ASSESSMENT OF MEMBRANE STABILIZATION, ANTIOXIDANT AND THROMBOLYTIC POTENTIAL OF LUTEIN- AN IN-VITRO STUDY

Lutein; an orange-red colored powder, insoluble in water; is a member of the carotenoid family, a xanthophyll pigment. Lutein was evaluated for its antioxidant property when dissolved in different solvents. Solvents used in the study were chloroform, ethanol, methanol and dimethyl sulfoxide (DMSO). The antioxidant potential of lutein was evaluated by total antioxidant capacity, 2, 2’-diphenyl-1-picrylhydrazyl (DPPH), ferric anion reducing power assay (FRAP), 2,2’-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical scavenging, hydroxyl radical scavenging, superoxide radical scavenging and hydrogen peroxide radical scavenging assays.  It was also assessed for its antihemolytic and thrombolytic potential.  Antioxidant property was compared to that of a standard (gallic acid). The antihemolytic property was assessed by the percentage inhibition of hemolysis in heat induced hemolytic assay and osmotic fragility test. The thrombolytic potential was evaluated by the percentage of clot dissolved by lutein in different solvents. Aspirin and trypsin were used as positive controls for antihemolytic and thrombolytic assays respectively. The results for total antioxidant capacity and FRAP were given in terms of gallic acid equivalents and the others were recorded as percentage radical scavenging activity of lutein. In comparison to gallic acid, the antioxidant property of lutein dissolved in various solvents was not very significant. It however showed antioxidant property in all the solvents and a moderate activity was seen when dissolved in chloroform and methanol compared to the other solvents. It was observed that lutein when dissolved in chloroform has shown to reduce heat induced hemolysis; though no significant difference was observed in hemolysis induced by hypotonic solution when compared to aspirin. The thrombolytic activity of lutein dissolved in ethanol was mild when compared to that of trypsin whereas lutein when dissolved in methanol and DMSO did not exhibit any thrombolytic property.