Comparative evaluation of different cultivars of Flos Chrysanthemi by an anti-inflammatory-based NF-κB reporter gene assay coupled to UPLC-Q/TOF MS with PCA and ANN

Ethnopharmacological relevance: Flos Chrysanthemi (FC), a commonly used traditional Chinese medicine, has five major cultivars ("Boju", "Chuju", "Gongju", "Hangbaiju" and "Huaiju") from different sources. However, the active constituents of these cultivars have not been studied or characterized with respect to their bioactivity, which is a serious problem when considering quality and safety.

Aim of the study: To evaluate the differences among the five cultivars of FC, and to establish a method for the standardization and quality control of FC related to its bioactivity.

Materials and methods: In this study, the different ingredients in five cultivars of FC were identified by UPLC-Q/TOF and PCA, and the anti-inflammatory ingredients of FC were predicted and screened by artificial neural network (ANN) and an NF-κB luciferase reporter gene assay system. Using this comprehensive method, we successfully screened the anti-inflammatory markers of different cultivars of FC.

Results: Nineteen marker ingredients were confirmed to contribute strongly to the cluster, and eleven compounds in the five cultivars of FC were found to exert potential anti-inflammatory effects. Among these compounds, the NF-κB inhibitor activity of apigenin-7-O-6″-malonyl-glucoside, luteolin-7-O-rutinoside, quercetin-7-O-galactoside, quercetin-3-O-glucoside, apigenin-7-O-rutinoside and apigenin-7-O-glucoside were first reported here. Chlorogenic acid, luteolin-7-O-glucoside, 3,5-dicaffeoylquinic acid and luteolin were confirmed to be the most important anti-inflammatory marker ingredients useful for the quality control of FC.

Conclusions: The proposed efficient and systematic method is helpful for the standardization and quality control of FC. Moreover, this comprehensive strategy may prove to be a powerful technique for the rapid establishment of quality control procedures related to bioactivity for other herbal samples and foods.