Abstract
Background: From the ancient times, medicinal herbs have been regarded as efficient resources for the treatment of diseases. Among the
diseases that can be treated by medicinal herbs, infectious diseases like oral ones are of notable importance.
Objectives: The aim of this study was to evaluate the antibacterial effects of Ferula assa-foetida L (F. assa-foetida L.) and Quercus infectoria
Olivier (Q. infectoria Olivier) aqueous and ethanolic extracts on Streptococcus mutans (S. mutans) and Streptococcus sanguis (S. sanguis).
Materials and Methods: The studied plants were F. assa-foetida L. and Q infectoria Olivier. Their extracts with different concentrations of
100, 50, 25, 12.5, 6.25, and 3.125 mg/mL were prepared in culture medium, with well diffusion method, and, for control, their antibacterial
effects were compared with chlorhexidine. For each extract, the antibacterial ability was determined based on the created inhibition zone
diameter in the microbial culture medium.
Results: The aqueous and ethanolic extract of F. assa-foetida L. lacked the inhibitory effect against the growth of S. mutans and S. sanguis
bacteria. There was a significant difference among the inhibitory zones created by dissimilar concentrations of Q. infectoria (P = 0.025).
Also, the aqueous and ethanolic extracts’ minimum inhibitory concentration (MIC) for S. mutans bacterium was calculated to be 12.5 mg/
mL, while its value for S. sanguis bacterium was 6.25 mg/mL.
Conclusions: The results of our study, regarding the observed effects based on differences in concentrations, suggest that further and
more comprehensive studies should be undertaken to determine the appropriate concentration for obtaining the effect of the extract of
F. assa-foetida L. and Q infectoria Olivier on S. mutans and S. sanguis