Antioxidant, Antinociceptive and Anti-inflammatory activities of Rhynchosia minima (L) DC

Background: The object of the study was to investigate the possible antioxidant, antinociceptive and antiinflammatory potential of aerial parts ethanol and aqueous extract of Rhynchosia minima using in vitro and in vivo methods. Materials and Methods: Shade dried, pulverized aerial parts of R. minima was extracted with ethanol and water separately and subjected to qualitative and quantitative phytochemical analysis using standard procedures. The antioxidant potential of the plant extracts was assessed using ABTS, DPPH radical scavenging assay. Antinociceptive activity was assessed by acetic acid induced writhing and hot plate analgesic method. Anti-inflammatory effect was evaluated by using carrageenan-induced acute paw edema model. Results: Qualitative phytochemical analysis indicated the presence of glycosides, alkaloids, phytosterols, tannins, flavonoids and phenolic compounds. Ethanol and aqueous extracts of R. minima potentially scavenge the free radicals in ABTS and DPPH radical scavenging assay methods. The results obtained are comparable with ascorbic acid and rutin. Diclofenac sodium (20 mg /kg p.o.) and codeine (5 mg/kg p.o.) was used as reference standard. The AERM and EERM at 200 and 400 mg/kg p.o. showed significant inhibition of abdominal writhing evoked by acetic acid and also increased the pain threshold towards the thermal source in a dose dependent manner. In carrageenan induced acute rat paw edema the AERM and EERM at a dose of 200 and 400 mg/kg p.o. showed significant (p