Antioxidant properties of Lactuca sativa leaf extract involved in the protection of biomolecules

The aim of the present study was to evaluate the radical scavenging, and biomolecule protective property of Lactuca sativa, an important and commonly used leafy vegetable known for its medicinal properties. The hydro-alcohol extract of Lactuca sativa exhibited strong scavenging effect on 2,2-diphenyl-2-picryl hydrazyl (DPPH), superoxide and nitric oxide, protection against DNA and protein damage. IC 50 values of radical scavenging activity were found to be 162.8 μg/mL for super oxide, 492 μg/mL for nitric oxide radical, 558 μg/mL for metal chelating, and 1236.7 μg/mL for hydroxyl radical. DNA and protein oxidation was prevented dose-dependently and the tail length of DNA as observed in COMET assay was decreased by Lactuca sativa treatment. These results suggest that the extract of Lactuca sativa has potent activity against free radicals and oxidative damage to major biomolecules.