Evaluation of ethanol and aqueous extracts of cinnamomum verum leaf galls for potential antioxidant and analgesic activity
1Dr. S. G. Reddy College, Bangalore-560 071, India 2Kerala Forest Research Institution-Sub Centre, Nilambur-679 329, India
D R Chandra Kerala Forest Research Institution-Sub Centre, Nilambur-679 329 India E-mail: [email protected]
In the present study, ethanol and aqueous extracts of leaf galls of Cinnamomum verum were prepared to evaluate the antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl free radical scavenging assay and superoxide radical scavenging assay with ascorbic acid as a standard, and analgesic activity by tail immersion test and acetic acid-induced writhing test methods using diclofenac sodium as the reference drug. Swiss albino mice maintained under standard laboratory conditions were used for analgesic tests. In the 2,2-diphenyl-1-picrylhydrazyl assay it was found that the aqueous and the ethanol extract possessed almost equal capacity to inhibit free radicals (IC 50 =13.3 and 13.53 µg/ml) but found less than ascorbic acid (IC 50 =9.96 µg/ml). And in superoxide assay the ethanol extract was found to be more potent in scavenging super oxide radicals when compared to ascorbic acid and the aqueous extract (IC 50 =237.1 and 197.8 µg/ml) with the IC 50 =119.7 µg/ml. For analgesic activity, ethanol extract showed the maximum time required for response against thermal stimuli (6.75±0.47 s) and maximum % of writhing inhibition (44.57%) when compared to aqueous extract (5.25±0.48 s and 32.61%), whereas diclofenac showed response in 7.25±0.25 s 67.39% inhibition in tail immersion and writhing tests, respectively. These results demonstrate that the ethanol extracts of leaf galls possessed high antioxidant and analgesic activity.