Fig. 1

Biological properties of the clinical isolates from SECC group and CF group. Clinical strains of S. mutans were subjected to anaerobic culture at 37 °C to form a 24 h biofilm. The biomass of the biofilm was evaluated by crystal violet (CV) staining method. The result was showed in a The acidogenicity assay was used to evaluate the ability of acid-producing of the clinical strains. The reduction of the pH values of the medium was used to represent the ability of acid production of the strains. The result was showed in b The aciduricity assay was used to explore the ability of aciduricity of the S. mutans clinical strains through the percentage of bacterial growth, the result was showed in c The assay of the two groups were repeated three times, and the data represented the mean ± standard deviation of three independent experiments. * indicates that the data is statistically different (* P < 0.05, ** P < 0.01, ***P < 0.001)