Effect of supplementation of purple pigment from anthocyanin-rich corn (Zea mays L.) on blood antioxidant activity and oxidation resistance in sheep

Anthocyanins are pigments found widely in plants. They have been reported to possess antioxidant activity and an enhancing effect on superoxide dismutase (SOD) activity in monogastric animals. Thus, anthocyanins could also affect the status of the antioxidative defense system in ruminants. This study aimed to investigate the effect of the supplementation of purple pigment from anthocyanin-rich corn on blood antioxidant activities and oxidation resistance in sheep. Twelve sheep were used in a crossover design with two dietary treatments: a diet with purple corn pigment (pigment treatment) and one without (control). The pigment was added to the diets at an anthocyanin concentration of 0.5%. Blood and urine samples were collected to determine the markers of oxidative status. A portion of the plasma was used for an oxidation resistance test, in which plasma was incubated with an oxidizer at 37 °C for 0, 4 and 8 h, and then the degree of oxidation was measured. The pigment addition to the diet caused a significant increase in the SOD activity of the plasma, although the total antioxidant capacity and glutathione concentration in the plasma of both treatment groups were similar. In the oxidation resistance test, the oxidation in the plasma from the pigment treatment group was significantly suppressed compared to that in the control group at 4 and 8 h after the onset of the incubation. These findings indicate that the intake of purple pigment from anthocyanin-rich corn increases the SOD activity and the potential of the antioxidant activity of plasma in sheep.