Bacterial extracellular vesicles: An emerging postbiotic.

Our growing appreciation of the functional significance of the human microbiota in health and disease has triggered a marked interest in bacterial-derived extracellular vesicles (bEVs). In recent years, bEVs have been found to offer physiological benefits to the host by providing diverse bioactivity. Following the recent definition of postbiotics as a preparation of inanimate microorganisms and/or their components that confer a health benefit on the host, bEVs could serve as potential novel postbiotics. This review provides an overview of the biology of bEVs, evidence for their health benefits, and possible molecular pathways involved in their health-promoting effects, as well as perspectives for applications in foods and pharmaceuticals. Preclinical evidence has shown that bEVs confer diverse health-promoting functions to the intestinal local and extraintestinal organs, including immunomodulatory, anti-obesogenic, angiogenesis and osteogenesis, barrier tightening and cancer cell apoptosis. Although the exact mechanisms have not been entirely elucidated, this evidence demonstrates that bEVs may contribute to host health by regulating specific physiological functions and appear to be promising candidates as novel postbiotics. • Bacterial extracellular vesicles (bEVs) are nano-sized particles that contain various biomolecules from parental bacteria. • Bacteria use bEVs to deliver biomolecules into host cells that can modulate host signaling pathways and cell processes. • bEVs are recognized to be one of the key underlying mechanisms behind beneficial effects of many bacteria. • bEVs may be the postbiotics of the future with potential health benefits. • The safety, stability and scalability of bEVs need to be addressed before it can be used in products. [ABSTRACT FROM AUTHOR]