5种不同纯度藻蓝蛋白的抗氧化特性

Antioxidant Properties of Five Phycocyanins with Different Purities

为深入探讨藻蓝蛋白中起抗氧化作用的基团,本实验采用铁离子总还原能力法、2,2’-联氮-双(3-乙基苯并噻唑啉-6-磺酸)(2,2’-azino-bis(3ethylbenzothiazoline-6-sulfonic acid),ABTS)阳离子自由基法、邻苯三酚自氧化法、氧自由基吸收能力法测定5种不同藻蓝蛋白的抗氧化活性并分析其抗氧化活性与蛋白质量浓度、色基含量和藻蓝蛋白纯度的关系。结果表明,在铁离子总还原能力、ABTS阳离子自由基等以电子转移为主的抗氧化体系中,藻蓝蛋白的抗氧化活性与蛋白质量浓度呈正相关,说明在上述两种体系中,藻蓝蛋白中起抗氧化作用的主要基团是蛋白质;在邻苯三酚自氧化的活性氧体系中,藻蓝蛋白的抗氧化活性与蛋白质量浓度呈正相关,与色基含量呈负相关,表明在该体系中,藻蓝蛋白中发挥抗氧化作用的基团是蛋白质;在氧自由基吸收能力基于氢原子转移的抗氧化体系中,藻蓝蛋白的抗氧化活性与色基及纯度呈正相关,说明在该体系中,色基是藻蓝蛋白发挥抗氧化作用的主要基团。

In order to explore the antioxidant functional group in phycocyanin,the antioxidant activities of five different phycocyanins were determined by ferric ion reducing antioxidant power(FRAP),2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)radical cation scavenging,pyrogallol autooxidation and oxygen radical absorbance capacity(ORAC)assays,and their relationship with protein content,chromophore content and phycocyanin purity was analyzed.The results showed that in the FRAP and ABTS radical cation systems,the antioxidant activity of phycocyanins,dominated by electron transfer,was positively correlated with protein content,indicating that the protein components are mainly responsible for the antioxidant effect of phycocyanins.In the pyrogallol autooxidation system,the antioxidant activity of phycocyanins was positively correlated with protein content but negatively correlated with chromophore content,indicating that the antioxidant activity of phycocyanins is attributed to the protein components.In the ORAC system,the antioxidant activity of phycocyanins was positively correlated with chromophore content and phycocyanin purity,indicating that the chromophore plays a principal role in the antioxidant effect of phycocyanins.