Comparative Peptidomics Analysis of Milk Fermented by Lactobacillus helveticus

Lactobacillus helveticus is one of the commonly used starter cultures for manufacturing various fermented dairy products. However, only a few studies have explored the cleavage region preference of L. helveticus with different cell envelope proteinase (CEP) genes. In the present study, we profiled the peptide composition of milk samples fermented by three different L. helveticus strains by means of peptidomics to illustrate their different proteolysis patterns. The result revealed that the differences in peptide profiles of milk samples fermented by different L. helveticus strains were mainly a result of variations in the peptide patterns of the casein fractions, which were correlated with CEP genotypes. This was mainly reflected in the extensiveness of the hydrolysis region of alpha S1-casein and the degree of beta-casein hydrolysis. Bioactive peptides were mostly derived from the hydrolysis region common to the three L. helveticus strains, and DQHXN-Q32M42 fermentation resulted in the highest diversity and abundance of bioactive peptides and a significant antihypertensive effect in spontaneous hypertension rats.

Automated summary

This study investigated the proteolysis patterns of different Lactobacillus helveticus strains with different cell envelope proteinase (CEP) genes during milk fermentation using peptidomics. The results showed that variations in peptide patterns of casein fractions were correlated with CEP genotypes, and the bioactive peptides derived from the common hydrolysis region exhibited antihypertensive effects.