Antidiarrhoeal effects of Ocimum gratissimum leaf extract in experimental animals.

The aqueous extract of the leaves of Ocimum gratissimum was screened for antidiarrhoeal effects. The extract inhibited castor oil-induced diarrhoea in rats as judged by a decrease in the number of wet faeces in the extract-treated rats. In addition, the extract inhibited the propulsive movement of intestinal contents. On the isolated ileum of guinea-pig, the extract showed no direct action; however, it reduced the responses of the guinea-pig ileum to acetylcholine, nicotine and histamine. Phytochemical tests revealed the main constituents as tannins, steroids, triterpenoid and carbohydrates. These findings suggested that the aqueous extract of the leaves of O. gratissimum might elicit an antidiarrhoeal effect by inhibiting intestinal motility, partly via muscarinic receptor inhibition.