龙须菜蛋白的提取工艺优化及降血压组分制备

目的 优化龙须菜蛋白的提取工艺,并制备降血压组分.方法 从胃蛋白酶、中性蛋白酶、碱性蛋白酶和胰蛋白酶中筛选能获得最佳蛋白提取率的蛋白酶,采用单因素试验考查pH、底物浓度、酶解温度、酶底比、酶解时间对蛋白提取率和ACE抑制率的影响,采用响应面法确定最佳工艺条件,采用超滤膜分离技术龙须菜蛋白酶解液中制备血管紧张素转换酶(a...

Optimization of extraction technology of Gracilariopsis lemaneiformis protein and preparation of blood pressure lowering components

Objective To optimize the extraction process of protein from Gracilariopsis lemaneiformis, and prepare blood pressure lowering components. Methods The protease which could obtain the optimal protein extraction rate was screened from pepsin, neutral protease, alkaline protease, trypsin. The effects of pH, substrate concentration, enzymolysis temperature, enzymolysis ratio and enzymolysis time on protein extraction rates and ACE inhibition rates were investigated by single factor test. Response surface methodology was used to determine the optimal process conditions, the angiotensin converting enzyme(ACE) inhibitory peptides were prepared by ultra-filtration membrane separation technique from the proteolysis solution of Gracilariopsis lemaneiformis, and the ACE inhibition rate was investigated. Results The optimal enzymatic hydrolysis process was: The pH 8.4, substrate concentration 18%, enzymolysis temperature 55 ℃, ratio of enzyme to substrate 2.0%, alkaline protease enzymatic hydrolysis for 3 h. Under these conditions, the protein recovery was(19.54±0.56)% and ACE inhibition rate was(91.12±0.17)%;the hypotensive activity of the enzymolysis solution was verified by the ACE inhibition rate of 10, 5 and 1 kDa ultra-filtration membranes. The ACE activity of the enzymolysis solution of 1 kDa ultra-filtration membrane was the highest, reaching(71.37±0.22)%. Conclusion Gracilariopsis lemaneiformis can be used as a high quality resource for the separation and purification of hypotensive peptide.