dose, the spleen index and proliferation rate of splenic lymphocytes in CA-Peptide group (2.40 mg/g and 51.07%, respectively) were significantly (P<0.05) higher than those of CA-Protein group. The immunoglobulin G, immunoglobulin A, immunoglobulin M, tumor necrosis factor-α, interleukin-4 and interleukin-10 in CA-Peptide group (701.67, 299.19, 239.88, 20.11, 33.86 and 71.15 ng/L, respectively) were significantly (P<0.05) higher than those of CA-Protein group. The thymus index and serum interferon-γ in CA-Peptide group (1.36 mg/g and 36.26 ng/L, respectively) were significantly (P<0.05) lower than those of CA-Protein group. There was no significant difference in natural killer cell activity and serum interleukin-2 level between CA-Peptide group and CA-Protein group (P > 0.05). In conclusion, the enzymatic hydrolysis process significantly changes immunomodulatory activity of CA-Protein, and the product CA-Peptide has better improvement on many immune indexes than CA-Protein.
