The Role of Quorum Sensing Mechanism in the Functional Properties of Lactic Acid Bacteria

Lactic acid bacteria (LAB) are non-spore-forming, non-respiring, Gram-positive cocci or rods that produce lactic acid through carbohydrate fermentation. They are widely used in food and dairy production as probiotics, biofertilizers, and as sources of industrially valuable exopolysaccharides. Growing evidence indicates that many of these functional properties are regulated by quorum sensing (QS), a cell–cell communication mechanism that coordinates bacterial behavior in response to population density. This review summarizes current knowledge on the role of QS in regulating key physiological and functional traits of LAB, including biofilm formation, stress adaptation, metabolite production, and host interactions. Additionally, it highlights the ability of LAB-derived molecules to interfere with QS systems of pathogenic bacteria, contributing to pathogen control. Overall, this review emphasizes QS as a key regulatory mechanism underlying the technological and probiotic potential of LAB, with important implications for food, health, and biotechnological applications.