Determination of antibacterial activity and metabolite profile of Ruta graveolens against Streptococcus mutans and Streptococcus sobrinus

J Lab Physicians. 2018 Jul-Sep;10(3):320-325. doi: 10.4103/JLP.JLP_160_17.

Abstract

Background: Ruta graveolens is one of the most used phytomedicines. To date, there is no report of determining the bioactivity of R. graveolens against cariogenic causing bacteria (Streptococcus mutans and Streptococcus sobrinus).

Objective: The objective of the present study was to determine the antibacterial activity and metabolite profile of R. graveolens against S. mutans and S. sobrinus.

Materials and methods: R. graveolens plant material was collected and processed in the month of February. The plant material was extracted by Soxhlet apparatus using methanol solvent. Two strains of S. mutans and two strains of S. sobrinus were isolated from dental caries-active participants and cultured on mitis salivarius-bacitracin agar. The antibacterial susceptibility testing of methanolic extract of R. graveolens was performed by disc diffusion method. The metabolite profile of the plant extract was determined using electrospray ionization-tandem mass spectrometry.

Results: The methanolic extract of R. graveolens showed a promising antibacterial activity against S. mutans and S. sobrinus. Two compounds named γ-fagarine and kokusaginine were identified from the methanolic extract of R. graveolens.

Conclusion: The study concluded that R. graveolens contains significant antibacterial activity. However, further investigations are suggested to understand the anticaries properties of these pure compounds.

Keywords: anticariogenic; dental caries; electrospray ionization-tandem mass spectrometry; kokusaginine; mutans streptococci; γ-fagarine.