Abstract

In this study significant free radical scavenging activity was observed in both the methanol (M.E) and aqueous solvent (A.E) respectively extract, determined by evaluating the inhibition concentration (IC50) in each test. The extract correspondingly displayed free radicals scavenging activity with IC50 value of 311.13μg/mL (M.E) and 441.96μg/mL in 2, 2-diphenyl-1-picrylhydrazyl (DPPH). The nitric oxide model displayed IC50 value of 293.77μg/mL (M.E) and 434.93μg/mL (A.E) while the superoxide ion model showed IC50 value of 281.02 μg/mL (M.E) and 440.14μg/mL (A.E) respectively when compared to standard ascorbic acid. This free radical scavenging activity is generally attributed to the presences of polyphenols in the plant. The presence of phenol, flavonoid and total antioxidant in both the extract justifies the antioxidant potential of the plant which brings about its free radicals scavenging potential. GC-MS analysis showed the presence of 6 different phytochemicals with (Z)-7-Hexadecenyl acetate found to be the compound with maximum peak percentage 51.51% in M.E and β-Cyclocitral with 43.90% in A.E respectively. Thus we conclude that the antioxidant activities may be due to the cumulative effect of the phytochemicals present in the plant which genuinely designate them as free radical scavenger.

Key words: Scoparia dulcis, antioxidant, free radicals, phytochemical, Gas chromatography–mass spectrometry (GC-MS).