Abstract
Objective: To analyze the antibacterial activity of hydroalcoholic extracts of mastruz leaves, coité and both associated, in strains of Streptococcus mutans, and Staphylococcus aureus resistant and sensitive to methicillin (MRSA and MSSA). Methods: This is an in vitro research, with the antibacterial activity determined by the technique of diffusion in wells, where Petri dishes with the seeded bacteria received 100 µL of the extracts for later measurement of the inhibition halos. Chlorhexidine digluconate 0.12% and 2% was used as a positive control. The Mann Whitney test was used to verify antimicrobial difference between each extract and chlorhexidine for each type of bacteria. Results: The coité showed significant antibacterial activity on the bacteria S. aureus (MRSA and MSSA) and S. mutans, with an effect superior to 0.12% chlorhexidine digluconate for MSSA (p = 0.043) and equivalent for MRSA (p = 0.197) and S. mutans (p = 0.121). The mastruz did not develop antibacterial activity on the strains tested. Conclusion: Coité showed antibacterial effect equivalent or superior to 0.12% chlorhexidine in the 3 strains tested, showing itself as a viable alternative to natural antimicrobial, of low cost and of easy access by the population.