Chemical Composition and Antinociceptive Properties of Hyeronima alchorneoides Leaves

AbstractIn the current study, we investigated the analgesic activity of a crude methanol extract and some fractions obtained from Hyeronima alchorneoides Allemao leaves and analyzed its phytochemical profile to determine active principles. All the fractions exhibited analgesic properties using the writhing test in mice, but the hexane fraction was the most active, causing 96.4 ± 1.0% inhibition at 10 mg/kg. Three compounds were isolated and identified based on their spectral data: simiarenol (1), β.-sitosterol (2), and amentoflavone (3). Compound 1, a rare terpene isolated for the first time from the family Euphorbiaceae, presented a calculated ID50 value of 18.87 (14.6–24.4)µmol/kg with the writhing test, being about 8-fold more active than two known analgesic and anti-inflammatory drugs (aspirin and dipyrone). In the formalin test, it was particularly active against the second phase, with inhibition of 59.5 ± 9%, suggesting a peripheral activity. In the capsaicin and glutamate tests, it showed inhibitio...