Evaluation of Anticonvulsant Activity of 80% Methanolic Root Bark Extract and Solvent Fractions of Pentas schimperiana (A. Rich.) Vatke (Rubiaceae) in Swiss Albino Mice

BACKGROUND: Epilepsy is one of the most common serious neurological disorders, responsible for substantial morbidity and mortality due to limited efficacy and negative properties of antiepileptic drugs. Medicinal plants are believed to be an important source of new chemical substances with potential therapeutic effects. Pentas schimperiana (A. Rich.) Vatke is a medicinal plant used in Ethiopian traditional medicine for the treatment of epilepsy. However, it lacks scientific investigation on its anticonvulsant activity. Therefore, this study was conducted to evaluate the anticonvulsant activity of 80% methanol root bark extract and solvent fractions of Pentas schimperiana (A. Rich.) Vatke in mice. METHODS: Anticonvulsant activity was evaluated by using the pentylenetetrazole and maximal electroshock-induced seizure test. The 80% methanolic root bark extract was subjected to successive fractionation with solvents differing polarity, i.e., chloroform, butanol, and water. The test groups received 100, 200, and 400 mg/kg bodyweight of extract and its solvent fractions. RESULT: The ME400 and BF400 at the higher dose exhibited a significant (p < 0.001) anticonvulsant effect in both the pentylenetetrazole and maximal electroshock-induced seizure test compared with control. However, chloroform fraction only showed a significant (p < 0.001) anticonvulsant effect in the PTZ-induced seizure test, while aqueous fraction had least anticonvulsant activity in both seizure-induced tests. Phytochemical screening of Pentas schimperiana (A. Rich.) Vatke root bark extract revealed the presence of alkaloids, saponins, flavonoids, phenols, steroids, terpenoids, and tannins. CONCLUSION: This study indicated that the plant has anticonvulsant activity and is considered as a potential source to develop a new antiepileptic drug.