凤头姜醇溶和水溶黄酮的抗氧化作用

比较凤头姜水溶和醇溶黄酮对超氧阴离子自由基、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基、2’-联氨-双-3-乙基苯并噻唑啉-6-磺酸(2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),ABTS)自由基的清除能力和总抗氧化能力(铁离子还原能力法),同时用VC和2,6-二叔丁基对甲酚(butylated hydroxytoluene,BHT)作对照。结果表明:在DPPH自由基清除能力测定中,水溶黄酮的抗氧化效果强于醇溶黄酮和BHT,但弱于VC,水溶和醇溶黄酮的半抑制浓度(half maximal inhibitory concentration,IC_(50))分别为585.75μg/m L和1 013.45μg/m L;在ABTS+·、超氧阴离子自由基清除能力和总抗氧化能力测定中,醇溶黄酮的抗氧化效果均强于水溶黄酮、VC和BHT,醇溶和水溶黄酮对ABTS+·的IC_(50)分别为21.90μg/m L和87.54μg/m L;在超氧阴离子自由基清除能力测定中,水溶和醇溶黄酮的IC_(50)分别为26.56μg/m L和22.29μg/m L;在铁离子还原能力测定中,水溶黄酮和醇溶黄酮的TEAC1 000分别为45.78μg/m L和36.42μg/m L。综合研究发现,凤头姜水溶黄酮和醇溶黄酮在不同抗氧化体系中的抗氧化效果存在差异。

Antioxidant Activity of Water-Soluble and Alcohol-Soluble Flavonoids from Fengtou Ginger Rhizomes

The antioxidant activity, in terms of scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) cation radical (ABTS+·) and superoxide anion radical and total antioxidant capacity (TAC, as measured by the ferric-reducing antioxidant power (FRAP) method) of alcohol-soluble and water-soluble flavonoids from Fengtou ginger rhizomes was determined and compared with that of VC and butylated hydroxytoluene (BHT). The results showed that the DPPH radical scavenging activity of the water-soluble flavonoids was better than that of BHT and the alcohol-soluble flavonoids, but weaker than that of VC, and the half maximal inhibitory concentrations (IC50) of the water-soluble and alcohol-soluble flavonoids were 585.75 and 1 013.45 μg/mL, respectively. In terms of ABTS+· and superoxide anion radical scavenging activity and TAC, the antioxidant effect of the alcohol-soluble flavonoids was better than that of VC, BHT and the water-soluble flavonoids. The IC50 values of the water-soluble and alcohol-soluble flavonoids for scavenging ABTS+· were 87.54 and 21.90 μg/mL, respectively, and the IC50 values for scavenging superoxide anion radical were 26.56 and 22.29 μg/mL, respectively. In the FRAP assay, the Trolox equivalent antioxidant capacity (TEAC1 000) of the water-soluble and alcohol-soluble flavonoids were 45.78 and 36.42 μg/mL, respectively. Overall, the antioxidant capacity of the flavonoids from Fengtou ginger rhizomes had different antioxidant activities in different model systems.