Antimicrobial effects of terpinen-4-ol against oral pathogens and its capacity for the modulation of gene expression

Abstract

This study evaluated the antibacterial activity of terpinen-4-ol against <i>Streptococcus mutans</i> and <i>Lactobacillus acidophilus</i> and its influence on <i>gbpA</i> (<i>S. mutans</i>) and <i>slpA</i> (<i>L. acidophilus</i>) gene expression. As measured by XTT assay, the concentrations of terpinen-4-ol that effectively inhibited the biofilm were 0.24% and 0.95% for <i>S. mutans</i> and <i>L. acidophilus</i>, respectively. Confocal microscopy revealed the presence of a biofilm attached to the enamel and dentin block surfaces with significant terpinen-4-ol effects against these microorganisms. The expression of the <i>gbpA</i> and <i>slpA</i> genes involved in adherence and biofilm formation was investigated using RT-PCR. Expression of these genes decreased after 15 min with 0.24% and 0.95% terpinen-4-ol in <i>S. mutans</i> and <i>L. acidophilus</i>, respectively. These findings demonstrate the antimicrobial activity of terpinen-4-ol and its ability to modulate the expression of <i>gbpA</i> and <i>slpA</i> genes, emphasizing the therapeutic capacity of terpinen-4-ol as an alternative to inhibit adherence in biofilm.