Chemical Compounds and Antimicrobial Assessment of the Essential oil from Lippia micromera Harvested in Cuba

Background/Objective: Anti-infective agents derived from plants have become important and favorable resources against diseases. In particular, essential oils have emerged as promising antimicrobial natural alternatives. The objective of this study is to evaluate the potentialities of Lippia micromera Schauer essential oil (EO-Lm) against a panel of bacteria, fungi, and protozoal parasites. Methods: Leaves of L. micromera were collected, the essential oils were obtained by hydrodistillation and analyzed by gas chromatography – mass spectrometry (GC-MS). Biological antimicrobial assays were performed and the cytotoxicity effect was determined on the MRC-5 cell line. Results: A total of 29 components (99.0% of the oil) were identified, which the main chemical compounds were thymol (36.0%), carvacrol (28.8%), p -cymene (13.2%), estragole (5.2%), γ-terpinene (4%), ( E )-β-caryophyllene (3.7%) and myrcene (1.6%). No activity was observed against Escherichia coli, Staphylococcus aureus , Candida albicans, Trypanosoma cruzi , or Leishmania infantum . However, against Plasmodium falciparum , Trypanosoma brucei , and Leishmania amazonensis EO-Lm displayed IC 50 values of 7.5, 51.8 and 26.2 μg/mL, respectively. In addition, no cytotoxicity was observed at the maximum working concentration (64 µg/mL) on the MRC-5 cell line. Conclusions: This study shows, for the first time, the chemical composition and the antimicrobial activity of EO-Lm harvested in Cuba. In particular, the relevant activity observed on P. falciparum should be corroborated in further experiments using animal models.