Sedative and anxiolytic effects of different fractions of the Commelina benghalensis Linn

The present study was designed to investigate sedative and anxiolytic properties of the four different fractions (chloroform, pet ether, n-butanol and hydromethanol soluble fractions, coded as CFCB, PECB, NBCB and HMCB, respectively) of the aerial parts of Commelina benghalensis using rodent behavioral models, such as hole cross, open field and thiopental sodium induced sleeping time tests for sedative property and elevated plus-maze (EPM) test for anxiolytic potential, respectively. All fractions, at the doses of 200 mg/kg, p.o. and 400 mg/kg, p.o., displayed dose dependent suppression of motor activity, exploratory behavior (in hole cross and open field tests) and prolongation of thiopental induced sleeping time in mice; maximum effect was shown by chloroform (CFCB) and pet ether (PECB) fractions. In EPM test, chloroform (CFCB) and pet ether (PECB) fractions with similar doses significantly (p < 0.05) increased exploration to and time spent by the treated mice in EPM open arms in a way similar to that of diazepam while the effect of NBCB and HMCB fractions on entry to and time spent in open arms was not found to be statistically significant. These findings provide in vivo evidence that aerial parts of C. benghalensis in general, and chloroform (CFCB) and pet ether (PECB) soluble fraction has significant sedative and anxiolytic effects. Furthermore, these results may justify the scientific basis for the use of this plant in traditional medicine as a modality for anxiety and related disorders.