JUSTICIA PEPLOIDES: AN INEVITABLE SOURCE OF NATURAL ANTIOXIDANTS TO RELIEF FROM OXIDATIVE STRESS

Abstract

The rationale of the present investigation was to assess the antioxidant potential of various fractions of Justicia peploides (Nees) T. Anders. To get various fractions, methanolic extract of the plant was dissolved in distilled water and partitioned with n-hexane, chloroform, ethyl acetate and n-butanol sequentially. Phytochemical screening showed presence of phenolics and flavonoids in more amounts in ethyl acetate and n-butanol fraction. The antioxidant potential of all these fractions and remaining aqueous fraction was evaluated by four methods: 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, total antioxidant activity, Ferric reducing antioxidant power (FRAP) assay and ferric thiocyanate assay along with determination of their total phenolics. The results revealed that ethyl acetate soluble fraction exhibited highest percent inhibition of DPPH radical as compared to other fractions. It showed 82.20±1.02% inhibition of DPPH radical at a concentration of 60µg/mL. The IC50 of this fraction was 14.567±1.80µg/mL, relative to butylated hydroxytoluene (BHT, a reference standard), having IC50 of 12.33±0.87µg/mL. It also showed highest total antioxidant activity i.e. 0.92±0.06 (absorbance at 695 nm) as well as highest FRAP value (298.54±1.48 TEµM/mL), highest total phenolic contents (89.9±1.98 GAE mg/g) and highest value of inhibition of lipid peroxidation (55.04±1.46% at concentration of 500 µg/mL) as compared to the other studied fractions. n-butanol fraction also showed good results.