Evaluation of Anti-diarrheal Activity of 80% methanol crude extract and solvent fractions of the Root of Verbasicum sinaiticum Benth.(Scrophularaceae) in mice.

Abstract

Background: Globally, diarrhea is the second major cause of death (after pneumonia) especially during infancy. The root of V. sinaiticum is traditionally used for the management of diarrhea and dysentery in different parts of the world, including Ethiopia. However, the anti-diarrheal activity of the roots of this plant has not been scientifically verified. Thus, this study was aimed at evaluating the anti-diarrheal activity of 80% methanol crude extract and solvent fractions of the root of V. sinaiticum in mice. Methods: The 80% methanol extract was prepared by maceration and the fractions were obtained by successive fractionation of the crude extract with solvents of increasing polarity (chloroform and ethyl acetate) then distilled water. Castor oil-induced diarrhea, enteropooling, and gastrointestinal motility models were used to evaluate anti-diarrheal activity. Five groups of mice (six animals per group) were used for each model. The negative controls received vehicle (10 ml/kg), whereas the test groups received doses (100,200 and 400 mg/kg) and the positive controls received Loperamide (3 mg/kg) or atropine (1 mg/kg). Data were analyzed using oneway-ANOVA followed by tukey՚s post-hoc and the results were expressed as mean ± standard error of the mean Result: In the castor oil-induced diarrhea model, the crude extract of the plant significantly delayed the onset of diarrhea at 200 (p<0.01), and 400 mg/kg (p<0.001) doses compared to the negative control. It also significantly reduced (p < 0.001) the weight of wet stool at all the serial doses in a similar comparison. In the enteropooling test, the crude extract demonstrated a significant reduction in the weight of intestinal contents at all tested doses as compared with the negative control (p<0.05). The crud extract and all the three fractions significantly inhibited the gastrointestinal motility of charcoal meal at all tested doses (p<0.001) as compared to the negative control. Conclusion: The root of V. sinaiticum has shown promising anti-diarrheal activity which confirms its traditional use. More research is needed and possibly the plant may serve as a potential source of a new agent in the therapeutic armamentarium of diarrhea