Abstract

Herbal preparations of Spathodea campanulata leaves are used in southeastern Nigeria for the treatment of convulsions. A preliminary study of the ethanol leaf extract of S. campanulata has confirmed the anticonvulsant potency of the plant. This study was aimed to isolate the constituent(s) responsible for this claimed activity. The ethanol leaf extract was subjected to bioactivity guided fractionation and isolation of the active compound. Anticonvulsant effect of the isolated compound was performed using pentylenetetrazole (PTZ) and electrically –induced seizures. Activities related to anti-convulsion such as effect on rota rod performance and phenobarbitone induced-sleeping time were investigated. Also the acute toxicity studies, as well as the structural elucidation of the isolated compound were carried out using Nuclear Magnetic Resonance (NMR) and mass spectrometry. Results indicated that the new active compound (SCI) isolated fromS. campanulata exhibited significant (p < 0.05) abolition of seizures induced by PTZ and maximal electro shock (MES) seizures. Acute toxicity studies of SCI estimated an oral and intraperitoneal LD₅₀ of 323.59 and 158 mg/kg respectively. Structural elucidation of SCI provided a glycoside: urs-12-en-27α, 30 di-oic acid 3-0-α-L- rhamnopyranosyl (1→2) α-L- arabinopyranoside.

Key words: Spathodea campanulata, glycoside, anticonvulsant, pentylenetetrazole, electro shock.