柠檬汁清除DPPH自由基能力及实验方法比较研究

Comparative study on DPPH radical scavenging capacities of lemon juice based on two methods

摘要: 应用电子顺磁共振（EPR）和紫外-可见分光光度计（UV-Vis）两种方法研究美国加州和中国广西柠檬汁清除DPPH自由基的能力。结果表明,EPR方法测得加州和广西柠檬汁的半数清除率EC50值分别为54.53%和32.73%;UV-Vis方法测得加州和广西柠檬汁的EC50值分别为46.41%和30.41%,并且DPPH自由基清除率与柠檬汁浓度呈现良好的正相关性。统计学分析结果表明,两种实验方法的实验结果之间无显著性差异,测试方法对实验结果无显著性影响,两种方法均可用于柠檬汁对DPPH自由基清除能力的研究。

Abstract: The DPPH radical scavenging capacities of California lemon juice and Guangxi lemon juice were determined using electron paramagnetic resonance (EPR) and ultraviolet-visible spectroscopy (UV-Vis) . The EC50 values for California and Guangxi lemon juice measured by EPR method were 54.53% and 32.73%, respectively, and the corresponding vales measured by UV-Vis method were 46.41% and 30.41%, respectively. The study revealed good positive correlation between DPPH radical scavenging rate and lemon juice concentration. In addition, statistical analysis indicated that the results were not significantly influenced by methods. In conclusion, both the two methods could be used for analysis of DPPH radical scavenging capacities of lemon juice.