The effect of α-tocopherol, sweet chestnut wood extract and their combination on oxidative stress in vivo and the oxidative stability of meat in broilers.

1. This study examined the effect of α-tocopherol (α-T), sweet chestnut wood extract (SCW) and their combination on oxidative stress in vivo and oxidative stability of meat in broilers given diets rich in PUFA. 2. A total of 60 male broilers were individually caged and divided into 6 groups of 10. The C-PALM group received a diet with 7·5% palm fat and the other 5 groups with 7·5% linseed oil. The linseed oil groups were either un-supplemented (C-LIN) or supplemented with α-T or/and SCW as follows: αT-85 (C-LIN diet + 68 IU vit E as all-rac-α-T/kg), αT-200 (C-LIN diet + 183 IU vit E as all-rac-α-T/kg), SCW (C-LIN diet + 3 g SCW/kg) and αT-SCW (C-LIN diet + 68 IU vit E as all-rac-α-T/kg + 3 g SCW/kg). Different parameters of oxidative stress were measured. 3. Linseed oil induced DNA fragmentation and malondialdehyde (MDA) formation, while α-T reduced both parameters, and SCW reduced the DNA damage. A combination (αT-SCW) also reduced plasma MDA. Larger antioxidant capacity of lipid soluble compounds were recorded in groups αT-85, αT-200 and αT-SCW than in the controls but there were no differences between these groups in antioxidant enzymes and total antioxidant status. A combination (αT-SCW) increased tocopherol concentrations in breast muscle and in comparison to the C-LIN group MDA concentrations were reduced in groups αT-85, αT-200 and αT-SCW. 4. It can be concluded that neither of the α-T concentrations were able to prevent all the negative effects of lipid oxidation in vivo and only high concentrations of α-T improved the stability of meat. With the exception of DNA damage, SCW had no impact on in vivo and in vitro measured markers of oxidative stress but may have a sparing or regenerating effect on α-T.