Antidiarrheal activity of fractions from aqueous extract of Detarium senegalense
The aim of this study was to evaluate the effect of different fractions of the aqueous crude extract of Detarium senegalense stem bark on castor oil-induced diarrhea. Castor oil-induced diarrhea, gastrointestinal motility and castor oil-induced enteropooling methods were used to evaluate the antidiarrheal effects of the fractions. Castor oil was used to induce diarrhea and the effect of all the fractions (chloroform, ethyl acetate, n-butanol, methanol and residual aqueous) were evaluated at the doses of 200 and 400 mg/kg body weight. The results show that all fractions significantly (p<0.05) decreased the frequency of defecation in rats following the induction of diarrhea with castor oil. Ethyl acetate which produced the highest antidiarrheal activity was further subjected to gastrointestinal motility and castor oil-induced enteropooling tests. In the gastrointestinal motility, two test doses of the extract (200 and 400 mg/kg) were administered orally to two groups of rats (n=5), while the third group of rats (control), were treated with normal saline, and the fourth group were treated with diphenoxylate, a conventional anti-diarrheal drug. In the castor oil-induced enteropooling experiment, normal saline was used for the control animals, while 200 and 400 mg/kg of the extract was administered to groups two and three, respectively and atropine, a standard drug, was administered to rats in group four. The ethyl acetate fraction significantly (p<0.05) decreased the gastro-intestinal motility, as shown by the extent of movement of the charcoal meal in the treated rats. It also significantly inhibited the fluid accumulation within the intestine. These findings suggest that the ethyl acetate fraction possess antidiarrheal effect, which may be due to the presence of some phytochemical constituents (alkaloids, flavonoids and tannins) in the plant, which may either be working alone or in combination with each other. This study has demonstrated that D. senegalense fractions, especially the ethyl acetate fraction, possess antidiarrheal activity thus supporting the use of the plant in the treatment of diarrheal diseases.