Antidiarrhoeal potentials of methanol bark extract of Hymenocardia Acida Tul (Euphorbiaceae) in laboratory animals

Abstract Background The plant Hymenocardia acida (Euphorbiaceae) is utilized as herbal preparation against diarrhoea, dysentery and other diseases. We aimed to determine the antidiarrhoeal potentials of Hymenocardia acida (MEHA) stem bark in vivo and in vitro. Preliminary phytochemical contents, as well as the acute toxicity effect of the extract, were investigated based on standard experimental methods. The antidiarrhoeal properties of the MEHA at 150, 300 and 600 mg/kg were studied against diarrhoea induced by castor oil, intestinal fluid accumulation, as well as intestinal movement tests using distilled water (10 ml/kg) and loperamide/atropine sulphate as the control groups. Besides, the in vitro effects of the extract (8 × 10−2–640 × 10−2 mg/ml) on the rabbit jejunum and guinea-pig ileum were evaluated. Results Phytochemical screening showed alkaloids, glycoside, saponins, tannins, triterpenes, flavonoids and steroids in the MEHA. The median lethal dose (LD50) of the MEHA after oral administration was approximately greater than 2000 mg/kg. The MEHA declined the diarrhoea onset and remarkably decreased the number of watery stools in the group that received 300 and 600 mg/kg. It also elicited a remarkable and non-dose-dependent reduction in the intestinal fluid volume. At 1000 mg/kg, the MEHA significantly inhibited the charcoal movement. In addition, the MEHA (8 × 10−2–640 × 10−2 mg/ml) elicited a remarkable decrease in the contractility of the rabbit jejunum over time and relaxed the guinea pig ileum. Besides, it showed concentration-dependent attenuation of the acetylcholine and histamine-induced contraction. Conclusion The extract under investigation revealed promising antidiarrhoeal properties that justified its traditional claim for use against diarrhoea.