Anti-quorum Sensing of Terminalia catappa and Murraya koenigii Against Streptococcus mutans

Introduction Dental biofilm constitutes micro-organisms existing in an intercellular matrix containing organic and inorganic materials derived from saliva, gingival crevicular fluid, and bacterial products. Dental plaque biofilm inhibition by certain herbs and medicinal plants has been used as a treatment modality for the prevention of white spot lesions in orthodontic subjects. The aim of this study was to evaluate the anti-quorum sensing and anti-biofilm activity of Terminalia catappa and Murraya koenigiiagainst Streptococcus mutans. Materials and methods Samples of dental plaque were taken from patients receiving orthodontic care. The colonies of the S. mutans were isolated and biochemical characterization was done. Leaf extracts of Terminalia catappa and Murraya koenigii were used in the study. Methanolic extracts were subjected to evaluation of minimum inhibitory concentration (MIC) using the broth microdilution (two-fold) method and anti-biofilm activity using the crystal violet staining method. Results  The MIC of methanol leaf extracts of Murraya koenigii against S. mutans was noted at 0.62 mg/ml and Terminalia catappa at 1.25 mg/ml. At the lowest concentration of 0.03 mg and 0.01 mg methanol extract of Murraya koenigii had remarkably inhibited biofilm formation of 57.6% and 43.6% against S. mutans, respectively. Terminalia catappa leaf extracts did not show any anti-biofilm activity when the organisms were grown in the presence of S. mutans. Conclusion  Both Murraya koenigii and Terminalia catappa had antibacterial effects against S. mutans and Murray koenigii remarkably inhibited biofilm formation by S. mutans.