Characterization of angiotensin-converting enzyme inhibitory activity of fermented milk produced by Lactobacillus helveticus.

Abstract

Hypertension affects up to 30% of the adult population in most countries. It is a known risk factor for cardiovascular diseases, including coronary heart disease, peripheral artery disease, and stroke. Owing to the increased health awareness of consumers, the application of angiotensin-converting enzyme (ACE)-inhibitory peptides produced by Lactobacillushelveticus to prevent or control high blood pressure has drawn wide attention. A total of 59 L. helveticus strains were isolated from traditional fermented dairy products and the ACE-inhibitory activity of the fermented milks produced with the isolated microorganisms was assayed. The ACE-inhibitory activity of 38 L. helveticus strains was more than 50%, and 3 strains (IMAU80872, IMAU80852, and IMAU80851) expressing the highest ACE-inhibitory activity were selected for further studies. Particularly, the gastrointestinal protease tolerance and thermostability of the ACE-inhibitory activity in the fermented milks were assessed. Based on these 2 criteria, IMAU80872 was found to be superior over the other 2 strains. Furthermore, IMAU80872 exhibited a high in vitro ACE-inhibitory activity at the following fermentation conditions: fermentation temperature at 40°C, inoculation concentration of 1×10(6) cfu/mL, and fermentation for 18h. Finally, by using ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry analysis, we observed changes of the metabolome along the milk fermentation process of IMAU80872. Furthermore, 6 peptides were identified, which might have ACE-inhibitory activity. In conclusion, we identified a novel ACE-inhibitory L. helveticus strain suitable for the production of fermented milk or other functional dairy products.

• Authors: Yongfu Chen, Changkun Li, Jiangang Xue, Lai-yu Kwok, Jie Yang, Heping Zhang, Bilige Menghe
• Journal: Journal of dairy science (J Dairy Sci) Vol. 98 Issue 8 Pg. 5113-24 (Aug 2015) ISSN: 1525-3198 [Electronic] United States
• PMID: 26004829 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Chemical References

• Angiotensin-Converting Enzyme Inhibitors

Topics

• Angiotensin-Converting Enzyme Inhibitors (metabolism)
• Animals
• Chromatography, High Pressure Liquid
• Cultured Milk Products (chemistry, microbiology)
• Gastrointestinal Tract (physiology)
• Hot Temperature
• Lactobacillus helveticus (chemistry)
• Spectrometry, Mass, Electrospray Ionization