ANTIOXIDANT POTENTIAL FRACTIONATION FROM METHANOL EXTRACT OF AERIAL PARTS OF RUELLIA PROSTRATA POIR (ACANTHACEAE)

Aerial parts of Ruellia prostrata were subjected to extraction and further fractionation to obtain antioxidant rich fraction. Different concentrations of methanolic extract and its n-butanolic fraction were subjected to antioxidant assay by DPPH method, Nitric oxide scavenging activity and reducing power assay. The fractions showed dose dependent free radical scavenging property in all the models. IC₅₀ values for methanolic extract and its n-butanolic fraction were found to be 137.89±5.74 and 42.25±3.17 respectively in comparison to L-Ascorbic acid and Rutin as standard with IC₅₀ values of 6.537±0.235 and 5.437±0.206 respectively, in DPPH model. In nitric oxide scavenging activity the IC₅₀ values were found to be 152.22±6.37 and 67.70±2.29, 21.06±0.953 and 29.93±0.324 for methanolic extract and its n-butanolic fraction, L-Ascorbic acid and Rutin respectively. The fractions showed good reducing power with increasing concentration. However, the n-butanolic fraction showed a good reducing power and better free radical scavenging activity as compared to methanolic extract thus its antioxidant potential is comparable to standards. The phytochemical screenings confirm the presence of triterpenoids glycosides and carbohydrates which are responsible for the antioxidant activity. This is the first report on antioxidant activity of R.  prostrata.