Abstract
This study aimed to test the effectiveness of ethyl gallate (EG) against S. mutans biofilm formation on solid surfaces (polystyrene, glass) and acidogenicity, and to examine the effect on expression of related genes. The biofilm that is formed by S. mutans bacteria was evaluated using colorimetric assay and optical profilometry, while the pH of the biofilm growth medium was measured with microelectrode. The expression of genes encoding glucan binding protein B (gbpB), glucosyltranferases B, -C, -D (gtfB, -C, -D) and F-ATPase (atpD, atpF) was assessed using a quantitative reverse transcription-polymerase chain reaction (RT-qPCR). It was revealed that all of the EG concentrations significantly suppressed S. mutans biofilm build-up on polystyrene and glass surfaces, and inhibited acidogenicity, in a dose-dependent manner, compared to the activity of untreated bacteria (p < 0.05). The highest concentration of EG (3.53 mM) reduced biofilm formation on polystyrene and glass surfaces by 68% and more than 91%, respectively, and prevented a decrease in pH levels by 95%. The RT-qPCR data demonstrate that the biofilm-producing bacteria treated with EG underwent significant gene expression changes involving the gtfC (a 98.6 increase in fold change), gtfB gene (a 47.5 increase in fold change) and the gbpB gene (a 13.8 increase in fold change). However, for the other genes tested (gtfD, atpD and atpF), the EG treatments did not produce significant expression change compared to the control. EG produced significant gene expression change in three genes—gtfC, gtfB, and gbpB; it has the capacity to inhibit S. mutans biofilm formation on solid surfaces (polystyrene, glass), as well as acidogenicity. Therefore, EG might be used as an antibiofilm and/or anticaries agent for oral formulations in order to reduce the prevalence of dental caries.
Highlights
The production of biofilm, known as dental plaque, is a virulent action of Streptococcus mutans on tooth surfaces [1,2] Five essential metabolic pathways are involved in cariogenic biofilm produced by S. mutans
We investigated the effects of ethyl gallate (EG) on the expression of six representative genes and report on changes in the expression of three important genes—gtfB, gtfC and atpD—which are essential for biofilm production and maintenance
Recent studies have investigated the effects of pure phenolic compounds and extracts on the studies have investigated the effects of pure phenolic compounds and extracts on the growthRecent of pathogenic bacteria; these compounds have mainly been derived from grape seed, which growth of pathogenic bacteria; these compounds have mainly been derived from grape seed, is considered a rich source of polyphenolic compounds [21,24] Gallic acid and ethyl gallate arewhich the is considered rich source compounds
Summary
The production of biofilm, known as dental plaque, is a virulent action of Streptococcus mutans on tooth surfaces [1,2] Five essential metabolic pathways are involved in cariogenic biofilm produced by S. mutans These pathways are regulated by several known genes; they include (1) for microbial adhesion, gbpB, sacB (ftf ), vicR and wapA, which are involved in sucrose-dependent adhesion, and spaP, involved in sucrose-independent adhesion [3,4,5]; (2) for biofilm formation, atlA, sacB (ftf ), SMU.609, vicR and wapA [6,7,8]; (3) for extracellular polysaccharide synthesis, gtfA, gtfB, gtfC, gtfD, sacB, (ftf ). These bacterial protein associations facilitate dental plaque production and dental caries induction
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
