Abstract: Objective: To screen the Lactobacillus salivarius strains with probiotic potential from oral cavity of healthy volunteers, and to investigate its probiotic properties against oral diseases. Methods: Fifty healthy volunteers without oral disease were selected and their unstimulated salivas were collected for the selective bacteria culture. The Gram staining and the 16sr DNA sequencing technique were used to identify the Lactobacillus salivarius. To detect the antibacterial ability of the purified Lactobacillus salivarius, the inhibitory effect on the indicator bacteria, streptococcus mutans was observed. The targeted strain with antibacterial ability was screened and the antibacterial substance was then analyzed. Results: The w22a of Lactobacillus salivarius strain was selected. The effect of inhibiting streptococci mutans was increased with the increment of the concentration of the antibacterial substance. The antibacterial substance produced by the w22a was thermostabilized and sensitive to protease and had broad-spectrum antibacterial ability. Conclusion: The w22a of Lactobacillus salivarius strain might be one kind of potential probiotic of oral cavity.

Key words: Saliva, Lactobacillus salivarius, Probiotic properties, Bactericidal substance