HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Mizuno, S. Articles by Yamamoto, N. Search for Related Content PubMed PubMed Citation Articles by Mizuno, S. Articles by Yamamoto, N.

Release of Short and Proline-Rich Antihypertensive Peptides from Casein Hydrolysate with an Aspergillus oryzae Protease

R&D Center, Calpis Co., Ltd., 11-10, 5-Chome, Fuchinobe, Sagamihara, Kanagawa 229-0006, Japan

Corresponding author: N. Yamamoto; e-mail: naoyuki.yamamoto{at}calpis.co.jp.

Angiotensin-I converting enzyme inhibitory activities were measured after hydrolysis of casein by 9 different commercially available proteolytic enzymes. Among these enzymes, a protease isolated from Aspergillus oryzae showed the highest angiotensin-I converting enzyme inhibitory activity per peptide. The A. oryzae peptide also showed the highest antihypertensive effect in spontaneously hypertensive rats when the systolic blood pressure was measured 5 h after oral administration of 32 mg/kg of various enzymatic hydrolysates. Significant antihypertensive effects were observed with dosages of 9.6, 32, and 96 mg of the A. oryzae peptide/kg of body weight (BW), and the effects were dependent on these peptide dosages.

Analysis of peptide length showed the A. oryzae hydrolysate was the shortest of all tested casein hydrolysates; the peptide mixture had an average value of 1.4 amino acids (AA) in the sequence. To further characterize the A. oryzae hydrolysate, we analyzed the AA sequence of the whole peptide mixture. Various AA were detected at the first AA position, however, an increased number of Pro residues were observed at the second and third position of the A. oryzae hydrolysate. No strong signals were detected after the fourth AA position of the A. oryzae hydrolysate. These results suggest that the casein hydrolysate of A. oryzae, which expressed potent antihypertensive effects in spontaneously hypertensive rats, mainly contain short peptides of X-Pro and X-Pro-Pro sequences.

Key Words: antihypertensive peptide • angiotensin-I converting enzyme • Aspergillus oryzae protease • casein hydrolysate

Abbreviation key: ACE = angiotensin-I converting enzyme, FOSHU = Food for Specified Health Use, SBP = systolic blood pressure, SHR = spontaneously hypertensive rats.

This article has been cited by other articles:

				M. F. Engberink, E. G. Schouten, F. J. Kok, L. A.J. van Mierlo, I. A. Brouwer, and J. M. Geleijnse Lactotripeptides Show No Effect on Human Blood Pressure: Results From a Double-Blind Randomized Controlled Trial Hypertension, February 1, 2008; 51(2): 399 - 405. [Abstract] [Full Text] [PDF]

				M. Foltz, E. E. Meynen, V. Bianco, C. van Platerink, T. M. M. G. Koning, and J. Kloek Angiotensin Converting Enzyme Inhibitory Peptides from a Lactotripeptide-Enriched Milk Beverage Are Absorbed Intact into the Circulation J. Nutr., April 1, 2007; 137(4): 953 - 958. [Abstract] [Full Text] [PDF]