Background:It has been widely exploredthat monoamine oxidases (MAOs) play a significant role in the activity of
the regulation central nervous system.Finding the potential natural lead compound with a greater affinity towards
MAO enzyme for the development of the natural candidate as the better neurological agent is our aim for this study.
Results:In the current study, we virtually screened the various categories of natural ligands by thein-silico approach
to achieve insight into theinteraction of natural compounds to the targeted protein. In thecase of MAO-B the
rhamnetin, quercetin, piperine, eugenol,and umbelliferone exhibited highest dock score -10.57, -9.938, -9.445, -
8.757and 7.821respectively. In the case of MAO-A umbelliferone, curcumin, caffeic acid, quercetin possessed dock
score -8.001, -7.941, -7.357, -6.658 respectively. Moreover, the top-ranked compounds with better docking score
were evaluated by in vitro MAO inhibitory assay. Compound umbelliferone was observed as the most active
hMAO-A inhibitor (IC50= 10.98±0.006 µM) and selectivity index of 0.607. In case of hMAO-B activity lead
compound rhamnetin has shown the value of 10.32±0.044 µM (SI value of 3.096) as compared with pargyline
(reference compound) with IC50 value of 20.04±0.095 µM.
Conclusions: These natural potential ligands have been found comparable to the standard drugs against MAO-A
and MAO-B, which may be treated as alead compound for the exploration of new drug compounds. The results of in
silico screening were in good correlation with in vitro hMAO inhibitory activity.