抗氧化活性藻蓝色素与牛血清白蛋白的相互作用

目的: 进一步验证藻蓝色素(phycocyanobilin,PCB)的抗氧化作用,并研究藻蓝色素与牛血清白蛋白(bovine serum albumin,BSA)之间的相互结合反应。 方法: 通过1,1-二苯基-2-苦基肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)清除法验证PCB的抗氧化作用。用荧光光谱法、分光光度法研究了PCB与BSA的相互结合反应。 结果: PCB对DPPH自由基的清除作用呈现一定的量效关系。随着PCB浓度的增加,BSA的荧光强度有规律地降低且呈良好的线性关系。 结论: 抗氧化活性PCB能够有效地淬灭BSA的内源荧光,该猝灭作用属于静态荧光猝灭作用,反应的结合常数K=1.22×10⁶ L· mol^-1,结合位点数n=1.14,与PCB的结合基本不会引起BSA的构象变化。

Objective: To confirm the antioxidant activity of phycocyanobilin(PCB) and study the interaction between PCB and bovine serum albumin(BSA) in aqueous solution. Methods: The antioxidant of PCB was evaluated with DPPH method.And the interaction between PCB and BSA was measured by fluorescence and UV-Vis absorption spectrometries. Results: DPPH radicals scavenging activity of PCB related to its concentration. The fluorescence intensity of BSA decreased with the increasing of the concentration of PCB regularly,which had favorable linear relationship. Conclusion: PCB,with antioxidant activity,could effectively quench the fluorescence intensity of BSA through a single static quenching process.The binding constant K was 1.22×10⁶ L·mol^-1.The number of binding sites n was 1.14.Generally,the interaction with PCB did not change the conformation of BSA.