Comparative evaluation of anti-biofilm and anti- adherence potential of plant extracts against Streptococcus mutans: A therapeutic approach for oral health

Abstract

Dental caries predominantly attributed to the cariogenic nature of Streptococcus mutans, continue to pose a substantial global challenge to oral health. In response to this challenge, this study aimed to evaluate the effectiveness of leaf extracts (LEs) and essential oils (EOs) derived from different medicinal plants in inhibiting the growth of Streptococcus mutans biofilm. In vitro and in silico approaches were employed to identify active compounds and assess their inhibitory effects on S. mutans. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were measured to determine the anti-biofilm and anti-adherence activity against S. mutans. Biofilm viability (CFU/mL) and extracellular polymeric substance (EPS) concentration were quantified. GC-MS analysis was utilized to identify active compounds in the most effective plant extracts exhibiting anti-S. mutans activity. A high-throughput screening focused on the interaction between these compounds and the target enzyme SortaseA (SrtA) using molecular docking was performed. Results indicated that Cymbopogon citratus displayed the highest efficacy in reducing S. mutans biofilm formation and adhesion activity, achieving 90 % inhibition at an MIC value of 12 μg/mL. Among the 12 bioactive compounds identified, trans-Carvyl acetate exhibited the lowest binding energy with SrtA (-6.0 Kcal/mole). Trans-Carvyl acetate also displayed favorable pharmacokinetic properties. This study provides novel insights into the anti-S. mutans properties of C. citratus and suggests its potential as a therapeutic approach for oral health. Further research is needed to explore the combined effect of plant extracts for enhanced protection against dental caries.