Evaluation of the antibacterial effects of aqueous and ethanolic leaf extracts of () on Streptococcus mutans and Streptococcus sobrinus.

INTRODUCTION

The plant from the family of has many uses in traditional medicine. The aim of the current study was to determine the effects of the aqueous and ethanolic extracts of on and , which cause tooth decay.

METHODS

This 2016 study was performed on standardized strains of PTCC1683 and PTCC1601 and clinical isolates. Twenty clinical samples were obtained from the dental caries of children admitted to the pediatric ward at the Faculty of Dentistry of Babol University of Medical Sciences (Babol, Iran). The aqueous and ethanolic extracts of leaves were prepared in several concentrations ranging from 625-20,000 μg/ml. These concentrations of the extracts were applied to the bacteria by disk diffusion, agar well diffusion, and macrotube dilution. The antibacterial effects of amoxicillin and chlorhexidine digluconate 0.2% (CHX) were also carried out. Data were analyzed by SPSS version 18 software using independent-samples t-test.

RESULTS

was successfully isolated from nine out of 20 (45%) specimens. Of the 9 positive samples cultured, 8 (88.8%) were S. mutans and 1 was S. sobrinus (11.2%). No inhibitory zone was observed around the disks and wells containing all concentrations of extracts. The minimum concentrations for inhibition of growth (MIC) resulted in turbidity in all tubes and were negative except for the control tubes. Inhibition zones were observed for amoxicillin and CHX disks ( < 0.001).

CONCLUSION

This study found that all studied bacteria were resistant to both types of the extracts; therefore, they are not a suggested replacement for chemical agents in mouthwash. It also shown that CHX is less effective than amoxicillin.