Introduction: LDL oxidation by forming and growth of the fatty plaques on the walls of endothelial is an important event in atherogenesis. Sumac plant are rich in polyphenols and flavonoids compounds, with antioxidant effects that inhibit the LDL oxidation could inhibit atherosclerosis. The aim of this study was to determine the effect of flavonoid components sumac extract by gel filtration chromatography on LDL oxidation induced-CuSo₄.

Methods: In this experimental study, LDL was isolated by ultracentrifugation system and gradient medium. The flavonoid fractions were separated from the sumac extract using Sephadex LH-20 gel filtration technic. The LDL oxidation kinetics in the presence of sumac components flavonoid extract were investigated. The formation of oxidation induced  malondialdehyde were measured by TBARS (thiobarbituric acid) method.

Results: The results showed that the flavonoid content of sumac extract significantly increased Lag time (P <0.001) on LDL oxidation kinetics curves, and the malondialdehyde resulting of the oxidation of LDL, in the presence of the extract significantly reduced.

Conclusion: The findings show that flavonoid content sumac extract has a positive effect on reducing LDL oxidation and they are can be a good candidate for further study as well as an effective factor to remove the consequences of oxidation of LDL, such as atherosclerosis.