采用不同展开剂对红曲色素进行薄层层析，得到7种红色素、4种黄色素、2种橙色素，共13个色素组份。采用•OH体系、O2˙‐体系和DPPH 体系三种抗氧化模型，分别测定了不同色素组份的抗氧化活性。结果表明，红色色素组份和橙色色素组份在上述3种氧化模型中均表现出较高的抗氧化活性。其中，红色色素组份2的抗氧化效果最好，在40 μg/mL的质量浓度下，对•OH的清除率为32%，比同浓度的Vc高20%；对DPPH的清除率达64％，比同浓度的Vc高41%；对O2˙‐的清除率达到34%。

Seven kinds of red pigments, four kinds of yellow pigments and three kinds of orange pigments were separated from fermented rice by Monascus spp. via thin layer chromatography (TLC). And their antioxidant activities were also evaluated. All the 7 red pigments and 3 orange pigments showed high scavenging effects on •OH, O2˙‐ and DPPH, among which Red Pigment No.2 (RP2) had the highest antioxidative acitvity. The scavenging rates of RP2 (40 μg/mL) on •OH and DPPH were 32% and 64%, respectively, which were 20% and 41% higher respectively than those of Vc with the same concentration. The scavenging rate of this pigment on O2˙‐reached 34%.