Chemical Characteristics Combined with Bioactivity for Comprehensive Evaluation of Tumuxiang Based on HPLC-DAD and Multivariate Statistical Methods

Abstract

Background: The dried roots of Inula helenium L. (IH) and Inula racemosa Hook f. (IR) are used commonly as folk medicine under the name of “tumuxiang (TMX)”. Phenolic acid compounds and their derivatives, as main active constituents in IH and IR, exhibit prominent anti-inflammation effect. Objective: To develop a holistic method based on chemical characteristic and anti-inflammation effect for systematically evaluating the quality of twenty-seven TMX samples (including 18 IH samples and 9 IR samples) from different origins. Methods: HPLC fingerprints data of AL (Aucklandia lappa Decne.) whose dried root was similar with HR was added for classification analysis. The HPLC fingerprints of twenty-seven TMX samples and four AL samples were evaluated using hierarchical clustering analysis (HCA) and principle component analysis (PCA). The spectrum-efficacy model between HPLC fingerprints and anti-inflammatory activities was investigated by principal component regression (PCR) and partial least squares(PLS). Results: All samples were successfully divided into three main clusters and peaks 7, 9, 11, 22, 24 and 26 had a primary contribution to classify these medicinal herbs. The results were in accord with the appraisal results of herbs. The spectrum-efficacy relationship results indicated that citric acid, quinic acid, caffeic acid-β-D-glucopyranoside, chlorogenic acid, caffeic acid, 1,3-O-dicaffeoyl quinic acid, tianshic acid and 3p-Hydroxypterondontic acid had main contribution to anti-inflammatory activities. Conclusion: This comprehensive strategy was successfully used for identification of IH, IR and AL, which provided a reliable and adequate theoretical basis for the bioactivity relevant quality standards and studying the material basis of anti-inflammatory effect of TMX. Abbreviations: IH: Inula helenium L.; IR: Inula racemosa Hook f.; TMX: Tumuxiang; AL: Aucklandia lappa Decne.; HCA: Hierarchical clustering analysis; PCA: Principle component analysis; PCR: Principal component regression; PLS: Partial least squares; TCMs: Traditional Chinese Medicines; ChP 2015: Chinese Pharmacopoeia 2015; WHO: World health organization; FDA: Food and drug administration; HPLC-DAD: High-performance liquid chromatography-diode array detection; GC-MS: Gas chromatography-mass spectroscopy; HPLC-MS: High-performance liquid chromatography-mass spectroscopy; UPLC-MS: Ultra high-performance liquid chromatography-mass spectroscopy; RMSE: Root mean square error; RMSECV: Root mean square error of cross-validation; RRT: Relative retention time; RPA: Relative peak area; RSDs: Relative standard deviations