Comparative Free Radical Scavenging and Analgesic Activity of Ethanolic Leaves and Stem Extracts of Solanum nigrum

In the present investigation a comparative analysis of the Free radical scavenging potential and analgesic activity of the Ethanolic Leaf (ELS) and stem extracts (ESS) of Solanum nigrum was performed. The extracts were evaluated for its DPPH and hydroxyl free radicals scavenging effect and inhibitory potential on protein carbonyl formation. Total phenolic and flavonoid content of the extracts were also determined by a colorimetric method. The ethanolic extracts of Solanum nigrum were evaluated for its peripheral analgesic activity by Acetic-acid induced writhing response and central analgesic activity by Tail flicking method and Hot plate method in mice. Both the plant extracts scavenged the free radicals in a dose dependent manner. However the scavenging effect was more pronounced in ELS extract when comparable to ESS extract. Both the extract possessed considerable quantity of phenols and flavonoids. In Tail flicking and Hot plate methods the ELS extract of Solanum nigrum showed higher mean basal latency time when comparable to ESS extract suggesting its central analgesic activity. Similarly in Acetic acid induced writhing response the ELS extract exhibited a significant inhibition of writhing 53.28% when comparable to ESS which exhibited an inhibition of 46.53%. The positive control Diclofenac sodium showed 70.66% of writhing inhibition. The analgesic activity of the plants extracts is probably due to its free radical scavenging activity.