How to screen and evaluate the radical scavenging activity of each compound in the mixture remains a challenging project. In the present study, a sensitive and selective method of offline HPLC coupled with chemical methodology was developed for the evaluation of the radical scavenging activity of each compound in a common vegetable, crowndaisy (Chrysanthemum coronarium L.) seeds alcohol extract (CDAE) without the isolation of monomers. The results of LC–ESI–MS/MS showed that the main components of CDAE were chlorogenic acid (3-CQA) (1693.0 μg/g, dry weight), 1,3-dicaffeoylquinic acid (1,3-DCQA, 1378.5 μg/g), 3,5-DCQA (1027.0 μg/g), and 1,4-DCQA (1031.5 μg/g). The results of scavenging free radical activity analysis showed that, among all components, 1,3-DCQA, 3,5-DCQA, 1,4-DCQA, and 3-CQA were mainly responsible for the radical scavenging activity of the extract. Their scavenging rates for 2,2-diphenyl-1-picrylhydrazyl (DPPH) were 86.72%, 83.50%, 83.50%, and 83.43%, respectively. In the assay of scavenging the reactive oxygen species (ROS), CDAE could effectively decrease ROS in RAW264.7 cells without cell toxicity.

中文翻译：

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离线高效液相色谱-LC-ESI-MS / MS联合测定野菊花种子中的酚类化合物的自由基清除活性和成分鉴定

如何筛选和评估混合物中每种化合物的自由基清除活性仍然是一个具有挑战性的项目。在本研究中，开发了一种灵敏且选择性的离线HPLC方法与化学方法相结合，用于评估常见蔬菜冠菊（Chronsanthemum coronarium）中每种化合物的自由基清除活性。L.）种子乙醇提取物（CDAE），无需分离单体。LC-ESI-MS / MS结果表明，CDAE的主要成分是绿原酸（3-CQA）（1693.0μg/ g，干重），1,3-二咖啡酰奎尼酸（1,3-DCQA，1378.5μg / g），3,5-DCQA（1027.0μg/ g）和1,4-DCQA（1031.5μg/ g）。清除自由基活性的分析结果表明，在所有组分中，1,3-DCQA，3,5-DCQA，1,4-DCQA和3-CQA主要负责提取物的自由基清除活性。它们对2，2-二苯基-1-吡啶并肼基（DPPH）的清除率分别为86.72％，83.50％，83.50％和83.43％。在清除活性氧（ROS）的测定中，CDAE可有效降低RAW264.7细胞中的ROS，而无细胞毒性。