Dry-Cured Ham-Derived Peptide (Asp-Leu-Glu-Glu) Exerts Cytoprotective Capacity in Human Intestinal Epithelial Caco-2 Cells

Antioxidative and mineral-binding food-derived peptides: Production, functions, metal complexation conditions, and digestive fate

The discovery of food-derived biopeptides is becoming increasingly prevalent in the scientific community. Some peptides possess multiple biological functions that can confer health benefits through various mechanisms following ingestion. The present review targets food-derived antioxidant and mineral-binding peptides (AMBPs) including their production procedure i.e., enzymolysis, separation, and purification (through membrane separation, gel filtration, ion exchange chromatography, and high-performance liquid chromatography), followed by mass spectrometry for identification. The most effective AMBPs exhibit radical scavenging activity, detoxification of excess metals, and reduction of lipid peroxidation to facilitate mineral bioavailability. The metal complexation of AMBPs necessitates an optimal metal-to-peptide ratio, specific ligands, precursors, and complexation reactions. The bioavailability and absorbability mechanisms of AMBPs are also elucidated, encompassing gastrointestinal stability, binding mode, and cell absorption machinery. Ultimately, further considerations regarding additional research on AMBPs are provided, which will assist researchers in conducting more comprehensive studies to promote the effective and safe use of AMBPs.

Antioxidant and anti-inflammatory peptides in dry-fermented sausages fermented with Staphylococcus simulans QB7

This study focused on investigating the impacts of Staphylococcus simulans QB7 (S. simulans QB7) on the generation of antioxidant and anti-inflammatory peptides in dry-fermented sausages and the associated mechanisms by in silico. S. simulans QB7 remarkably increased (P < 0.05) the peptide concentration, antioxidant, and anti-inflammatory capacity of peptide extracts. There were 29 peptide sequences with potential activities of antioxidation and anti-inflammation according to BIOPEP-UWM prediction. Molecular docking results indicated that peptide GPGPWG can bind to Kelch-like ECH-associated protein 1 (Keap1) with highest interaction energy, while peptide ANPILEAFG showed highest interaction energy towards p65, I kappa B kinase 2 (IKK-β), c-Jun N-terminal kinases (JNK), and p38 kinases (p38) due to form salt bridge, h-bond, and pi-alkyl. These results suggested that S. simulans QB7 promoted antioxidant and anti-inflammatory peptide generation within dry-fermented sausages.

Unlocking the potential of chicken liver byproducts: Identification of antioxidant peptides through in silico approaches and anti-aging effects of a selected peptide in Caenorhabditis elegans

Chicken meat processing generates a substantial number of byproducts, which are either underutilized or improperly disposed. In this study, we employed in silico approaches to identify antioxidant peptides in chicken liver byproducts. Notably, the peptide WYR exhibited remarkable 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity with an IC50 of 0.13 ± 0.01 mg/mL and demonstrated stability under various conditions, including thermal, pH, NaCl, and simulated gastrointestinal digestion. Molecular docking analysis revealed significant hydrogen bonding interactions, while molecular dynamics showed differential stability with ABTS and 2,2-Diphenyl-1-picrylhydrazyl (DPPH). WYR exhibited improved stress resistance, decreased levels of reactive oxygen species (ROS), elevated the activities of superoxide dismutase (SOD) and catalase (CAT), and modulated the expression of crucial genes through the insulin/insulin-like growth factor (IIS) signaling pathway, mitogen-activated protein kinase (MAPK), and heat shock transcription factor-1 (HSF-1) pathways. These effects collectively contributed to the extension of Caenorhabditis elegans' lifespan. This study not only provides an effective method for antioxidant peptide analysis but also highlights the potential for enhancing the utilization of poultry byproducts.

Studying Antifatigue Mechanism of Tyr-Pro-Leu-Pro in Exercise Mice Using Label-Free Proteomics

In our previous study, yeast-derived peptide Tyr-Pro-Leu-Pro (YPLP) was found to prolong treadmill time and relieve muscle fatigue in ICR mice. The present study aimed to further investigate the antifatigue mechanism of YPLP. Three doses of YPLP (10, 25, and 50 mg/kg·d) were given to exercise mice for 4 weeks. Results showed that YPLP reduced the oxidative response via the nuclear factor erythroid-2-related factor 2 (Nrf2) pathway and promoted energy metabolism through the AMP-activated protein kinase (AMPK) pathway. Label-free proteomics results showed that 81 differential abundance proteins (DAPs) were regulated by high-dose YPLP. These DAPs belonged to proteasome, mitochondrial, and muscle proteins. YPLP was mainly involved in proteasome, aminoacyl-tRNA biosynthesis, focal adhesion, and MAPK signal pathways to enhance muscle endurance. Furthermore, real-time quantitative PCR and Western blotting results proved that YPLP upregulated Psmd14 expression and downregulated p38 MAPK expression. Overall, this study revealed the mechanism behind YPLP to alleviate exercise fatigue.

From In Silico to a Cellular Model: Molecular Docking Approach to Evaluate Antioxidant Bioactive Peptides

The increasing need to counteract the redox imbalance in chronic diseases leads to focusing research on compounds with antioxidant activity. Among natural molecules with health-promoting effects on many body functions, bioactive peptides are gaining interest. They are protein fragments of 2–20 amino acids that can be released by various mechanisms, such as gastrointestinal digestion, food processing and microbial fermentation. Recent studies report the effects of bioactive peptides in the cellular environment, and there is evidence that these compounds can exert their action by modulating specific pathways. This review focuses on the newest approaches to the structure–function correlation of the antioxidant bioactive peptides, considering their molecular mechanism, by evaluating the activation of specific signaling pathways that are linked to antioxidant systems. The correlation between the results of in silico molecular docking analysis and the effects in a cellular model was highlighted. This knowledge is fundamental in order to propose the use of bioactive peptides as ingredients in functional foods or nutraceuticals.

Food Protein-Derived Antioxidant Peptides: Molecular Mechanism, Stability and Bioavailability

The antioxidant activity of protein-derived peptides was one of the first to be revealed among the more than 50 known peptide bioactivities to date. The exploitation value associated with food-derived antioxidant peptides is mainly attributed to their natural properties and effectiveness as food preservatives and in disease prevention, management, and treatment. An increasing number of antioxidant active peptides have been identified from a variety of renewable sources, including terrestrial and aquatic organisms and their processing by-products. This has important implications for alleviating population pressure, avoiding environmental problems, and promoting a sustainable shift in consumption. To identify such opportunities, we conducted a systematic literature review of recent research advances in food-derived antioxidant peptides, with particular reference to their biological effects, mechanisms, digestive stability, and bioaccessibility. In this review, 515 potentially relevant papers were identified from a preliminary search of the academic databases PubMed, Google Scholar, and Scopus. After removing non-thematic articles, articles without full text, and other quality-related factors, 52 review articles and 122 full research papers remained for analysis and reference. The findings highlighted chemical and biological evidence for a wide range of edible species as a source of precursor proteins for antioxidant-active peptides. Food-derived antioxidant peptides reduce the production of reactive oxygen species, besides activating endogenous antioxidant defense systems in cellular and animal models. The intestinal absorption and metabolism of such peptides were elucidated by using cellular models. Protein hydrolysates (peptides) are promising ingredients with enhanced nutritional, functional, and organoleptic properties of foods, not only as a natural alternative to synthetic antioxidants.