Recent Advances in the Understanding of Stress Resistance Mechanisms in Probiotics: Relevance for the Design of Functional Food Systems

BUSTOS, ANA YANINA; TARANTO, MARÍA PÍA; GEREZ, CARLA LUCIANA; AGRIOPOULOU, SOFIA; SMAOUI, SLIM; VARZAKAS, THEODOROS; ENSHASY, HESHAM ALI EL

Probiotics and Antimicrobial Proteins

Springer

Año: 2024 vol. 17 p. 138 - 158

1867-1306

In recent years, more and more scientific community, food producers, and food industry show increased interest in functionalfoods containing probiotics, which is a big challenge. The consumption of probiotics in the context of a balanced diet throughthe consumption of functional foods or through the intake of pharmaceutical preparations has proven to contribute to theimprovement of human health, even contributing to the prevention of diseases. In order for probiotics to be considered suitablefor consumption, they must contain a minimum concentration of viable cells, namely, at least 107colony forming unitsof beneficial microbes per gram. Ensuring the viability of bacterial cells until the moment of consumption is the overridingpriority of functional probiotic food manufacturers. Probiotic bacteria are subject to stress conditions not only during foodmanufacturing but also during gastrointestinal passage, which limit or even compromise their functionality. This paper firstexamines all the stressful conditions faced by probiotic cells in their production stages and related to the conditions presentin the bioreactor fermentation and drying processes as well as factors related to the food matrix and storage. The stresssituations faced by probiotic microorganisms during the gastrointestinal transit especially during stomach and intestinalresidence are also analyzed. In order to understand the adaptation mechanisms of probiotic bacteria to gastrointestinal stress,intrinsic and adaptive mechanisms identified in probiotic strains in response to acid stress and to bile and bile acid stress areanalyzed. In addition, improvement strategies for multiple stress tolerance of lactic acid bacteria through directions dealingwith stress, accumulation of metabolites, use of protectants, and regulation of technological parameters are examined.Finally, the definition of postbiotics, inanimate microorganisms and/or their components conferring health benefits, is alsointroduced. Postbiotics include cell lysates, enzymes, and cell wall fragments derived from probiotic bacteria and may representan alternative to the use of probiotics, when they do not tolerate stressful conditions.