Laxative activity of aqueous root extract of <i>Cnestis ferruginea</i> (VAHL EX DC) in loperamide-induced constipated rats

Abstract

Background and Objective: The age long folkloric claim of Cnestis ferruginea root in the treatment of constipation has prompted investigation into its efficacy. Therefore, this study aims at evaluating the laxative activity of aqueous root extract of Cnestis ferruginea in loperamide-induced constipated rats.
Methods: Thirty (30) albino rats of both sexes weighing 150.30±3.52 g were completely randomized into six groups (A-F) comprising 5 animals each. Animals in group A (control) were administered 1 ml of distilled water while the constipated animals (induced by oral administration of 3 mg/kg body weight loperamide prepared in 0.9% sodium chloride) in groups B, C, D and E were administered distilled water, 25, 50 and 100 mg/kg body weight of the aqueous root extract of C. ferruginea respectively, once daily for 7 days. Constipated animals in group F were administered the reference laxative drug, bisacodyl (25 mg/kg body weight). The feeding characteristics, body weight, fecal properties and gastrointestinal transit ratio were computed at the end of the experimental period.
Results: Preliminary phytochemical screening of the extract revealed the presence of alkaloids, tannins, saponins, flavonoids and anthraquinones while phlobatannins, phenolics, steroids, terpenoids and cardiac glycosides
were not detected. The loperamide significantly (p<0.05) reduced the feed and water intake, number, water content, and weight of the fecal pellets. The feed consumed, water intake and weight of the animals were not significantly (p>0.05) altered in the extract treated animals whereas the number, water contents and weight of the fecal pellets as well as the computed gastrointestinal transit ratio (GIT) increased significantly when compared with the constipated distilled water administered rats. The patterns of changes in the parameters were similar to those obtained with the bisacodyl administered rats.
Conclusion: Available evidence in the present study indicates that aqueous root extract of C. ferruginea possesses laxative activity at the various doses investigated with the best efficacy at 100 mg/kg body weight. This further supports the acclaimed use of Cnestis ferruginea as a laxative.

Keywords: Cnestis ferruginea, Connaraceae, constipation, laxative.