Abstract:

Objective：To investigate the effects of four active compounds of Geranium strictipes on the growth and acid production of
two kinds of cariogenic bacteria. Methods：Firstly, respectively determine the minimum inhibitory concentration (MIC) and the
minimum bactericidal concentration (MBC) of the active compounds of Geranium strictipes on two kinds of cariogenic bacteria. Then the
influence of active compounds of Geranium strictipes on the growth and acid production of two kinds of cariogenic bacteria were
determined. Results：The MIC of gallic acid, gallicin, catechins, ellagic acid on Streptococcus mutans respectively were 4.000, 4.000,
1.000, 1.000 g/L , while the MBC of gallic acid, gallicin, catechins, ellagic acid on Streptococcus mutans respectively were 8.000, 8.000,
2.000, 2.000 g/L ; The MIC of gallic acid, gallicin, catechins, ellagic acid on Actinomyces viscosus respectively were 4.000, 2.000,
0.500, 0.500 g/L , while the MBC of gallic acid, gallicin, catechins, ellagic acid on Actinomyces viscosus respectively were 8.000, 4.000,
1.000, 1.000 g/L. The active compounds of Geranium strictipes could inhibit the acid production of two kinds of cariogenic bacteria.
Conclusion：4 active compounds of Geranium strictipes can affect the growth and metabolism of two kinds of cariogenic bacteria，and
effectively inhibit the acid production.

Key words: Geranium strictipes, active compound, cariogenic bacteria, acid production