Nitric oxide scavenging ability of ethyl acetate fraction of methanolic leaf extracts of Chromolaena odorata (Linn.)

Abstract

The nitric oxide (NO. ) scavenging activities of Chromolaena odorata (Linn) King and Robinson, was 
investigated and compared with standard Plant Phenolic antioxidant Quercetin. Disodium 
pentacyanonitrosyl ferrate (2- ) dihydrate (sodium nitroprusside) was used as a nitric oxide donor. On 
disintegration at a physiological pH (7.2), 5 mmol/l of sodium nitroprusside generated a time dependent 
nitric oxide concentration which was scavenged in vitro by the extract. Inhibition of nitrite formation by 
Ethyl Acetate Fraction of Methanolic Extract of C. odorata (EAFCO), showed a dose-dependent 
response. Ability of EAFCO to scavenge nitric oxide radicals in vitro was compared to a standard Plant 
phenolic compound (Quercetin). Quercetin and EAFCO had IC50 = 50 and 380 µg/ml respectively and an 
IC100 of 2000 and 2800 µg/ml respectively. The overall result showed that the plant C. odorata is a good 
nitric oxide radical scavenger. The preliminary phytochemical analysis of chromolaena odorata extracts 
revealed the presence of alkaloids, glycosides, flavonoids, saponins and tannins. Quantitative 
determination of total phenolic content shows that the EAFCO contains an appreciable amount of 
phenolic compounds and may be responsible for the observed potential.