Evaluation of the chemical composition and oral antimicrobial activity of the essential oil from the leaves of Pimenta pseudocaryophyllus (Gomes) landrum

Background: Pimenta pseudocaryophyllus is a native species from Brazil, whose leaves are used in the traditional culture as medicinal plants, being reported with antimicrobial and antifungal properties. Objectives: The aim of this study is to analyze and characterize the chemical composition of the essential oil (EO) extracted from the leaves of P. pseudocaryophyllus, as well as to evaluate its potential for antimicrobial activity against pathogenic bacteria inhabiting the human oral cavity. Materials and Methods: The extraction was performed by steam distillation and the chemical composition was analyzed using gas chromatography-mass spectrometry (GC-MS). The antimicrobial potential of the EO against Staphylococcus aureus, Pseudomonas aeruginosa, and Enterococcus faecalis was evaluated by agar well diffusion method. Different dilutions of the EO (10, 5, 2.5, 1.25, 0.625, 0.312, 0.156, 0.078, and 0.039%, v/v) were tested against the micro-organisms in disk diffusion tests to evaluate the minimum inhibitory concentration. Results: The extraction yielded 0.65% of EO in relation to fresh leaves of P. pseudocaryophyllus. GC-MS analysis identified eugenol, eucalyptol, and limonene as the major compounds of its. The material showed antimicrobial activity, especially against E. faecalis, with moderate activity against S. aureus, both at concentrations from 1.25% to 10%. Conclusion: The results suggested that this EO presents potential of activity against the oral micro-organisms here evaluated.