Investigation of Antioxidant Potential of Methanolic Extract of Swertia chirata Buch. Ham.

Aim: To evaluate the in vitro antioxidant potential and total phenolic contents of the methanolic extract of Swertia chirata.

Place and Duration: Department of Botany, Dr. H. S. Gour University (HSGVV), Sagar, between February 2010 to July 2010.

Methodology: The plant material (aerial part) was subjected to defatting with petroleum ether then successively extracted with methanol. Total phenolic contents of methanolic extract was determined using the Folin-Ciocalteau reagent method while in vitro antioxidant potential was evaluated by using DPPH, hydroxyl radical, nitric oxide radical scavenging as well as ferric reducing power assays.

Results: The total phenolic content in 1 mg of methanolic extract of S. chirata was equivalent to 4.5 µg Catechol. The IC50 value of the DPPH method, hydroxyl radical and nitric oxide radical scavenging activity was 222.74±0.19, 307.93±0.10 and 870.55±0.20 µg/ml respectively. When these IC50 value compared with that of standard drug Butylated hydroxy anisole (BHA) the result obtained was as follows: FRSA-SCM>BHA (p=0.000246); HRSA-SCM<BHA (p=0.000507); NORA-SCM<BHA (p=2.22614). These results showed that the S. chirata methanolic extract exhibited significant free radical DPPH scavenging activity and Hydroxyl radical scavenging activity while it exhibited non-significant Nitric oxide radical scavenging activity. In ferric reducing power various concentrations (100, 250 and 500 µg/ml) of methanolic extract of S. chirata showed absorbance 0.013±0.31, 0.156±0.12 and 0.298±0.14. Phytochemical screening showed the presence of phenolic compounds such as flavonoids and tannins which may be responsible for the activity.

Conclusion: Methanolic extract of Swertia chirata showed significant antioxidant activity which suggest the extract may act as a natural antioxidant agent offering effective protection from free radicals.