Antidiarrhoeal activity of aqueous leaf extract of Olea europaea var. sylvestris in albino Wistar rats

Olea europaea var. sylvestris, also named oleaster, is widely used by traditional medicine practitioners in Algeria to treat high blood pressure and diabetes. However, the antidiarrhoeal activity of this plant has not been scientifically evaluated. The main aim of the study deals with an investigation of three topics: the phytochemical screening, the acute toxicity, and antidiarrhoeal activity of the oleaster leaf aqueous extract. Acute oral toxicity study was carried out based on Organization for Economic Cooperation and Development 423 guideline. The extract was orally administered in wistar rats at a single dose of 2000 mg/kg body weight and the animals were observed for mortality, behavioral changes and other abnormal signs. Qualitative analysis of phytochemical constituents was carried out using standard methods developed by Harborne, Trease and Evans. Castor oil-induced diarrhoea tests and gastro intestinal motility assay were evaluated in rats to determine the antidiarrhoeal activity of the extract. In the acute toxicity study, the extract did not induce death or any sign of toxicity in treated rats. The preliminary phytochemical screening of the extract revealed the presence of saponins, flavonoids, and triterpenoids. The oleaster extract at oral doses of 100, 200 and 400 mg/kg body weight showed a significant (P<0.05) antidiarrhoeal activity compared to the control group treated with castor oil induced diarrhoea, enteropooling and gastrointestinal motility assay, after charcoal meal administration. The oleaster leaf aqueous extract has shown a gradual response with increasing dose. The present study indicates that the oleaster leaf aqueous extract is safe with antidiarrhoeal property.