Molecular docking, isolation and biological evaluation of Rhizophora mucronata flavonoids as anti-nociceptive agents

The anti-nociceptive effect of Rhizophora mucronata was evaluated on chemically and thermally induced nociception in mice. Albino mice received a dose of 10, 15, 20, or 25 mg/kg of alkaline chloroform fraction (Alk-CF) of R. mucronata by oral administration. Compared with controls, Alk-CF decreased the writhing numbers (P < 0.01) in a dose-dependent manner. Further, we determined that Alk-CF contained, a potent compared to control, also potent anti-nociceptive agent that acted via opioid receptors and using HPLC, identified this compound as luteolin. Docking simulation demonstrated that luteolin interacted strongly with cyclooxygenase, forming a number of specific hydrogen bonds. This study identified peripheral and central anti-nociceptive activities of R. mucronata that involve opioid receptor, and in which the active compound is luteolin as a source of new anti-nociceptive agent.