Effects of fermentation conditions on the potential anti‐hypertensive peptides released from yogurt fermented by Lactobacillus helveticus and Flavourzyme®. (22nd November 2016) - Shi, Min
Summary: This study investigates the effects of fermentation conditions on the production of angiotensin‐converting enzyme inhibitory (ACE‐I) peptides in yogurt by Lactobacillus helveticus 881315 ( L. helveticus ) in the presence or absence of Flavourzyme ®, which is derived from a mould, Aspergillus oryzae and used for protein hydrolysis in various industrial applications. Optimal conditions for peptides with the highest ACE‐I activity were 4% (v/w) inoculum size for 8 h without Flavourzyme ® supplementation, and 1% inoculum size for 12 h when combined with Flavourzyme ® . The yogurt fermented by L. helveticus resulted in IC50 values (concentration of inhibitor required to inhibit 50% of ACE activity under the assayed conditions) of 1.47 ± 0.04 and 16.91 ± 0.25 mg mL −1 with and without Flavourzyme ® respectively. Seven fractions of ACE‐I peptides from the yogurt incorporated with L. helveticus and Flavourzyme ® were separated using the preparative high‐performance liquid chromatography. Fraction (F3) showed the highest ACE‐I activity with an IC50 of 35.75 ± 5.48 μg mL −1 . This study indicates that yogurt may be a valuable source of ACE‐I peptides, which may explain the outcomes observed in the experimental and clinical studies and foresee the application of fermented milk proteins into functional foods or dietary supplements. Abstract : The production and separation of anti‐hypertensive peptides released from yogurt fermented by Lactobacillus helveticus and Flavourzyme ® .