www.wjpps.com Vol 4, Issue 3, 2015. 582 Kalpana et al. World Journal of Pharmacy and Pharmaceutical Sciences INVESTIGATION OF ANTIOXIDANT AND ANTI-INFLAMMATORY ACTIVITY OF ROOTS OF RUMEX NEPALENSIS 1 Shankar Raj Devkota, 2 Keshav Raj Paudel, 3 Kushal Sharma, 1 Ananda Baral, 1 Sumit Bahadur Baruwal Chhetri, 1 Pravin Parajuli 1 Umesh Thapa, and 1 *Kalpana Parajuli Baral 1 Department of Pharmaceutical Sciences, School of Health and Allied Sciences, Pokhara University. 2 Department of Oriental Medicine Resources, Mokpo National University, South Korea. 3 Department of Pharmacy, Mokpo National University, South Korea. ABSTRACT Inflammation and oxidative stress is associated with many of the acute and chronic diseases which have been troubling mankind. Rumex nepalensis has been used ethno-medicinally for the alleviations of pain and various inflammatory conditions in the western Nepal. The present study was performed to determine in vitro antioxidant activity and in vivo anti-inflammatory activity of R. nepalensis ethanolic extract. In vitro antioxidant activity was evaluated by 2, 2-diphenyl- picrylhydrazyl (DPPH) assay, nitric oxide (NO) scavenging activity, chelating assay and thio barbituric acid reactive substance (TBARS) assay. Three doses, 50 mg/kg, 100 mg/kg, and 200 mg/kg of R. nepalensis were tested for anti-inflammatory activity in carrageenan induced rat paw edema model. The ethanolic extract of R. nepalensis produced dose dependent inhibition of DPPH radicals with IC 50 value of 15.84 μg/ml, showing almost similar effect with standard drug ascorbic acid (IC 50 : 14.32μg/ml). Likewise, it also scavenges the NO radicals with IC 50 value of 146.4 μg/ml. It also inhibited the lipid- peroxidation mediated by oxidizing agent. Similarly, R. nepalensis can dose dependently chelate the metal induced oxidation or enzyme activation with IC 50 value of 97μg/ml. In carrageenan induced inflammation model, R. nepalensis oral extracts produced dose dependent inhibition of rat paw edema significantly (p< 0.05) compared to the control group and 200 mg/kg dose produced maximum percent inhibition of rat paw edema (60.86%) at 3 WORLD JOURNAL OF PHARMACY AND PHARMACEUTICAL SCIENCES SJIF Impact Factor 2.786 Volume 4, Issue 3, 582-594 Research Article ISSN 2278 – 4357 Article Received on 15 Dec 2014, Revised on 09 Jan 2015, Accepted on 03 Feb 2015 Nov 2014 *Correspondence for Author Kalpana Parajuli Baral Department of Pharmaceutical Sciences, School of Health and Allied Sciences, Pokhara University.