Evaluation of the antidiarrheal activity of 80% methanol extract and solvent fractions of the leaf of Bersama abyssinica fresen (Melianthaceae) in mice

INTRODUCTION: The use of traditional medicinal plants in the management of diarrhea has long been practiced in Ethiopia. B. abyssinica fresen is one of the plants traditionally used to treat diarrhea whereas an in vivo study had not yet been conducted. Thus, this study aimed to evaluate the antidiarrheal activity of crude extract and solvent fractions of the leaf of B. abyssinica in mice. METHODS: Cold maceration within 80% methanol was used to extract the leaf powder and extract of the leaf was fractionated using n-hexane, chloroform, and distilled water. The in vivo antidiarrheal activity of crude extracts and solvent fractions were tested in experimental models of castor oil-induced diarrhea, enteropooling, and antimotility test. Five groups each with 6 mice were used under the three antidiarrheal models. Positive controls were treated with loperamide 3 mg/kg and atropine 5 mg/kg and 2% tween 80 was used in the treatment of negative controls. The extract and solvent fractions were administered at doses of 100, 200, and 400 mg/kg. Time of onset of diarrhea, number and weight of total and wet feces, the percent reduction in the number of wet feces, weight and volume of intestinal contents, and percent inhibition of intestinal motility were recorded. Data were analyzed using SPSS version 20. RESULT: Defecation of castor oil-induced diarrheal or loose stools was inhibited (p < 0.01 to p < 0.001) at 200 mg/kg and 400 mg/kg of crude extract and aqueous fraction. The crude extract and the aqueous fraction at three doses (p < 0.01 to p < 0.001), the chloroform fraction at 200 mg/kg and 400 mg/kg (p < 0.01 to p < 0.001), and the n-hexane fraction at 400 mg/kg (p < 0.05) reduced intraluminal fluid accumulation compared with the negative control. Castor oil-induced intestinal motility was significantly suppressed with the three-doses of aqueous fraction (p < 0.05 to p < 0.001), 200 mg/kg and 400 mg/kg of crude extract (p < 0.05 to p < 0.01), 400 mg/kg of chloroform and n-hexane (p < 0.01 to p < 0.001) compared with negative control. CONCLUSION: The crude extract, aqueous, and chloroform fractions of B. abyyssinica leaves have promising anti-diarrheal effects, supporting the plant's traditional use to treat diarrhea.