Current knowledge on the polymicrobial interaction and biofilm between Saccharomyces and Lactobacillaceae: regulatory mechanisms and applications.

The family Lactobacillaceae plays a crucial role in food fermentation and probiotic applications, and exhibiting metabolic versatility and adaptability to diverse nutrient-rich environments. They are abundant in nutrient-rich environments like fermented food, vegetables, and the vaginal and gastrointestinal tracts of animals, where they metabolize carbohydrates to produce lactic acids. They also produce bioactive compounds and exhibit anti-inflammatory, antibacterial, and antifungal properties. Saccharomyces yeasts are also widely applied in food, medicine, and biofuel industries. Some species, such as S. boulardii, are recognized for their probiotic benefits, particularly in promoting gut health and alleviating intestinal disorders. This review focuses on the polymicrobial interactions between Lactobacillaceae and Saccharomyces species, highlighting their synergistic roles in improving fermentation efficiency, product quality, and microbial stability through mechanisms such as biofilm formation, metabolic exchange, and nutrient sharing. We also discuss competitive interactions observed in certain systems, such as sugarcane fermentation, which demonstrate the complexity of microbial ecology and the need for precise microbial management strategies. By synthesizing current research, this review aims to provide a comprehensive understanding of how microbial interactions influence fermentation outcomes, and to identify existing knowledge gaps and future directions for optimizing industrial applications.