Abstract
Phytochemical investigation of Anisacanthus virgularis aerial parts resulted in isolation of a new iridoid glucoside named as 7-O-p-trans-coumaroyl caryoptoside (1) together with two known iridoids, caryoptoside (2) and lamalbide (3). Their structures were elucidated by spectroscopic methods including 1D and 2D-NMR techniques. The isolated compounds together with the MeOH and aqueous extracts of the plant were investigated for their antiamoebic activity in vitro. The micro dilution technique was employed to investigate antiamoebic activity against Entamoeba histolytica HM1-SS strain. The results showed that the MeOH extract had good inhibition along 72 hours followed by the aqueous extract at concentration of 15 mg/mL. The compounds 1-3 showed good inhibition percent 72.2%, 50.1% and 52.6% after 24 hours of incubation at a concentration of 4 mu M, compared to the standard antiamoebic drug, Metronidazole.