牛骨多肽酶解工艺优化及其抗氧化活性研究

Optimization of Enzymatic Hydrolysis of Bovine Bone Polypeptide and Its Antioxidant Activity Study

采用响应面法对牛骨多肽的酶解工艺进行优化,使用不同孔径滤膜对获得的牛骨多肽进行初步分离,得到3种不同分子量的分级多肽,并分析不同分子量多肽的体外抗氧化活性。试验结果表明:牛骨多肽的酶解最佳工艺为中性蛋白酶与胰蛋白酶的混合比例1︰4、加酶量1.4%、酶解温度39.6℃、酶解时间2.1 h,在此酶解条件下牛骨多肽得率为17.11%±0.24%;牛骨多肽经不同孔径膜处理得到大于5000 Da(多肽Ⅰ),600~5000 Da(多肽Ⅱ)和150~600 Da(多肽Ⅲ)3种分子量的小分子多肽;以DPPH自由基清除率、羟自由基清除率和还原力为指标检测不同分子量多肽及牛骨酶解液的抗氧化活性,结果显示4个样品均具有一定的抗氧化活性,其中分子量150~600 Da(多肽Ⅲ)的活性优于其他样品,在质量浓度10 mg/mL时其DPPH自由基清除活性、羟自由基清除活性及还原力分别为87.89%±0.18%,52.49%±0.22%和0.382±0.02。

The enzymatic hydrolysis process of bovine bone peptides was optimized by response surface methodology.Three kinds of graded peptides with different molecular weights were obtained by preliminary separation of bovine bone peptides with different pore sizes,and their antioxidant activities in vitro were analyzed.The experimental results showed that the optimum enzymolysis technology of bovine bone polypeptide was as follows:the mixing ratio of neutral protease and trypsin 1︰4,the enzyme dosage 1.4%,the enzymolysis temperature 39.6℃,and the enzymolysis time 2.1 h.Under this enzymolysis condition,the yield of bovine bone polypeptide was 17.11%±0.24%.Bovine bone peptides were treated by membranes with different pore sizes to obtain three kinds of small molecular weight peptides,which were more than 5000 Da(polypeptide I),600-5000 Da(polypeptide II)and 150-600 Da(polypeptide III).The antioxidant activities of peptides with different molecular weights and enzymatic hydrolysate of bovine bone were tested with DPPH radical scavenging rate,hydroxyl radical scavenging rate and reducing power as indicators.The results showed that all samples had certain antioxidant activities,among which the activity of polypeptide III with molecular weight of 150-600 Da was better than other samples,and its DPPH radical scavenging activity,hydroxyl radical scavenging activity and reducing power at the concentration of 10 mg/mL were 87.89%±0.18%,52.49%±0.22%and 0.382±0.02,respectively.