Proteolysis and Process-Induced Modifications in Synbiotic Yogurt Investigated by Peptidomics and Phosphopeptidomics

Abstract

Probiotic and synbiotic yogurt preparations were manufactured at the semi-industrial pilot scale with Lactobacillus acidophilus and Bifidobacteria strains without inulin or fortified with 1 and 3% (w/w) inulin. The pathway of casein breakdown was determined in probiotic, synbiotic, conventional yogurt, and nonstarted milk base using HPLC−ESI-MS/MS-based peptidomics and phosphopeptidomics; in the latter case, casein phosphorylated peptides (CPPs) were previously enriched by hydroxyapatite chromatography. Compared with traditional yogurt, casein proteolysis increased in probiotic and even more in synbiotic yogurt with 1% inulin. Fortification with 3% inulin greatly modified the proteolytic pattern, indicating a characteristic contribution of probiotics to proteolysis. The enhanced proteolysis in synbiotic yogurt exposed the neo-formed peptides to progressively increase enzymatic or chemical modifications, such as dephosphorylation of CPPs, methionine oxidation, and formation of N-terminal pyroglutamic acids. These modifications might constitute molecular signature descriptors of metabolic processes mediated by complex bacterial communities, with technological, nutritional, and sensorial significance.

Theoretical benefits of yogurt-derived bioactive peptides and probiotics in COVID-19 patients – A narrative review and hypotheses

“…The presence of proline-rich peptides within the sequenced casein-derived peptides supports the hypothesis stating that intestinal or peptic hydrolysis gives bradykinin potentiation characteristics to these peptides. Subsequently, enhanced yogurt proteolysis exposes the formed peptides to further modifications as the formation of N-terminal pyroglutamic acids ( Pinto et al, 2020 ). Bovine casein-derived ACE-inhibitory peptides which share the common amino acid sequence at C-terminal (Pro-Pro or Ala-Pro) with snake venom-derived BBPs, exhibit almost equal effects on ACE and bradykinin ( Maruyama et al, 1985 ).…”

Integrated metabolomics and peptidomics to delineate characteristic metabolites in milk fermented with novel Lactiplantibacillus plantarum L3

“…These findings confirmed that the stability of whey proteins to hydrolysis is higher than that of CN. The relative stability of whey proteins is attributed to the conformational stability of globular proteins rather than the specificity of LAB proteases ( Pinto, Picariello, Addeo, Chianese, Scaloni, & Caira, 2020 ). The above results indicated that L. plantarum L3 exhibited a good protein degradation capacity and its secreted peptidase hydrolyzed CN to release BPs.…”

Influence of Oat β-Glucan on the Survival and Proteolytic Activity of Lactobacillus rhamnosus GG in Milk Fermentation: Optimization by Response Surface

“…In fact, different investigations have shown that some potential prebiotic materials integrated in production of fermented milks and ripened cheeses activate the proteolytic system of lactic acid bacteria in special those like-probiotics [17,47]. Recently, Habibi-Najafi et al [48] and Pinto et al [49] have reported the activation of the endoproteolytic system of different lactobacillus integrated into the manufacturing of symbiotic yogurt enriched by inulin, with activation being dependent on carbon source concentration. Furthermore, they conclude over the importance in the peptides production induced by the activation of some important peptidases, which are regulated by glucose.…”