In vitro H + /K + -ATPase Inhibition, Antiradical Effects of a Flavonoid-rich Fraction of Dissotis rotundifolia , and In silico PASS Prediction of its Isolated Compounds.

Background: Dissotis rotundifolia , commonly referred to as pink lady, has several medicinal uses including peptic ulcer. This study investigated the inhibitory effects of D. rotundifolia extract on H+ /K+ -ATPase and also assessed its antiradical activity. In silico study of some isolated compounds of this plant was also carried out to affirm the suspected binding properties of extract to H+ /K+ -ATPase enzyme.

Materials and Methods: D. rotundifolia whole plant extract was obtained after extraction process and then assessed for its ability to scavenge free radicals in four in vitro test models. Its ability to inhibit the activity of H+ /K+ -ATPase enzyme was also evaluated. Molecular docking was carried out on phytoconstituents, namely, vitexin, isovitexin, orientin, and isoorientin reported to be present in the whole plant extract.

Results: Data obtained indicated that D. rotundifolia extract (DRE) exhibits strong antioxidant activity. DRE also showed inhibitory effects on H+ /K+ -ATPase enzyme activity. Docking studies affirmed the in vitro binding effect of the extract to H+ /K+ -ATPase.

Conclusion: These findings suggest that the plant extract possess antioxidant and antipeptic ulcer activity.