1. Exploring the antimicrobial efficacy of tea tree essential oil and chitosan against oral pathogens to overcome antimicrobial resistance.
- Author
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Oliveira MS, Paula MSA, Cardoso MM, Silva NP, Tavares LCD, Gomes TV, Porto DL, Aragão CFS, Fabri RL, Tavares GD, and Apolônio ACM
- Subjects
- Gas Chromatography-Mass Spectrometry, Mouth microbiology, Humans, Terpenes pharmacology, Cell Survival drug effects, Aggregatibacter actinomycetemcomitans drug effects, Bacteria drug effects, Drug Resistance, Bacterial, Oils, Volatile pharmacology, Oils, Volatile chemistry, Anti-Infective Agents pharmacology, Tea Tree Oil pharmacology, Tea Tree Oil chemistry, Chitosan pharmacology, Biofilms drug effects, Biofilms growth & development, Microbial Sensitivity Tests, Anti-Bacterial Agents pharmacology
- Abstract
Background: Considering that antimicrobial resistance among oral pathogens is a significant concern in dental practice, with broader implications for overall health due to the oral microbiota serving as a reservoir for antibiotic resistance genes (ARGs), research into natural products is crucial for addressing this issue., Objective: This study aimed to evaluate tea tree oil (TTO) and chitosan (CH) performance against oral pathogens, including mixed-species biofilm, and its effects on bacteria growth, in addition to chemical characterization and cytotoxicity of TTO., Methods: Tea Tree Oil and low molecular weight chitosan were used in this study. The chemical composition of TTO was analyzed using gas chromatography coupled with mass spectrometry (GC-MS). To evaluate TTO's antimicrobial properties, time-kill and cell viability assays were conducted. Additionally, minimum inhibitory concentration (MIC), minimum microbiocidal concentration (MMC), checkerboard, and biofilm assays were performed using TTO and CH alone and in combination., Results: TTO chromatography peaks found consistent with the standard ISO4730:2017 and literature. TTO and CH exhibited inhibitory activity against all tested microorganisms. The predominantly microbiostatic activity of TTO is probably related to terpinen-4-ol associated with terpinene. The oil at MIC value was able to delay the log phase of Aggregatibacter actinomycetemcomitans growth. Fibroblasts (L929) viability remained above 70 % during 24 h for TTO concentrations ranging from 0.5 to 0.0625 mg/ml. TTO-CH combination showed a synergistic activity (FIC = 0.5) against A. actinomycetemcomitans and Streptococcus sanguinis, at a concentration of 0,25MIC for both species. The compounds at MIC concentration inhibited both monospecies and mixed-species biofilms studied bacteria to the same extent as the azithromycin control., Conclusion: TTO and CH demonstrated efficacy in combating oral pathogens and TTO-CH combination offers a promising approach to confront microbial resistance in the oral environment., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ana Carolina Morais Apolonio reports financial support was provided by Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG- APQ-01165-22). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
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