Effect of lariciresinol-4-beta-D-glucopyranoside on the growth and biofilm formation of Streptococcus mutans

Abstract:

[Objective] To study the effects of lariciresinol-4-beta-D-glucopyranoside on the growth and biofilm formation of Streptococcus mutans.[Methods] MTT[3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay was used to analyze the effects of lariciresinol-4-beta-D-glucopyranoside on the biofilm formation of Streptococcus mutans; oxygen sensitivity test was used to detect the effects of lariciresinol-4-beta-D-glucopyranoside on oxygen sensitivity of S. mutans; Realtime PCR was used to detect gene expression level. The cytotoxic of lariciresinol-4-beta-D-glucopyranoside was analyzed by using human monocytes. [Results] We found that lariciresinol-4-β-D-glucopyranoside could significantly inhibit the growth of S. mutans, and also suppress the biofilm formation of S. mutans in a concentration-dependent manner. And in lariciresinol-4-β-D-glucopyranoside-treated biofilms, we also found that the mRNA expression levels of brpA (transcriptional regulator), recA (recombinase A), nth (endonuclease III), luxS (S-ribosylhomocysteinase), ffh (fifty four homologue), smx (sulfamethoxazole), gtfB (glucosyltransferase-I) and gtfC (glucosyltransferase-SI) were all decreased. We further revealed that lariciresinol-4-β-D-glucopyranoside (50 μg/mL) had no effect on the growth and LDH activity of human monocytes. [Conclusion] Our findings suggested that lariciresinol-4-β-D-glucopyranoside inhibited the biofilm formation of S. mutans, and the decrease of luxS, brpA, ffh, recA, nth, smx, gtfB and gtfC might contribute to the antibacterial effects of lariciresinol-4-β-D-glucopyranoside.