Anti-inflammatory and free radical scavenging activity of Ricinus communis root extract

Anti-inflammatory and free radical scavenging activities of the methanolic extract of Ricinus communis (RCM) (Euphorbiaceae) Linn. root was studied in Wistar albino rats. The methanolic extract at doses 250 and 500 mg/kg p.o. exhibited significant (P<0.001) anti-inflammatory activity in carrageenan-induced hind paw edema model. The extract at the dose of 500 mg/kg p.o. also exhibited significant (P<0.001) anti-inflammatory activity in cotton pellet granuloma model. The methanolic extract showed significant free radical scavenging activity by inhibiting lipid peroxidation initiated by carbon tetrachloride and ferrous sulphate in rat liver and kidney homogenates. The extract enhanced free radical scavenging activity of stable radical 2,2-diphenyl-1-picryl-hydrazyl (DPPH*), nitric oxide and hydroxyl radical in in vitro assay methods. The results of the study indicate that the methanolic extract of Ricinus communis root possess significant anti-inflammatory activity in acute and chronic inflammatory models in rats. The observed pharmacological activity may be due to the presence of phytochemicals like flavonoids, alkaloids and tannins present in the plant extract with various biological activities.