Extraction and Demonstration of Uterotonic Activity from the Root of Steganotaenia Araliacea Hochst

Abstract

Background: The root of Steganotaenia araliacea is used for assisting labour in folk medicine. Recent reports indicate that the root could possess uterotonic substances. 
Objectives: The study aimed to evaluate three methods for the extraction of uterotonic principles from the root of S. araliacea growing in Zambia.
Methods: Roots of the plant were collected from Chongwe District of Zambia. The air-dried roots were size-reduced, and the powdered material extracted with hot ethanol, hot distilled water, and cold distilled water. The solvent extracts were concentrated and dried at 110 0C. Solutions of the hot aqueous and cold aqueous extracts were prepared in distilled water and used for organ bath experiments to demonstrate uterotonic activities using strips of pregnant rat uterus. The frequencies and amplitude of contractile forces were recorded. The amplitudes were plotted against log concentration of extract with GraphPad Prism software, and the EC50 values determined.
Results: The percentage yields were 31.3 % for the hot aqueous extract, 8.15 % for the ethanolic extract, and 3.27 % for the cold aqueous extract. The cold aqueous extract showed higher potency (EC50 of 0.54 mg/ml) compared to the hot aqueous extract (EC50 of 2.09 mg/ml).
Conclusion: Root extracts of S. araliacea possess demonstrable uterotonic effects. Extraction of the roots for this purpose could benefit from preliminary defatting with organic solvents, followed by successive extraction with hot and cold water.