The development of angiotensin I-converting enzyme inhibitor derived from chicken bone protein

In order to produce angiotensin I-converting enzyme (ACE) inhibitor for application in functional food, chicken bones were gathered from a meat processing factory and then hydrolyzed with Alcalase, pepsin and trypsin for 12 h. The hydrolysates were lyophilized, stored at -80 degrees C and tested experimentally every 2 h for pH value, peptide content, degree of hydrolysis (DH), electrophoresis and activity of ACE inhibitor. The hydrolysates of Alcalase had the highest peptide content and DH. The components of more than 66 kDa had disappeared in hydrolysates of Alcalase and trypsin after 2 h of hydrolysis. The hydrolysates of Alcalase were more active in inhibiting ACE, especially when hydrolyzed at 4 and 8 h, and also had low IC50 values of 1.960 and 0.945 mg/mL. According to the results of DH and electrophoresis, the higher activity of ACE inhibitor is assumed to be derived from the low molecular peptides in hydrolysates of Alcalase. Chicken leg bone has a high potential to be utilized to develop ACE inhibitory peptides as a potential ingredient of functional food intended to alleviate hypertension.