【摘要】 酪氨酸在辣根过氧化物酶催化下被H2O2氧化为强荧光物质(产物S),姜黄素对其荧光产生猝灭作用,根据Stern-Volmer方程和荧光寿命法研究了姜黄素对产物S的荧光猝灭为静态猝灭。姜黄素与产物S的形成常数K=9.51×108L/mol(25℃),结合点数n=1.94。探讨了产物S与姜黄素的反应机理,该反应的热力学参数△G=-56.11 kJ.mol-1,△H=57.37 kJ.mol-1,△S=365.9 J.K-1.mol-1,说明该反应是自发进行的吸热过程。更多还原

【Abstract】 Because of catalysis of horseradish peroxidase,tyrosine reacted with H2O2 to form the product S which was a strong fluorescent substance.Curcumin acted as a quencher to the product.The static quenching process was confirmed by the measurement of fluorescence lifetime and on the basis of Stern-Volmer plot.The binding constant,K=9.51×108 L\5mol-1 and the number of binding sites n=1.94,were obtained.The reaction mechanism between product S and curcumin was also studied.The thermodynamic parameters,△H=57.37 kJ\5mol-1,△S=365.9 J\5mol-1\5K-1 and the mean value △G=-56.11 kJ\5mol-1,were estimated.The thermodynamic parameters showed that the reaction was an endothermic and spontaneousvan process.更多还原