Minireview Kefir as a source of antimicrobial compounds against bacterial pathogens

Milk kefir is a fermented drink traditionally consumed by humans for approximately 3,000 years, shaped by a bacterial and yeast consortium, with probiotic capacity. During the fermentation process, the microbial community synthesizes a broad-spectrum of compounds working synergically, as organic acids, bacteriocins, exopolysaccharides, and other bioactive metabolites that inhibit diverse bacterial or fungal pathogens like Salmonella typhimurium, Pseudomonas aeruginosa or Fusarium oxysporum . These compounds are mainly produced by the kefir’s lactic acid bacteria and modifies the environment and disrupt pathogen cell membranes or promote pores into the cell walls in pathogenic bacteria, among other mechanisms. Therefore, in this review, we explore the antimicrobial bioactive compounds produced by the kefir bacteria and associated yeast, such as organic acids, bacteriocins, bioactive peptides, and exopolysaccharides, among others, not only acting as individual molecules but also as results of a complex combination of metabolic products.