Abstract: Lactic acid bacteria (LAB) are a group of gram-positive bacteria without spores that can ferment carbohydrates to produce acids. As an important member of the probiotic family, LAB have a variety of probiotic functions, such as regulating intestinal florae balance, participating in immune responses and inhibiting the growth and reproduction of intestinal pathogenic bacteria. The prerequisite for the continuous performance of these probiotics is that they can colonize the intestine, but so far the underlying mechanism retains unclear. The factors (adhesion capacity, mobility, lactic acid secretion, interaction with the intestinal flora, the host’s genes and physical factors, tolerance to gastric acid and cholate, and the diet) interfering with LAB colonization in the intestine are reviewed in this article. Meanwhile, it also outlines the methods used to research LAB colonization in the intestine (plate counting, fluorescent labeling, polymerase chain reaction and new nano-materials). With the aim of providing a deeper understanding of LAB colonization of the intestinal tract, this review will provide a reference for further uncovering the underlying mechanism.

Key words: lactic acid bacteria; intestinal colonization; colonization factors; adhesion models; quantitative methods; in vivo tracing