Phytochemical screening, antinociceptive and anti-inflammatory effects of the essential oil of Myrcia pubiflora in mice

This report aimed to investigate the chemical composition and possible antinociceptive and anti-inflammatory effects of the essential oil from fresh leaves of Myrcia pubiflora DC., Myrtaceae (EOMP), through different experimental tests. The essential oil of M. pubiflora (EOMP) was obtained by hydrodistillation, analyzed by GC-MS, and tested at doses of 25, 50, and 100 mg/kg (i. p.) in three different tests of nociception (acetic acid-induced writhing test, formalin test, and hot plate test) and one test of inflammation (leukocyte migration to the peritoneal cavity) in order to evaluate the motor activity in mice treated with EOMP. The major component of EOMP was caryophyllene oxide (22.16%). This oil significantly reduced the number of writhes in an acetic acid test and the time spent licking the paw at the second phase of the formalin test. Furthermore, EOMP inhibited the carrageenan-induced leukocyte migration to the peritoneal cavity. However, administration of EOMP did not alter reaction time in the hot plate test, and did not affect the motor coordination test. These results indicate antinociceptive and anti-inflammatory properties of EOMP probably mediated via inhibition of inflammatory mediator synthesis or other peripheral pathway.