Multi-Strain Probiotics: Synergy among Isolates Enhances Biological Activities

SIMPLE SUMMARY: Multi-strain probiotics are composed of more than one species or strains of bacteria and sometimes, including some fungal species with benefits to human and animals’ health. The mechanisms by which multi-strain probiotics exert their effects include cell–cell communications, interactions with the host tissues, and modulation of the immune systems. Multi-strain probiotics applications include alleviation of disease conditions, inhibition of pathogens, and restoration of the gastrointestinal microbiome. Despite all these benefits, the potential of using multi-strain probiotics is still not fully explored. ABSTRACT: The use of probiotics for health benefits is becoming popular because of the quest for safer products with protective and therapeutic effects against diseases and infectious agents. The emergence and spread of antimicrobial resistance among pathogens had prompted restrictions over the non-therapeutic use of antibiotics for prophylaxis and growth promotion, especially in animal husbandry. While single-strain probiotics are beneficial to health, multi-strain probiotics might be more helpful because of synergy and additive effects among the individual isolates. This article documents the mechanisms by which multi-strain probiotics exert their effects in managing infectious and non-infectious diseases, inhibiting antibiotic-resistant pathogens and health improvement. The administration of multi-strain probiotics was revealed to effectively alleviate bowel tract conditions, such as irritable bowel syndrome, inhibition of pathogens and modulation of the immune system and gut microbiota. Finally, while most of the current research focuses on comparing the effects of multi-strain and single-strain probiotics, there is a dearth of information on the molecular mechanisms of synergy among multi-strain probiotics isolates. This forms a basis for future research in the development of multi-strain probiotics for enhanced health benefits.