Antioxidant and radio-protective activities of lemon grass and star anise extracts

Aqueous extracts of Lemon grass (Cymbopogon citratus) and Star-anise (Illicium verum) were prepared and evaluated for antioxidant activity using various in vitro assay systems. The extracts, even at low concentrations, worked as efficient scavengers of DPPH (IC50 of 72–90 µg/ml), and superoxide radicals (77–87% scavenging). The antioxidant activity coefficient as determined by β-carotene bleaching assay was high (600–800). Both the extracts exhibited high reducing power indicating good antioxidant potential. Lipid peroxidation, monitored as thiobarbituric acid-reactive substance (TBARS) were significantly lower (p<0.05) in irradiated meat containing these extracts. Antioxidant potential of Star anise extract was better than Lemon grass extract. The extracts were able to protect against radiation induced DNA damage in pBR322 plasmid.