FIG 5.

Effects of pH on H₂O₂ production in various oral streptococci. (A) H₂O₂ production of S. sanguinis 133-79 and S. parasanguinis at pH 7 and pH 6. (B) H₂O₂ production of S. gordonii JM1 and S. dentisani at pH 7 and pH 6. (C) Lactic acid levels in S. sanguinis 133-79, S. parasanguinis, S. gordonii JM1, and S. dentisani at pH 7 and pH 6. (D) CFU quantification of S. sanguinis 133-79, S. parasanguinis, S. gordonii JM1, and S. dentisani at pH 6 and pH 5.5 after overnight growth. All data were obtained at least three separate times. *, significant difference (P < 0.05).