Phytochemical and Anticonvulsant Properties of Annona senegalensis Pers. (Annonaceae), Plant Used in Burkina Folk Medicine to Treat Epilepsy and Convulsions

Annona senegalensis Pers. (Annonaceae) is claimed in traditional medicine in Burkina Faso to be useful in the treatment of epilepsy. The present study aimed to investigate the phytochemical and pharmacological properties of the aqueous extracts of its root bark. The phytochemical analysis was performed using standard tests according to the Ciulei method. The acute toxicity was carried out in rats and the effect of aqueous extract on the pilocarpine and picrotoxin induced seizure in mice and rats were investigated by curative and preventive modes. The phytochemical screening showed the presence of alkaloids, terpinoids and saponins in the aqueous extract of Annona senegalensis root bark. The intraperitoneal median lethal dose (LD50) was found to be more than 3000 mg/kg in rats. The curative treatment induced a significant decrease of the intensity of the seizure caused by peritoneal injection of pilocarpine in the treated mice when compared to the negative controls. Time put to inhibit 50 % of the seizures by the plant extract was 16 min at the dose of 150 mg/kg against 14 min for standard diazepam (2 mg/kg). In preventive mode, the plant extract prolonged the latency of convulsions. These results suggest that the root bark of Annona senegalensis may possess anticonvulsant properties in rodents.