Protective Effect of Sundakai (Solanum torvum) Seed Protein (SP) Against Oxidative Membrane Damage in Human Erythrocytes.

Lipid peroxidation by ROS at the membrane level disturbs the inherit integrity of components activating subsequent alterations in the function. In this study, the protective effect of purified Sundakai (Solanum torvum) seed protein (SP) was tested against oxidative membrane damage in erythrocyte membrane. SP prevented oxidative RBC lysis induced by pro-oxidants; Fe:As (2:20 μmol), periodate (0.4 mM), and t-BOOH (1 mM) up to 86, 81, and 86 %, respectively. Further, SP prevented the Fe:As-induced K(+) leakage up to the tune of 95 %. The inhibition offered by SP on K(+) leakage was comparable to inhibition offered by quinine sulfate, a known K(+) channel blocker. SP dose dependently restored Na(+)K(+) ATPase and Ca(2+)Mg(2+) ATPase activities in erythrocyte membrane. The restoration of ATPase activity by SP was two times more than standard antioxidants BHA and α-tocopherol. Besides, SP at 1.6 μmol restored the membrane proteins over Fe:As induction when analyzed by SDS-PAGE, which was comparable to protection offered by BHA. In conclusion, SP is an effective antioxidant in preventing oxidative membrane damage and associated functions mediated by ROS. As SP is non-toxic, it can be used as an effective bioprotective antioxidant agent to cellular components.