Effects of aqueous and ethanol extracts of the stem bark of Zizyphus spina-christi L. on isolated rabbit jejunum

Abstract

Zizyphus spina-christi commonly known as Kurna has often been prescribed by traditional medicine practitioners in Borno State for the control of gastro intestinal disorders. The study focused on investigating the curative potentials of the plant material on gastro intestinal motility. Fresh samples of the stem bark were collected and used for this study. The plant material were air-dried for two weeks and pulverized. Six hundred gram of the powdered plant was placed in a thimble and extracted with 2 liters of 95% ethanol (60-80oC). Also, Six hundred gram of the powdered sample was extracted using 2 liters distilled water. The extract concentrates were subjected to preliminary phytochemical screening and then tested on rabbit jejunum. The stem bark extract of Zizyphus spina-christi demonstrated antagonism to acetylcholine induced contraction of rabbit jejunum. The effect was similar to atropine which is a known intestinal smooth muscle relaxant. The effect of acetylcholine on rabbit jejunum showed a dose dependent depolarization response between 10 ƒÊg/ml-160 ƒÊg/ml. Atropine was able to antagonize the effect of
acetylcholine competitively at 10 ƒÊg/ml. At lower doses of acetylcholine, the stem bark water extract showed more antagonist effect. However, as the doses increased similar antagonism was observed for both extracts. The result obtained therefore justifies the traditional use of the plant in controlling abnormal intestinal motility.

Keywords: Zizyphus spina-christi; Aqueous extract; Ethanol extract; Rabbit jejunum; Intestinal motility