Hypouricemic Activity of Morinda Citrifolia (Noni) by Inhibition of Xanthine Oxidase for Treatment of Gout

Abstract

Gout is the most common form of inflammatory arthritis with a prevalence of 1-2% in developed countries. The major objectives in chronic gout management are to keep the serum uric acid level towards normal, prevent joint damage due to hyperuricemia and further occurr ence as well as to promote the dissolution of existing uric acid crystals as well as prevent new crystal formation. The present work is aimed at in-vitro xanthine oxidase inhibitory activity between the enzyme xanthine oxidase isolated from bovine milk and Morinda citrifolia fruit extract and comparing against standard drug allopurinol. Further the activity would be ascertained by molecular docking studies of phytoconstituents identified in Morinda citrifolia fruit extract on xanthine oxidase obtained from protein data bank using Molegro virtual docker. The IC50 values were found to be 178.6µg/ml and 99.6 µg/ml for Morinda citrifolia fruit extract and allopurinol respectively. From the docking studies based on the MolDock score, Bisdemethylpinoresinol, Asperulosidic acid, Aucubin, Rutin and Americanin A were found to be the most effective phytoconstituents to bind with the selected xanthine oxidase enzyme as compared to the standard drugs. In conclusion, the extract of Morinda citrifolia was found to possess appreciable hypouricemic activity where one or more of the phytoconstituents present in the extract may be responsible for the activity. Further in vivo studies are required to confirm the hypouricemic activity of Morinda citrifolia fruit extract.