Antidiarrheal coumarins from Psydrax schimperianus (A. Rich.) Bridson roots

Psydrax schimperianus (A. Rich.) Bridson. roots are used for the treatment of diarrhea in West Arsi zone, Ethiopia.

This study aimed to investigate the in vivo antidiarrheal activity of crude extract and coumarins isolated from the roots of Psydrax schimperianus to provide a pharmacological basis for its traditional use as an antidiarrheal agent in Ethiopia.

The crude root extract of P. schimperianus was tested in vivo for antidiarrheal efficacy in mice utilizing castor oil-induced diarrhea, gastrointestinal transit time, and enteropooling models at doses of 100, 200, and 400 mg/kg. Phytochemical investigation of the crude root extract led to the isolation of two coumarins, isoscopoletin, and scoparone. Isoscopoletin and scoparone were evaluated for antidiarrheal activity against castor oil-induced diarrhea model at 10 mg/kg and 20 mg/kg doses.

The crude root extract of P. schimperianus, at doses of 100, 200, and 400 mg/kg, inhibited defecation by 37.5%, 46.2%, and 61.2%, respectively. At a dose of 20 mg/kg, scoparone and isoscopoletin reduced defecation by 61.2% and 66.6%, respectively.

The study warrants further investigation of isoscopoletin and scoparone towards development as a novel treatment for diarrheal diseases.