Antihypertensive Peptides Specific to Lactobacillus helveticus Fermented Milk

Peptides are well known as nitrogen sources to supply various amino acids for many different organisms, and also have many hormonal functions in our body. Previous studies have reported a secondary role for peptides with specific amino acid sequences that possess biological function in vivo (1-8). To prepare biologically active peptides (bioactive peptides), food ingredients containing protein are generally hydrolyzed by some proteolytic enzymes. In particular, milk proteins such as bovine casein and whey proteins have been used for preparations of bioactive peptides because inexpensive and safe sources are readily available. Various physiologically functional peptides, such as immunostimulating peptides (1), antimicrobial peptides (2), opioid peptides (3), mineral soluble peptides (4) and antihypertensive peptides (5-8) and have been isolated from enzymatic hydrolyzates of raw food materials and fermented food products.