1Associate Professor, Department of Orthodontics, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
2Dentist, Private Practice, Tehran, Iran
3Assistant Professor, Department of Oral Medicine, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
4Maryam Torshabi, Pharm.D, Ph.D of pharmaceutical Biotechnology, Assisstant proferssor, department of den tal biomaterial, dental school, shahid beheshti university of medical sciences, telfax:02122173754
Aims: In our previous studies, we showed the inhibitory effects of Punica granatum L. flower and Rhus coriaria L. fruit water extracts on dental plaque accumulation by several bacteria, especially Streptococcus mutans (S. mutans), on orthodontic wire by in vitro assays. In this study, the anti-cariogenic properties of the extracts were evaluated by assessing their effects on expression of glycosyltransferase (gtf) genes, which are responsible for initial biofilm formation by S. mutans.
Methods: In this study, the effect of herbal extracts on expression of gtfB, C (encoding enzymes that produce water-insoluble glucans) and D (encoding enzymes that produce water-soluble glucans) genes in S. mutans growing in planktonic state was evaluated quantitatively by real-time polymerase chain reaction (PCR) method.
Results: The minimum biofilm inhibitory concentration (MBIC) of understudied herbal water extracts significantly suppressed gtfB, C and D gene expression by 85.3 ± 7.5%, 33.3 ± 6.4% and 25 ± 14%, respectively for Punica granatum L. extract and 73.4 ± 7.3%, 93.8 ± 2.7% and 59.3 ± 9.8%, respectively for Rhus coriaria L. extract compared to the non-treated control group (P<0.05). Also, the real-rime PCR showed that the inhibitory effect of Rhus coriaria L. extract on gtfC and D was significantly greater (10.8 and 1.8 fold, respectively) than that of Punica granatum L. extract. Conclusions: These ﬁndings suggest that Punica granatum L. and especially Rhus coriaria L. maybe used as novel, natural antiplaque agents since they inhibit speciﬁc genes associated with bacterial bioﬁlm formation without necessarily affecting the growth of oral bacteria.