Studies on the antioxidant activity of ethanol extract and its fractions from Pterygota alata leaves

BackgroundReactive oxygen species (ROS) and free radicals are produced during normal physiologic events in a healthy organism. Under pathological conditions ROS are overproduced resulting oxidative stress. This leads to oxidative modifications of the cellular membranes or intracellular molecules. It is accepted that the intake of antioxidant substances reinforces the defense against ROS.AimsTo evaluate the antioxidant activity of various solvent fractions of leaves extract of the plant Pterygota alata.MethodsCrude ethanol extract (CEE) of P. alata leaves and its various fractions such as n-hexane (HF), chloroform (CF), ethyl acetate (EF), and aqueous (AF) were subjected to assay for antioxidants activity. The in vitro antioxidant property was investigated by employing various established systems such as 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay, ferric reducing power assay, and total antioxidant capacity by the phosphomolybdenum assay. Mice with carbon tetrachloride (CCl4)-induced liver injury were used to assess antioxidant effect in vivo by examining the levels of malondialdehyde and tissue protein, and the activities of most important antioxidant enzyme, superoxide dismutase using standard procedures.ResultsAmong the CEE and various fractions, CF exhibited strong antioxidant ability in vitro. The liver of CCl4-intoxicated animals exhibited a significant (p < 0.001) decrease in the superoxide dismutase level and a significant (p < 0.001) increase in the malondialdehyde level. Mice treated with CF and standard drug silymarin caused these values to return to normal level in CCl4-induced liver damage.ConclusionThe present study provides evidence that CF of CEE of P. alata leaves possesses excellent in vitro and in vivo antioxidant effects, which can be a potential source of natural antioxidants and should be further exploited for its use in clinical medicine.