Antioxidant Action and Anti-Inflammatory and Antinociceptive Activities of Fruit Peels: Possible Involvement of Opioidergic System.

This work evaluated the antioxidant properties and antinociceptive and anti-inflammatory effects of extracts obtained from fruit peels of (H. West ex Willd.) O. Berg (Myrtaceae). This plant is popularly known in Brazil as or . Different extracts were submitted to comparative analysis to determine the content of selected phytochemical classes (levels of total phenols, flavonoids, and monomeric anthocyanins) and the antioxidant potentials. The extract with higher potential was selected for evaluation of its antinociceptive and anti-inflammatory action. Finally, the chemical characterization of this extract was performed by high-performance liquid chromatography (HPLC). MfAE (extract obtained using acetone as solvent) showed the higher levels of phenols (296 mg GAE/g) and anthocyanins contents (35.65 mg Cy-3-glcE/g) that were associated with higher antioxidant activity. MfAE also exhibited anti-inflammatory and analgesic propertiers. This fraction inhibited the inflammatory and neurogenic phases of pain, and this effect was reversed by naloxone (suggesting the involvement of opioidergic system). MfAE reduced the abdominal contortions induced by acetic acid. The HPLC analysis revealed the presence of gallic acid (and its derivatives) and ellagic acid. Taken together, these data support the use of fruit peels for development of functional foods and nutraceutics.