大豆多肽的降压活性及其相对分子质量分布研究

采用以FAPGG为底物的酶活力检测法对由不同蛋白酶（碱性蛋白酶、胰蛋白酶、风味蛋白酶、木瓜蛋白酶和菠萝蛋白酶）水解制备的大豆多肽的降压活性进行了测定。结果表明,碱性蛋白酶、胰蛋白酶和风味蛋白酶三酶联合水解制备的大豆多肽具有较好的降压活性,其ACE抑制率达62.78%。经超滤发现,5kDa膜滤过液中多肽含量最多,占总量的73.44%,降压活性最强,其ACE抑制率达84.44%。最后,采用SephadexG-25凝胶色谱进一步分离纯化,得到5个峰,其相对分子质量在1 200以下的组分约占75%,其中相对分子质量在250—600左右的组分占47.6%,降压活性最强,ACE抑制率达92.15%。

Study on Antihypertensive Activity and Molecular Weight Distribution of Soybean Peptides

Soybean peptides were prepared by hydrolyzing soy protein isolate with several proteases such as alkaline protease,trypsin,flavor protease,papain and bromelain.The antihypertensive activity of soybean peptides was determined using FAPGG as substrate for the enzyme activity assay.Results showed that the soybean peptides obtained by alkaline protease,trypsin and flavor proteinase combining enzymatic hydrolysis possessed relatively higher antihypertensive activity,which the inhibition rate of ACE reached 62.78%.After ultrafiltration,it was found that the content of peptides in 5kDa membrane filtration liquid were the most,accounting for 73.44% of the total,and the antihypertensive activity were the strongest,which the inhibition rate of ACE reached 84.44%.Finally,further purification using SephadexG-25 gel chromatography occurred 5 peaks,in which the relative molecular mass of components under 1 200 approximately accounted for 75%,and the components of the relative molecular mass in the 250—600 accounted for 47.6%,which antihypertensive activity were the strongest,and the inhibition rate of ACE reached 92.15%.