Abstract:

The antioxidant properties of the melanin extracted from testae of Armeniaca vulgaris var.ansu were investigated with various methods: β-carotene-linoleate model system, scavenging of radicals such as hydroxyl radical (·OH), superoxide anion (O ^-· ₂) and 2, 2-diphenyl-1-picrylhydrazyl (DPPH·). The reducing power and the total phenolic content of the melanin also were determined. The melanin strongly inhibited β-carotene oxidation and exhibited dose-dependent free-radical-scavenging activities against hydroxyl radicals, superoxide anions and DPPH radicals. The melanin was also found to have excellent reducing power. The reducing power of the melanin was higher than that of ascorbic acid (VC) and butylated hydroxytoluene (BHT) at 100～500 μg·Ml^-1 indicating that the melanin from testae of A.vulgaris var.ansu had a strong electron-donating capacity. These antioxidant properties of the melanin opened up a vast range of prospects for making use in many fields, especially in functional food industry and pharmacy.

Key words: melanin, Armeniaca vulgaris var. ansu, antioxidant activity, reducing power, free radical