车前子及其炮制品色度值、UPLC指纹图谱及体外抗氧化活性的差异研究

Comparative study on chromaticity value,UPLC fingerprint and antioxidant activity in vitro of Plantaginis Semen and its different processed products

目的分析车前子Plantaginis Semen及其不同炮制品的指纹图谱、色度值及抗氧化活性的差异,探讨其化学成分与抗氧化作用的谱效关系。方法采用分光测色仪测定色度值,采用UPLC法建立车前子及其不同炮制品指纹图谱,采用ABTS法测定抗氧化活性,结合相似度评价、方差分析、主成分分析(principal component analysis,PCA)、层次聚类分析(hierarchical cluster analysis,HCA)、正交偏最小二乘-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)等多元统计方法分析车前子及其炮制品的差异;运用偏最小二乘回归法(partial least squares regression method,PLSR)和灰色关联度分析法(grey relation analysis,GRA)分析车前子及其不同炮制品化学成分与抗氧化活性的谱效关系。结果建立的车前子UPLC指纹图谱标定了19个共有峰,炒车前子和盐车前子标定了27个共有峰,合计标定了34个色谱峰,并对其中13个色谱峰进行了指认。多元统计分析表明,车前子与不同炮制品间存在显著差异,PCA与HCA可将车前子生品与炮制品分为2类,OPLS-DA筛选出10个差异性标志成分。车前子炮制前后的粉末色度值ΔE*>6,可被肉眼识别,但不同炮制品间粉末颜色差异不明显。抗氧化活性结果表明,车前子炮制后抗氧化作用增强,不同炮制品间差异不大。相关性分析表明,共有峰的峰面积值对色度值有一定影响,对b^(*)值的影响较小,对L^(*)值、a^(*)值影响较大;PLSR与GRA分析表明,有11个共有峰表征的化学成分与车前子及其炮制品的抗氧化活性关联较大,其中包括原儿茶酸、木通苯乙醇苷B与野漆树苷。结论建立的UPLC指纹图谱及色度值、抗氧化活性的测定方法,可用于车前子及其不同炮制品的鉴别及质量分析,指纹图谱-体外抗氧化活性的谱效关系研究,可为车前子炮制机制的研究提供参考。

Objective To analyze the difference of fingerprint,chromatic value and antioxidant activity of Cheqianzi(Plantaginis Semen,PS)and its different processed products,and explore the spectrum-effect relationship between the chemical components and antioxidant effects.Method The chromaticity value were determined by spectrophotometer,the fingerprint of PS and its different processed products were established by UPLC,and the antioxidant activity were determined by ABTS method.The similarity evaluation,variance analysis,principal component analysis(PCA),cluster analysis,and orthogonal partial least squares discriminant analysis(OPLS-DA)were used to analyze the difference of PS and its different processed products;and the partial least-square method regression(PLSR)and grey correlation analysis(GRA)method were used to explore the spectrum-effect relationship between the chemical components and the antioxidant of PS and its different processed products.Result The established UPLC fingerprint of PS has calibrated 19 common peaks,while 27 common peaks were calibrated in fried PS(fPS)and salt-processed PS(spPS).A total of 34 chromatographic peaks were calibrated and 13 of them were identified.Multivariate statistical analysis showed that there were obvious differences between PS and its different processed products.PCA and HCA divided the raw and processed products of PS into two categories,and OPLS-DA screened 10 differential marker components.The chromaticity valueΔE*of PS and its different processed products was greater than 6,making it visually distinguishable,but the color difference among different processed products was not obvious.The results of antioxidant activity showed enhanced antioxidant effect of PS after processing,with no significant difference among different processed products.Correlation analysis indicated that the peak area values of common peaks had a certain impact on chromaticity values,with a smaller impact on b^(*)values and a greater impact on L^(*)and a^(*)values.PLSR and GRA analysis showed that the chemical constituents represented by 11 peaks were significantly related to the antioxidant of PS and its different processed products,including protocatechuate,calceorioside B and rhoifolin.Conclusion The UPLC fingerprint established in this study,as well as the determination method of chromaticity value and antioxidant activity,can be used for the identification and quality analysis of PS and its different processed products.The study of the spectrum-effect relationship between fingerprint and antioxidant activity in vitro can provide a reference for the study of the processing mechanism of PS.