菊苣中酚类化合物的HPLC-ECD指纹图谱及抗氧化活性谱-效关系

HPLC-ECD Fingerprint of Phenolic Compounds in Cichorium intybus L.and Spectrum-effect Relationship of Their Antioxidant Activity

建立不同产地菊苣的高效液相色谱-电化学检测法(High Performance Liquid Chromatography-Electrochemical Detection,HPLC-ECD)指纹图谱,采用DPPH、ABTS+自由基清除能力和铁离子还原能力来评价菊苣的体外抗氧化活性,并应用皮尔逊分析、灰色关联度分析和偏最小二乘法回归分析研究菊苣指纹图谱与抗氧化活性之间的“谱-效”关系,探寻菊苣的抗氧化活性成分。该研究从建立的21批不同产地的菊苣指纹图谱中,指认出13个酚类化学成分。菊苣提取物的最高总酚含量达30.76 mg GAE/g,其峰面积与抗氧化活性的相关系数大于0.92,“谱-效”关系研究表明对抗氧化活性贡献较大的有菊苣酸、单咖啡酰酒石酸、异绿原酸B、异绿原酸A、1,5-二咖啡酰奎宁酸、异绿原酸C,表明其化学成分与抗氧化活性之间具有显著的相关性(P<0.01)。该研究建立的HPLC-ECD的菊苣指纹图谱结合统计分析方法研究“谱-效”,既体现样品化学成分的差异性,又可直接反映样品的抗氧化活性,该方法简单、可靠,为菊苣的质量评价及产品开发提供参考。

High performance liquid chromatography-electrochemical detection(HPLC-ECD)fingerprints of Cichorium intybus L.(chicory)of different origins were established.The antioxidant activities of chicory were evaluated in vitro by 1,1-diphenyl-2-picrylhydrazyl(DPPH),[2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)](ABTS+)radical scavenging assays and ferric reducing antioxidant power(FRAP)assays.The"spectrum-effect"relationship between the fingerprint and antioxidant activities of chicory was analyzed using Pearson correlation analysis,partial least squares regression(PLSR)analysis,and gray correlation analysis(GRA)to identify the active antioxidant compounds.In total,13 phenolic compounds were identified from the fingerprint of 21 batches of chicory from different regions.The total phenol content of chicory extract was up to 30.76 mg GAE/g,and the correlation coefficient between peak areas and antioxidant activity was>0.92.According to"spectrum-effect"relationship analyses,chicoric acid,caftaric acid,isochlorogenic acid B,isochlorogenic acid A,1,5-dicaffeoylquinic acid,and isochlorogenic acid C comprised the components primarily contributing to the antioxidant activity of chicory,indicating significant correlations between these chemical compounds and antioxidant activity(P<0.01).The HPLC-ECD fingerprint of chicory established in this study combined with the statistical analysis method exploring the"spectrum-effect"not only indicate the differences in chemical compounds between samples but also directly demonstrate the antioxidant activity of samples.This method is simple and reliable,providing a reference for improving the quality evaluation and product development of chicory.