Angiotensin-I-converting enzyme inhibitory peptides in milk fermented by indigenous lactic acid bacteria

Abstract

<jats:p>Background and Aim: Fermented milk can be used to produce antihypertensive peptides. Lactic acid bacteria (LAB) with its proteolytic system hydrolyze milk protein during fermentation to produce several peptides, which include antihypertensive bioactive peptides. This study aimed to investigate the ability of indigenous LAB for the production of angiotensin-I-converting enzyme inhibitory (ACE-I) peptides in fermented milk and to characterize the ACEI peptides. Materials and Methods: Reconstituted milk (11%) inoculated with ten LAB isolates, and then incubated at 37°C until it reaches pH 4.6. The evaluation was carried out for LAB count, lactic acid concentration, peptide content, and ACE-I activity. The low molecular weight (MW) peptides (&lt;3 kDa) were identified using Nano LC Ultimate 3000 series system Tandem Q Exactive Plus Orbitrap high-resolution mass spectrometry. Results: The result showed that the ten LAB isolates were able to produce ACE-I in fermented milk with the activities in the range of 22.78±2.55-57.36±5.40%. The activity of ACE-I above 50% produced by Lactobacillus delbrueckii BD7, Lactococcus lactis ssp. lactis BD17, and Lactobacillus kefiri YK4 and JK17, with the highest activity of ACE-I produced by L. kefiri YK4 (IC50 0.261 mg/mL) and L. kefiri JK17 (IC50 0.308 mg/mL). Results of peptide identification showed that L. kefiri YK 4 could release as many as 1329, while L. kefiri JK 17 could release 174 peptides. The peptides produced were 95% derived from casein. The other peptides were from α-lactalbumin, β-lactoglobulin, and serum amyloid A. The peptides produced consisted of 6-19 amino acid residues, with MWs of 634-2079 Dalton and detected at 317-1093 m/z. A total of 30 peptides have been recognized based on literature searches as ACE-I peptides (sequence similarity: 100%). Conclusion: L. kefiri YK4 and JK17 are the potential to be used as starter cultures to produce the bioactive peptide as ACE-I in fermented milk.</jats:p>

Angiotensin-I-Converting Enzyme Inhibitory Peptides in Goat Milk Fermented by Lactic Acid Bacteria Isolated from Fermented Food and Breast Milk

“…Viable counts of the LAB ranged from 9.18 ± 0.46 to 9.79 ± 0.39 log CFU/mL. When the pH reached 4.6, there was no difference in population (Table 1), which is in accordance with previous results obtained by Elkhtab et al (2017) and from fermented cow milk using similar cultures (Rubak et al, 2020). However, the fermentation time to reach pH 4.6 was different between isolates that ranged from 18 to 48 h with titratable acidity ranging from 0.77 ± 0.06 to 0.94 ± 0.04%.…”

Metabolism Characteristics of Lactic Acid Bacteria and the Expanding Applications in Food Industry

“…For example, the main group of lactobacilli in the kefir culture has a strong decomposing effect on milk protein in milk (Dallas et al, 2016). Lactic acid bacteria such as Lactobacillus delbrueckii, Lactococcus lactis, Lentilactobacillus kefiri, Streptococcus thermophilus, Lactobacillus acidophilus, Lacticaseibacillus casei, and Lactobacillus helveticus can produce angiotensin converting enzyme (ACE) inhibitory peptides (Fuglsang et al, 2003;Ramchandran and Shah, 2008;Rai et al, 2017;Daliri et al, 2018;Wu et al, 2019;Rubak et al, 2020). In addition, in Lactococcus lactis, starter lactocepin specificity type may have an important influence on the level of bitterness in low salt-in-moisture cheeses (Pillidge et al, 2003).…”

Cardiovascular Diseases of Developmental Origins: Preventive Aspects of Gut Microbiota-Targeted Therapy

“…One previous study reported that administration with the ACE2 activator or with ANG-(1–7) during pregnancy could alleviate cardiovascular dysfunction in adult SHR offspring [ 92 ]. Another report showed that the antihypertensive effect of probiotics might be due to their ability to produce ACE inhibitory peptides [ 93 ].…”