Phytochemical Screening, Analgesic and Anti-Inflammatory Activity of the Ethanol Extract of the Cnidoscolus Phyllacanthus Leaves

Objective: The present study aimed to investigate the analgesic and anti-inflammatory activity of the Cnidoscolus phyllacanthus (family Euphorbiaceae) ethanolic leaves extract in the laboratory using in vivo methods to justify its traditional use in the above-mentioned pathological conditions. Methods: Phytochemical screening was done to find the presence of various secondary metabolites of the plant. In vivo, analgesic activity was performed employing the acetic acid-induced writhing test and tail immersion test on Swiss albino mice at doses of 50, 100 and 200 mg/kg body weight. An anti-inflammatory activity test was done on Wistar rats at three doses (50, 100 and 200 mg/kg body weight) using a carrageenan-induced paw oedema test. Data were analyzed by one-way analysis of variance (ANOVA), and Dunnett's t-test was used as the significance test. P value was considered as the minimum level of significance. Results: Phytochemical screening revealed the presence of coumarin, flavonoids, monoterpenes, diterpenes and naphthoquinones in the extract. In the acetic acid-induced writhing test, the per cent inhibition of writhing response by the extract was 12.82%, 25.64% and 76.67% at 50, 100 and 200 mg/kg doses, respectively (p < 0.01) and showed an increase in pain threshold in tail immersion method. The extract significantly (p < 0.05 and p < 0.01) inhibited carrageenan-induced inflammatory response in rats in a dose-related manner. Per cent, inhibition in paw oedema was 16.39 %, 29.50 % and 52.45 % at 50, 100 and 200 mg/kg doses, respectively. Conclusion: The results obtained from the tests indicate that the plant might have one or more secondary metabolite(s) having central and peripheral analgesic and anti-inflammatory activity.