Antiulcer potential and molecular docking of flavonoids from Ocimum forskolei Benth., family Lamiaceae

The present study aimed to detect the bioactive metabolites from Ocimum forskolei aerial parts which are responsible for the antiulcer activity of the total ethanol extract (TEE) as well as different fractions (petroleum ether, dichloromethane, ethyl acetate and aqueous). Six flavonoids were isolated from the dichloromethane fraction which was the most potent; with an ulcer index value of 2.67 +/- 2.18*** and % inhibition of ulcer of 97.7%; following a bioassay-guided fractionation. The isolated flavonoids were subjected to molecular docking analysis in an attempt to explain their significant antiulcer potential, and the results revealed that salvitin followed by sideritiflavone were the main active ones acting against M3 and H-2 receptors, respectively. Moreover, a molecular dynamics simulation illustrated the formation of two persistent H-bonds between salvitin and the two amino acids of the active site (Asn507 and Asp147) formed in 42 and 65% of the frames, respectively.