| Natural sulfhydryl compounds have attracted more and more attention because of their advantages of high physiological activity and low toxicity and side effects. In order to obtain natural sulfhydryl peptides, flaxseed protein was extracted from low-temperature pressed flaxseed cake, and further enzymatically hydrolyzed to prepare flaxseed protein hydrolysates rich in sulfhydryl. Flaxseed sulfhydryl peptide was enriched by covalent chromatography. Firstly, the protease was screened, and then the enzymatic hydrolysis process was optimized by single factor experiment and orthogonal experiment with enzymatic hydrolysis temperature, pH, enzymatic hydrolysis time, enzyme dosage and solid-liquid ratio as investigation factors and sulfhydryl content as evaluation index. Thiopropyl Crystarose 6 Fast Flow gel was used for selective adsorption and desorption of sulfhydryl peptides from flaxseed protein hydrolysates, and the amino acid composition of flaxseed sulfhydryl peptide was analyzed. The results showed that the optimal enzymatic hydrolysis conditions were obtained as follows: using papain, enzymatic hydrolysis temperature 55℃, pH 7.0, enzymatic hydrolysis time 4 h, enzyme dosage 3% and solid-liquid ratio 1∶60. Under these conditions, the sulfhydryl content in flaxseed protein hydrolysates was 16.69 μmol/g, and it was 71.13 μmol/g after enrichment. Compared with flaxseed protein, the proportion of sulfhydryl amino acids in flaxseed sulfhydryl peptides increased. In summary, with low-temperature pressed flaxseed cake as raw material, flaxseed sulfhydryl peptide can be obtained by protein extraction, enzymatic hydrolysis and covalent chromatography enrichment. |
