Antimicrobial Activity of a Formulation of Libidibia ferrea L. against Microorganisms of the Dental Biofilm

This study aimed to evaluate the antimicrobial activity of the extract of Libidibia ferrea L. (228.022-INPA) and a mouthwash formulation against microorganisms of the dental biofilm. The extract of Libidibia ferrea L. was prepared and formulated with an alcohol-free mouthwash. The Minimum Inhibitory Concentration—MIC was determined by microdilution and cell viability was evaluated through fluorescence. The MICs for the extract were 4.375 μg/mL (Streptococcus mutans), 3.750 μg/mL (Streptococcus oralis), 4.375 μg/mL (Lactobacillus casei). In contrast, for the mouthwash, the MICs were 6.000 μg/mL (bacteriostatic against Streptococcus mutans and bactericidal against Streptococcus oralis). In 1.250 μg/mL of the extract, the number of viable cells measured by fluorescence tests was 16.47% and 14.12% for Streptococcus mutans and Lactobacillus casei, respectively. For the mouthwash (1.000 μg/mL), 20.60% of viable cells for Streptococcus mutans, and 9.60% for Lactobacillus casei were observed. It can be concluded that the extract and its mouthwash containig Libidibia ferrea L. showed antibacterial activity against microorganisms from the dental biofilm.