Bioaccessibility and bioavailability of cardioprotective peptides from fermented milks with specific strains of Limosilactobacillus fermentum after an ex vivo absorption model

Abstract

The bioaccessibility and bioavailability of angiotensin-converting enzyme (ACE) and cholesterol absorption inhibitory peptides from fermented milks (FM) with Limosilactobacillus fermentum J20 and J23 after being subjected to simulated gastrointestinal digestion (SGD) and to ex vivo absorption models were evaluated. Results showed a peptide absorption (bioavailability) of 7.9% for both FM. FM with L. fermentum J20 and J23 after SGD inhibited ACE with IC₅₀ (protein concentration necessary to inhibit enzyme activity by 50%) of 0.59 ± 0.03 and 0.95 ± 0.00 mg mL⁻¹; respectively, while after the absorption model values of 0.11 ± 0.01 and 0.16 ± 0.07 mg mL⁻¹; respectively, were obtained. Moreover, FM with L. fermentum J20 and J23 presented a relative cholesterol absorption of 3.7% and 4.8%; respectively, both lower (p < 0.05) than the control (13.4%) as shown in the ex vivo absorption model. After an in silico analysis, eleven peptides from FM with J20 showed high (p < 0.01) affinity to ACE binding sites. Also, several highly hydrophobic peptides in FM with J20 may be involved in the inhibition of the micellar solubility of cholesterol. Therefore, these results showed that FM with L. fermentum J20 and J23 have potential cardioprotective effects. Screening of LAB for their industrial application in functional fermented milks may start with the use of in vitro models and in silico studies in order to save time, cost and effort involved in in vivo studies.