Evaluation of Chemical Composition and Antileishmanial and Antituberculosis Activities of Essential Oils of Piper Species

Abstract

Essential oils from fresh Piperaceae leaves were obtained by hydrodistillation and analyzed by gas chromatography mass spectrometry (GC-MS), and a total of 68 components were identified. Principal components analysis results showed a chemical variability between species, with sesquiterpene compounds predominating in the majority of species analyzed. The composition of the essential oil of <i>Piper mosenii</i> was described for the first time. The cytotoxicity of the essential oils was evaluated in peritoneal macrophages and the oils of <i>P. rivinoides</i>, <i>P. arboretum</i>, and <i>P. aduncum</i> exhibited the highest values, with cytotoxic concentration at 50% (CC₅₀) > 200 µg/mL. Both <i>P. diospyrifolium</i> and <i>P. aduncum</i> displayed activity against <i>Leishmania amazonensis</i>, and were more selective for the parasite than for the macrophages, with a selectivity index (SI) of 2.35 and >5.52, respectively. These SI values were greater than the 1 for the standard drug pentamidine. The antileishmanial activity of the essential oils of <i>P. diospyrifolium</i> and <i>P. aduncum</i> was described for the first time. <i>P. rivinoides, P. cernuum</i>, and <i>P. diospyrifolium</i> displayed moderate activity against the <i>Mycobacterium tuberculosis</i> H₃₇Rv bacillus, with a minimum inhibitory concentration (MIC) of 125 µg/mL. These results are relevant and suggests their potential for therapeutic purposes. Nevertheless, further studies are required to explain the exact mechanism of action of these essential oils.