Development of whey beverage containing antihypertensive peptides and fermentated with lactic acid bacteria originated from human intestune.

以人体肠道乳酸菌为发酵剂，研制了含有降压肽的乳清乳清饮料。以干酪乳清蛋白为原料，分别用胃酶、胰蛋白酶、胰凝乳酶、蛋白酶K、放线酶E、热裂解酶和木瓜蛋白酶对干酪乳清蛋白进行酶解，并评价其对血管紧张素转换酶(ACE)的抑制活性。胃管插管后测定自发性高血压大鼠(SHR)胃管内血压的变化。活性多肽是从蛋白酶K酶解液中层析得到的。对分离到的5个多肽的氨基酸序列及其来源进行了分析。化学合成的多肽具有抗SHR的降压活性。从SHR的肺中回收到口服Ile-Pro-Ala的三肽。结果表明，Ile-Pro-Ala三肽从肠道吸收，然后移动到肺并与Ace结合。用食品添加剂级放线酶AS、蛋白酶A、Kokulase P和变性酶AP消化干酪乳清时，以放线酶为消化剂的降压活性最高。嗜酸乳杆菌群乳酸菌在干酪乳清中的生长通常较差，但经蛋白酶消化后得到改善。干酪乳清的蛋白酶消化与人体肠道乳酸菌发酵相结合，使双功能乳清饮料的研制成为可能。

Cheese whey beverage containing antihypertensive peptides and fermented with lactic acid bacteria originated from human intestine was developed. Cheese whey proteins were hydrolyzed with pepsin, trypsin, chymotrypsin, proteinase K, actinase E, thermolysin and papain, then evaluated on inhibitory activity against angiotensin converting enzyme (ACE). Strong inhibitory activity was generated by proteinase K and thermolysin digestion.The digests were assayed for changes in the blood pressure of spontaneously hypertensive rats (SHR) after gastric intubation. The active peptides were chromatographically isolated from the protease K digest. Five peptides isolated were clarified amino acid sequences and their origin. Chemically synthesized peptides showed the antihypertensive activity against SHR.A tripeptide of Ile- Pro-Ala which was orally administered to SHR was recovered from lung of SHR.The results indicated that the peptide was absorbed from intestine, then move to lung and bind there with ACE.When cheese whey was digested with food additive grade proteases of actinase AS, proteinase A, kokulase P and denatyme Ap, the highest antihypertensive activity against SHR was observed in actinase AS digest. Growth of Lactobacillus acidophilus group lactic acid bacteria in cheese whey is usually poor but it was improved after digestion with proteases. Combination of protease digestion of cheese whey and fermentation with lactic acid bacteria originated from human intestine made possible development of the double functional whey beverage.