In vitro evaluation on the antioxidant capacity of triethylchebulate, an aglycone from Terminalia chebula Retz fruit

Objectives: To evaluate the antioxidant and free-radical scavenging activities of triethylchebulate (TCL), an aglycone isolated from the fruit of Terminalia chebula Retz.
Materials and Methods: Microsomes, mitochondria and red blood cells (RBCs) were isolated from rat liver. The antioxidant capacities were evaluated by determining the inhibitory effects of TCL on lipid peroxidation, hydrogen peroxide (H ₂ O ₂ )-induced RBCs hemolysis and RBCs autoxidative hemolysis. The free-radical scavenging activities were evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) method and 2´,7´-dichlorodihydrofluorescin diacetate (DCFH ₂ -DA) assay.
Result: TCL significantly inhibited FeSO ₄ /Cys-induced microsomes lipid peroxidation and protected both H ₂ O _2- -induced RBCs hemolysis and RBCs auto-hemolysis in a dose-dependent manner. Furthermore, TCL demonstrated potent DPPH free-radical scavenging ability with IC ₅₀ at 2.4×10 ^-5 M. In addition, TCL also moderately suppressed azide-induced mitochondria ROS formation.
Conclusion: These results demonstrated that TCL was a strong antioxidant and free-radical scavenger, which might contribute to the anti-oxidative ability of Terminalia chebula Retz.