Antioxidant Activity of Piper Caninum and Cyclooxygenase-2 Inhibition by Methoxylated Flavones

Abstract

Background: The crude extracts and pure compounds isolated from Piper caninum was studied for their bioactivities. 
 Material and method: The present study was carried out with the following aims: (1) to quantify the total phenolic content and free radical scavenging activities of the crude extracts by Folin-Ciocalteu and 1,1-diphenyl-2-picrylhydrazyl free radical scavenging assay. (2) to determine the cyclooxygenase-2 inhibition activities of selected isolated compounds as assessed by molecular docking and in vitro cyclooxygenase-2 inhibition assay.
 Results: Methanolic extracts of Piper caninum exhibited the highest total phenolic content and free radical scavenging activities. All the pure compounds possessed significant cyclooxygenase-2 inhibition at physiological concentrations. 
 Conclusion: Based on our findings of the molecular docking and in vitro study, we therefore suggest that Piper caninum methoxylated flavones are potent inhibitors of cyclooxygenase-2 at physiological concentrations.