Phytochemical and enzyme inhibitory studies on indigenous medicinal plant Rhazya stricta.

A new triterpenoid 3alpha-hydroxy-ursane-5-ene (1) and a known steroid stigma sterol (2) have been isolated for the first time from the fruit of Rhazya stricta. The structures of these compounds were elucidated and identified by spectral studies. The crude ethanolic extract of R. stricta fruit has led to the determination of good results of antibacterial, lipoxygenase and acetylcholinesterase activities. In addition, we also reported the acetylcholinesterase activity of stigma sterol (2) isolated from this plant. Stigma sterol (2) was found to be an acetyl-cholinesterase inhibitor with IC(50) at a concentration of 644.0 +/- 11.75 microM. Eserine [(-)-physostigmine, IC(50) = 61 nM)] was used as a positive control.