Impact of food-derived bioactive peptides on gut function and health

The gastrointestinal tract (GIT) is the largest interface between our body and the environment. It is an organ system extending from the mouth to the anus and functions for food intake, digestion, transport and absorption of nutrients, meanwhile providing protection from environmental factors, like toxins, antigens, and pathogens. Diet is one of the leading factors modulating the function of the GIT. Bioactive peptides presenting naturally in food or derived from food proteins during digestion or processing have been revealed multifunctional in diverse biological processes, including maintaining gut health and function. This review summarizes the available evidence regarding the effects of food-derived bioactive peptides on gut function and health. Findings and insights from studies based on in vitro and animal models are discussed. The gastrointestinal mucosa maintains a delicate balance between immune tolerance to nutrients and harmful components, which is crucial for the digestive system's normal functions. Dietary bioactive peptides positively impact gastrointestinal homeostasis by modulating the barrier function, immune responses, and gut microbiota. However, there is limited clinical evidence on the safety and efficacy of bioactive peptides, much less on the applications of dietary peptides for the treatment or prevention of diseases related to the GIT. Further study is warranted to establish the applications of bioactive peptides in regulating gut health and function.

Development of Antioxidant and Antihypertensive Properties during Growth of Lactobacillus helveticus, Lactobacillus rhamnosus and Lactobacillus reuteri on Cow's Milk: Fermentation and Peptidomics Study

Bioactive peptides derived from milk proteins are an active research area. Exhibiting numerous positive physiological effects on digestive, cardiovascular, immune and nervous systems, these peptides thought to be one of the most promising ingredients for functional food. Generally, these peptides are inactive within the parent proteins and can be liberated during milk fermentation by the specific proteolytic systems of various Lactobacillus spp. Here we present the study of milk fermentation by Lactobacillus helveticus NK1, Lactobacillus rhamnosus F and Lactobacillus reuteri LR1 strains. It was demonstrated that the antioxidant activity of the milk fermented by these strains concomitantly increased with the strains’ proteolytic activity. For the angiotensin I-converting enzyme (ACE) inhibitory activity, the same tendency was not observed. Although the proteolytic activity of L. helveticus NK1 was two times higher than that of L. rhamnosus F, the milk fermented by these strains showed comparable ACE inhibition. The analysis of the peptide profiles of the fermented milk samples allowed us to hypothesize that some previously unreported peptides can be produced by L. rhamnosus F. In addition, it was demonstrated that these potential ACE-inhibiting peptides originated from the C-terminus of α_S2-casein.