Abstract:

This study aimed to establish an optimized method using ultrasonic-assisted alcalase hydrolysis for the preparation of oat-derived ACE inhibitory peptides. On the basis of single factor experiments that were done for exploring the effects of ultrasonic frequency, power and treatment time, temperature, enzymolysis time and enzyme dosage on degree of hydrolysis (DH) of oat and ACE inhibitory activity of products, the interactive effects of four crucial technological parameters, including ultrasonic treatment time and power, temperature and enzymolysis time were assessed by response surface methodology (RSA) involving a three-level central composite design and multiple regression analysis. Results showed that the optimal preparation process of oat-derived ACE inhibitory peptides was based on enzymolysis for 2.25 h at 55.05 ℃ following ultrasonic treatment for 28.40 min at 190.08 W and the same temperature. Under such conditions, oat peptides with 87.50% ACE inhibitory activity and 8 mg/ml concentration were obtained.

Key words: oat, ACE inhibitory peptides, ultrasonic, enzymolysis, RSA