ACE-inhibitory peptides from Laminaria japonica and their potential anti-hypertensive mechanism

Abstract

Bioactive peptides have been extensively applied for developing health-promoting foods. To improve the value of Laminaria japonica proteins (LJPs), anti-hypertensive peptides were prepared by using controlled enzymatic hydrolysis along with response surface methodology to improve their yields. Eight anti-hypertensive peptides with tyrosine (Tyr) at the C-terminal were determined through an efficient RP-HPLC method and molecular docking was performed to reveal the underlying mechanisms behind their effectiveness of anti-hypertension. According to the results, the strongest activity of hydrolysates was achieved under enzyme ratio (papain: alcalase: trypsin) 1:2:1, pH 8.0, temperature 60°C, substrate concentration 1.7%, enzyme addition 4.4%, and hydrolysis time 5.1 h. Furthermore, molecular docking results displayed that anti-hypertensive peptides could bind with ACE active sites through forming a stable composite structure, thus causing a significant reduction to activities. These results demonstrated the potential applications of LJPs as a source of anti-hypertensive peptides and provided a reference for the industrialized anti-hypertensive productions.